F PB98-917006

NTSB/SIR-99/04

NATIONAL

TRANSPORTATION

SAFETY

BOARD

WASHINGTON, D.C. 20594

HIGHWAY SPECIAL INVESTIGATION REPORT

BUS CRASHWORTHINESS ISSUES

7010A
National Transportation Safety Board. 1999. Bus Crashworthiness Issues. Highway Special

Investigation Report NTSB/SIR-99/04. Washington, DC.

Abstract: School bus and motorcoach travel are two of the safest forms of transportation in the United

States. Each year, on average, nine school bus passengers and four motorcoach passengers are fatally injured

in bus crashes, according to National Highway Traffic Safety Administration (NHTSA) and motorcoach

industry statistics. In comparison, NHTSA statistics show that in 1998 over 41,000 people were fatally

injured in highway crashes. Although much has been done to improve the safety of school buses and

motorcoaches over the years, the safe transportation of bus passengers, especially students and senior

citizens, continues to be a national safety priority. Children and seniors are predicted to be the fastest

growing segments of our society, and these groups are the primary users of bus transportation. 

The National Transportation Safety Board initiated this special investigation to determine whether additional

measures should be taken to better protect bus occupants. It examines school bus and motorcoach

crashworthiness issues through the analysis of 6 school bus and 40 bus accidents and through information

gathered at the Safety Board’s August 12, 1998, public hearing. This special investigation addresses the

following crucial safety issues: 

• Effectiveness of current school bus occupant protection systems; 

• Effectiveness of Federal motorcoach bus crashworthiness standards and occupant protection systems;

• Discrepancies among different Federal bus definitions;

• Deficiencies in the National Highway Traffic Safety Administration’s Fatality Analysis Reporting

Systems bus ejection data; and

• Lack of school bus injury data.

As a result of this special investigation, the Safety Board makes recommendations to the U.S. Department of

Transportation, the National Highway Traffic Safety Administration, the National Association of

Governors’ Highway Safety Representatives, and the bus manufacturers.

The National Transportation Safety Board is an independent Federal agency dedicated to promoting

aviation, raiload, highway, marine, pipeline, and hazardous materials safety. Established in 1967, the agency

is mandated by Congress through the Independent Safety Board Act of 1974 to investigate transportation

accidents, study transportation safety issues, and evaluate the safety effectiveness of government agencies

involved in transportation. The Safety Board makes public its actions and decisions through accident

reports, safety studies, special investigation reports, safety recommendations, and statistical reviews.

Recent publications are available in their entirety at <http://www.ntsb.gov>. Other information about

available publications may also be obtained from the Web site or by contacting:

National Transportation Safety Board

Public Inquiries Section, RE-51

490 L’Enfant Plaza, East, S.W.

Washington, D.C. 20594

(800) 877-6799 or (202) 314-6551

Safety Board publications may be purchased, by individual copy or by subscription, from the National

Technical Information Service. To purchase this publication, order report number PB99-917006 from:

National Technical Information Service

5285 Port Royal Road

Springfield, Virginia 22161

(800) 553-6847 or (703) 605-6000
Highway Special Investigation Report

Bus Crashworthiness Issues

NTSB/SIR-99/04

PB99-917006 National Transportation Safety Board

Notation 7010A 490 L’Enfant Plaza, S.W.

Adopted: September 21, 1999 Washington, D.C. 20594

iii Special Investigation Report

Contents

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .v

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

School Bus Occupant Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Motorcoach Occupant Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Public Hearing Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

School Bus Crashworthiness Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Nonsimulated Accidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Flagstaff, Arizona . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Easton, Maryland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Buffalo, Montana . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Simulated Accidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Monticello, Minnesota . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

Holyoke, Colorado . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

Holmdel, New Jersey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

School Bus Occupant Crash Protection Systems . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Current Occupant Crash Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

Alternative School Bus Occupant Protection . . . . . . . . . . . . . . . . . . . . . . . . . . .39

Motorcoach Crashworthiness Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

Active Occupant Crash Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Safety Board-Investigated Accidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Occupant Kinematics in Motorcoach Rollovers. . . . . . . . . . . . . . . . . . . . . . . . .45

Occupant Kinematics in Motorcoach Ejections . . . . . . . . . . . . . . . . . . . . . . . . .46

Seat Belts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Motorcoach Crash Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Seat Belt Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50

Passive Occupant Crash Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Window Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Motorcoach Roof Strength and Window Size . . . . . . . . . . . . . . . . . . . . . . . . . .53

Bus Classification and Data Collection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Bus Definitions in the FMVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Data Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

School Bus Occupant Injury Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63

On-Board Recording Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Contents iv Special Investigation Report

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68

Recommendations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70

Appendixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

A: Public Hearing Agenda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

B: Federal Motor Vehicle Safety Standards for Buses. . . . . . . . . . . . . . . . . . . . . . .74

C: Accident Simulation Assumptions and Limitations . . . . . . . . . . . . . . . . . . . . . .80

D: International Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82

E: History of Restraint Recommendations to the FHWA and NHTSA . . . . . . . . . .90

F: Summaries of Selected Motorcoach Accidents Investigated by 

the Safety Board From 1968 Through 1997 . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144
v Special Investigation Report

Introduction

School bus and motorcoach travel are two of the safest forms of transportation in

the United States. Each year, on average, nine school bus passengers and four motorcoach

passengers are fatally injured in bus crashes, according to National Highway Traffic

Safety Administration (NHTSA) and motorcoach industry statistics. In comparison,

NHTSA statistics show that in 1998 over 41,000 people were fatally injured in highway

crashes. Although much has been done to improve the safety of school buses and

motorcoaches over the years, the safe transportation of bus passengers, especially students

and senior citizens, continues to be a national safety priority. Children and seniors are

predicted to be the fastest growing segments of our society, and these groups are the

primary users of bus transportation. Therefore, the National Transportation Safety Board

initiated this special investigation to determine whether additional measures should be

taken to better protect bus occupants. 

To address crucial safety questions on bus safety, this special investigation

examines school bus and motorcoach crashworthiness issues through the analysis of 6

school bus and 40 bus accidents and through information gathered at the Safety Board’s

August 12, 1998, public hearing. (See appendix A.) This report also evaluates the Federal

Motor Vehicle Safety Standards (FMVSS) that govern the design of school buses and

motorcoaches to determine the effectiveness of these standards and to determine whether

further occupant protection measures are needed. Also included here are the results of

computer simulations performed to evaluate the safety levels afforded by passenger crash

protection systems not currently required for school buses. Further, the report reviews

international perspectives on, and developments in, motorcoach occupant protection.

Finally, the report addresses data collection issues that are hampering effective accident

study. During the Safety Board’s discussion of bus crashworthiness issues, this special

investigation identifies the following safety issues:

• Effectiveness of current school bus occupant protection systems; 

• Effectiveness of Federal motorcoach bus crashworthiness standards and

occupant protection systems;

• Discrepancies among different Federal bus definitions;

• Deficiencies in the National Highway Traffic Safety Administration’s Fatality

Analysis Reporting Systems bus ejection data; and

• Lack of school bus injury data.

As a result of this special investigation, the Safety Board makes recommendations

to the U.S. Department of Transportation, the National Highway Traffic Safety

Administration, the National Association of Governors’ Highway Safety Representatives,

and the bus manufacturers.

1 Special Investigation Report

Background

School Bus Occupant Protection

Current large school bus occupant protection is based on a concept called

compartmentalization:1 the seats are strong, closely spaced together, high backed, well

padded, and designed to absorb energy during a crash. This concept evolved from both

crash testing research and Federal rulemaking by the National Highway Traffic Safety

Administration (NHTSA).

In 1967, Dynamic Science and the University of California at Los Angeles2

conducted three crash tests on prestandard (manufactured before April 1977) large school

buses.3 A variety of dummy types and sizes were used in the tests, as well as a number of

different belts, restraint bars, and air bags. The researchers concluded that the high

seatback (28 inches) was the most important safety feature for large school buses,

followed by the use of lap/shoulder belts, lap belts, or another form of restraint. The

researchers cautioned against the use of lap belts with low seatbacks because of the risk of

head injury. 

In 1974, after the Safety Board investigated a series of school bus accidents,

Congress directed the National Highway Traffic Safety Administration (NHTSA) to

establish or upgrade school bus safety standards in eight areas: emergency exits, interior

occupant protection, floor strength, seating systems, crashworthiness of the body and

frame, vehicle operating systems, windshields and windows, and fuel systems. As a result

of this directive, NHTSA, on April 1, 1977, amended or established new motor vehicle

safety standards for school buses, including FMVSS 222, School Bus Passenger Seating

and Crash Protection. This standard improved the crash protection provided by school

buses through compartmentalization. However, the standard did not require the

installation of seat belts. And, even after the 1977 standards were implemented,

researchers and safety advocates continued to examine and debate the effectiveness of seat

belts in school buses. 

In 1984, Transport Canada4

 conducted three poststandard (manufactured after

April 1977) school bus crash tests. Each vehicle (two small school buses and one large

1 In school buses, compartmentalization is used to protect passengers from crash impacts. This is

accomplished by having the seats closely spaced together, with the seat cushions and high seatbacks covered

in an energy-absorbing material. The entire seat structure is designed to absorb energy and to deform to

dissipate the energy of the crash away from the passenger and into the surrounding compartment. 2 Severy, D.M., Brink, H.M., and Baird, J., School Bus Passenger Protection, Society of Automotive

Engineers, Institute of Transportation and Traffic Engineering, University of California at Los Angeles, 1967.

3 A large school bus is defined as one with a gross vehicle weight of more than 10,000 pounds. Before

1977, large school buses were built to the same FMVSS requirements as multipurpose passenger vehicles. 4 Farr, G.N., School Bus Safety Study—Volume 1, Traffic Safety Standards and Research,

Crashworthiness Section, Transport Canada, Quebec City, Canada, 1985.
Background 2 Special Investigation Report

school bus) was subjected to a frontal barrier crash test at approximately 30 mph. The

purpose of these tests was to determine the effectiveness of compartmentalization versus

seat belts. The results indicated that restrained (lap-belted) dummies experienced higher

head accelerations than their unbelted counterparts. The researchers stated that the

increased head accelerations resulted from the dummies’ heads striking the seatbacks in

front such that efficient energy absorption was not possible. The researchers concluded

that compartmentalization functions as intended during frontal impacts, providing good

protection for occupants seated within the compartment, and that lap belts could

potentially increase occupant injuries.

Thomas Built Buses, Inc., performed crash tests on three small school buses in

1985. Thomas Built concluded from these tests that compartmentalization functions as

designed in both frontal and side impacts. In addition, Thomas Built found little difference

in head and chest injuries between the lap-belted dummies and the unrestrained dummies. 

In 1987, the Safety Board conducted a safety study of large school buses.5

 The

study included 43 serious school bus crashes investigated by the Safety Board, including

frontal impacts, side impacts, and rollovers, many of which were preceded by a collision.

The Safety Board concluded that the deaths and serious injuries to the school bus

occupants were mainly the result of the occupants being in direct line with the crash

forces. The Board also analyzed the beneficial effects lap belts may have had during each

crash and concluded that it was unlikely that restraints would have improved the injury

outcome. Generally, the Safety Board concluded that lap belts probably would not have

affected the total number of deaths in these school bus crashes. Furthermore, the Board

concluded that the then-current compartmentalization worked well to protect school bus

occupants from injuries in all types of crashes. 

Since the 1987 Safety Board study, the debate has increased regarding whether

passenger protection, especially in side impact and rollover accidents, can be improved by

seat belts on school buses. Recently, the most serious school bus accidents have involved

collisions with vehicles of large mass (trucks and trains). In these crashes, some of the

passengers that were killed or seriously injured were not seated near the area of impact.

Additionally, four States (New York, New Jersey, Louisiana, and Florida) have passed

legislation requiring that large school buses be equipped with seat belts. Seat belt

advocates argue that lap belts may provide crashworthiness benefits during a collision,

and that, at a minimum, equipping large school buses with lap belts provides children with

message continuity regarding the safety benefits of seat belts. Conversely, others believe

that, because of compartmentalization, no particular safety benefit would be derived from

seat belts, and furthermore, they are concerned that lap belts may cause additional injuries

to children.

5 For further information, read Crashworthiness of Large Poststandard Schoolbuses, NTSB/SS-87/01,

Washington, DC.
Background 3 Special Investigation Report

Motorcoach Occupant Protection

The occupant protection concerns for motorcoaches are somewhat different than

those for school buses. More than 360 million bus passengers travel 28 billion passenger

miles annually in North America by motorcoach. Most motorcoaches today are equipped

with high-backed passenger seats and have large panoramic windows. Through its

investigations, the Safety Board has found that, because motorcoaches are larger in mass

and have a lower center of gravity than school buses, they often respond quite differently

during collisions. As with school buses, the Board has found that those occupants seated

within the direct line of impact are often the most severely injured. However, unlike

school buses, the Board has found that fatal injuries in motorcoach accidents are often the

result of passenger ejection from the coach. A broader discussion of the history and Safety

Board recommendations regarding motorcoach occupant protection appears later in this

report.

Public Hearing Information

On August 12, 1998, the Safety Board held a public hearing in Las Vegas, Nevada,

on “Bus Crashworthiness and Survivability: International and Domestic Perspectives on

Bus Occupant Protection.” Testimony on occupant protection and applicable regulations

was offered by Government, academic, and industry experts, with witnesses coming from

Canada, Europe, Australia, and across the United States. The purpose of the hearing was

to explore ways to protect occupants in bus crashes, including bus design and

manufacturing regulatory standards, restraints used in other countries, and other types of

injury-reducing mechanisms.

The public hearing provided the Safety Board with important information

concerning the current status of occupant crash protection on buses around the world,

including information about areas where occupant protection can be improved and what

types of protection are suitable for passengers on buses.

In the area of school bus safety, the public hearing illuminated concerns of some

experts about the injury-producing potential of lap belts when used by children involved

in frontal impact collisions. Some witnesses suggested that compartmentalization works

better than lap belts in frontal collisions and that, because side collisions are generally not

as violent as frontal collisions (except for those occupants seated in the area of intrusion),

the issue of seat belts is not critical for side collisions. Results from the 1985 Canadian

testing were reiterated at the public hearing. The testing indicated that injuries may be

increased by the addition of lap belts on the current school bus seat. 

At the public hearing, NHTSA presented its new school transportation research

plan “...to develop the next generation of occupant protection for school bus passengers.”

NHTSA plans to conduct research in three phases: 1) define needed actions; 2) develop

testing procedures that best simulate accidents leading to serious injuries; and 3) test and

validate new occupant protection systems. The Safety Board is encouraged that NHTSA

has completed Phase I and is finalizing its report on that phase. Phase II of the plan has
Background 4 Special Investigation Report

begun with the crash testing of two school buses. One test consisted of a

conventional-body large school bus being crashed at 30 mph into a rigid barrier, and the

other test consisted of a stationary large transit-style (flat nose) school bus being struck in

the side by a 25,000-pound tractor semitrailer traveling at 45 mph. At this time, NHTSA is

developing the information gathered in the crash tests for use in investigating potential

new occupant protection systems for school bus passengers. The Safety Board is

optimistic that this research and more like it will result in occupant protection measures

that provide a safer environment for passengers within school buses. NHTSA anticipates

completing its research in the fall of 2000.

In the area of motorcoach safety, the public hearing produced information

indicating that other countries—the European Union member states and Australia—

already have regulations requiring the installation of passenger restraints on

motorcoaches.6 In the European Union, legislation was passed requiring that all

motorcoaches manufactured after October 1999 have either a lap belt and energyabsorbing seat or a lap/shoulder belt installed at every passenger position. The Australian

restraint regulation was going to be similar to the European Union regulation until a seat

was designed with stronger anchorages that incorporated lap/shoulder belts. A restraint

regulation with lap/shoulder standards is in effect in Australia for all motorcoaches

manufactured since 1994, and, currently, most motorcoaches have the new seat restraint

systems. 

At the conclusion of the public hearing, the majority of those participating

indicated a belief that additional research into bus occupant protection needed to be

conducted. The NHTSA testing is a starting point.

6 The United States and Canada are the only countries that use “yellow school buses” for school

transportation. Other countries use small buses and motorcoaches for student transportation. Thus, little

useful comparative experience was available from other countries regarding school bus transport.
5 Special Investigation Report

School Bus Crashworthiness Issues

Overview

Since August 1996, the National Transportation Safety Board has investigated six

school bus accidents in which passenger fatalities or serious injuries occurred away from

the area of vehicle impact. This represents a departure from the circumstances of the

accidents discussed in the Safety Board’s 1987 Large School Bus Study,7 in which

intrusion caused all but 2 of the 13 fatalities and caused most of the moderate or greater

injuries. In addition, the more recent accidents were unlike the accidents in the 1987 Large

School Bus Study. These accidents involved lateral (side) impacts with vehicles of large

mass, lateral (side) impacts with vehicles of large mass and rollover, and single-vehicle

rollover. The Safety Board still believes that compartmentalization is a very effective

means of protecting passengers in school bus accidents. However, because many of the

passengers injured in the recent accidents were believed to have been thrown out of their

compartments during the accidents and thus were unprotected, the Board believes that

other means of occupant protection should be examined. Therefore, the Safety Board

initiated this special investigation to determine the potential injury mechanisms involved

in the six recent accidents and to evaluate whether currently available occupant protection

systems for school buses might have mitigated injury in accidents involving rollover or

high lateral forces. Table 1 lists these accidents in the order discussed.

The six accidents examined by the Safety Board occurred from 1996 to 1998 (see

table 1). Four of these accidents (Easton, Buffalo, Holmdel, and Monticello) involved side

impacts of a large school bus with another large vehicle of equal or greater weight. The

Holyoke accident involved a rear impact followed by a rollover of the bus. The Flagstaff

accident was a single-vehicle rollover that was not preceded by a collision.

Three of these accidents were simulated by the Safety Board to better understand

the dynamics of the vehicles during the collision sequence and also to simulate the

occupant kinematics of a representative accident (Holyoke, Holmdel, and Monticello).

The Monticello occupant simulation was conducted to determine the possible kinematics

of the occupants during this complicated accident scenario in which multiple impacts

occurred and also to determine the potential injury producing impacts. The Holyoke

simulation was conducted to determine a potential ejection path of the two simulated

7 For further information, read Crashworthiness of Large Poststandard Schoolbuses, NTSB/SS-87/01,

Washington, DC. No information from this study, beyond the current applicable Federal Motor Vehicle

Safety Standards (FMVSS), will be included in this special investigation. No changes have been made to the

passenger protection standards applicable to large school buses since the Safety Board adopted the Large

School Bus Study in 1987. Safety improvements have been made in other areas, including an amendment to

FMVSS 217 requiring additional emergency exits and the addition of a requirement for wheelchair

securements to FMVSS 222. Other changes include modifications to the mirror requirements of FMVSS

111; changes to the body joint strength of FMVSS 221; and the establishment of a new standard, FMVSS

131, requiring stop signal arms. (For more information on FMVSS applicable to school buses,

see appendix B.)
School Bus Crashworthiness Issues 6 Special Investigation Report

occupants seated in the rear of the bus on the driver’s side. The Holmdel simulation was

conducted to determine the possible occupant kinematics during an accident resulting in

serious injury to an occupant on the opposite side from the impact. For all three accidents,

the effectiveness of compartmentalization was investigated, as well as the potential

restraint systems currently available for large school buses.

The remaining three accidents were not simulated for a variety of reasons. The

Flagstaff accident involved an extremely complicated rollover where the sequence of

events was unclear. Because the vehicle dynamics were not fully understood, occupant

kinematics would be difficult to accurately determine, requiring that a number of

assumptions be made and, thereby, limiting the conclusions drawn from such a simulation.

The Easton accident was not simulated because the vehicle and occupant kinematics were

similar to the kinematics of other accidents being simulated. As in the Monticello and the

Holmdel accidents, the school bus in the Easton accident was struck by a large truck. In

addition, an occupant on the opposite side of the bus from the impact was injured, as in the

Holmdel accident. The Buffalo accident involved the collision of a train into the side, rear

portion of a large school bus. Two passengers in the rear of the vehicle, one in the area of

intrusion and one across from the area of intrusion, were fatally injured while the

passengers at the front of the bus, away from the intrusion, sustained only minor or

moderate injuries. Consequently, this accident was not simulated because the impact

experienced by the bus was too severe to have expected any occupant protection system to

reduce the level of injury sustained by the two fatally injured passengers. 

Table 1. School bus accidents analyzed

Accident Date Fatalities Injured Not Injured1

Nonsimulated Accidents2

Flagstaff, Arizona

(WRH-96-F-H014) 08/14/96 0 31 1

Easton, Maryland

(HWY-98-M-H005) 10/31/97 1 25 12

Buffalo, Montana

(HWY-98-M-H022) 03/10/98 2 4 0

Simulated Accidents2

Monticello, Minnesota

(CRH-97-F-H004) 04/10/97 3 11 0

Holyoke, Colorado

(HWY-98-F-H043) 09/01/98 0 11 2

Holmdel, New Jersey

(HWY-98-F-H045) 09/18/98 0 7 0

Total 5-Passengers

1-Driver

85-Passengers

4-Drivers

14-Passengers

1-Driver

1 Includes passengers who may have received minor injuries but were not examined by professional medical personnel.

2 Nonsimulated accidents were analyzed based on reported vehicle dynamics and injury data. Simulated accidents were 

analyzed using a variety of computer programs capable of evaluating specific mechanical and biomechanical issues 

for similar types of accidents. A simulation does not replicate the actual accident.
School Bus Crashworthiness Issues 7 Special Investigation Report

Nonsimulated Accidents

The Flagstaff, Easton, and Buffalo accidents resulted in serious injuries or

fatalities to passengers seated away from the crash impact area but propelled from their

compartments due to the high crash forces experienced during these accidents. These

passengers subsequently struck surfaces not designed to absorb crash energy, such as the

bus’ roof and side walls, sides of seatbacks, or other passengers. Crashworthiness issues

specific to these accidents are summarized below.

Flagstaff, Arizona

In this accident, a 72-passenger school bus rolled over after the driver lost control

of it. Although no fatalities resulted, five passengers were ejected from the bus. (See

figures 1 and 2.) Of the ejected passengers, one was severely injured (AIS-4) 8,9 and four

received minor to moderate injuries (AIS-1 and -2). (See seats 1A, 1F, 8A, 9A, and 10A in

figure 3.) The lap-belted driver received severe injuries (AIS-4). The passengers on the

driver’s side received minor to moderate injuries (AIS-1 and -2). The only serious to

critical injuries (AIS-3 to -5) occurred to passengers seated on the right-hand side of the

bus (seats 1F, 5E, 6F, and 12D), most likely as the result of being propelled out of their

compartments and striking surfaces not designed to absorb impact energy. Because only

one of five ejected passengers was seriously injured and because the injury levels of

passengers located in proximity to each other on the bus differed substantially, it is

difficult to determine whether an occupant restraint system would have mitigated or

prevented injuries.

8 Abbreviated Injury Scale (AIS) refers to the abbreviated injury scale (revised 1990) of the American

Association for the Advancement of Automotive Medicine. The AIS classifies injuries as follows:

AIS-0=No injury; AIS-1=Minor; AIS-2=Moderate; AIS-3=Serious; AIS-4=Severe; AIS-5=Critical;

AIS-6=Unsurvivable; and AIS-9=Unknown.

9 See last page of this document for a list of all acronyms and abbreviations used in this report. 

 Figure 1. Flagstaff school bus postaccident damage
School Bus Crashworthiness Issues 8 Special Investigation Report

 Figure 2. Flagstaff accident scene diagram
School Bus Crashworthiness Issues 9 Special Investigation Report

 Figure 3. Flagstaff bus seating diagram
School Bus Crashworthiness Issues 10 Special Investigation Report

Easton, Maryland

In this accident, a 66-passenger school bus was struck at an intersection by a truck

pulling an empty semitrailer. The truck cab initially struck the left side of the school bus

near the driver’s window, causing the bus to rotate in a clockwise direction. The second

impact occurred when the right-front corner of the semitrailer swung into the rotating bus,

then struck the left side of the school bus near the rear axle. (See figures 4 and 5). 

The lap-belted driver was fatally injured as a result of high crash forces in the

intrusion area. Three of the four passengers seated in row 1 (figure 6), directly behind the

driver, sustained minor injuries. Although these passengers would not have experienced

the same level of intrusion as the driver, they would have experienced similar vehicle

dynamics. The other passenger in row 1, who was furthest from the impact in seat 1F,

experienced serious injuries (AIS-3), most likely sustained from being propelled toward

the impact zone. Three of the four most seriously injured passengers (seats 1F, 7F, and 8E)

were originally seated on the side of the bus opposite the two impact areas and were likely

injured from being propelled from their compartments into the impact area by the high

lateral forces experienced during the accident and from striking surfaces not designed to

absorb crash energy. Passenger restraints may have reduced passenger injuries by

preventing the lateral movement of passengers toward the impact area and by preventing

passengers from striking each other. However, because a properly worn lap belt limits the

motion of the pelvis relative to the upper body, the restrained passenger’s upper body

could have been whipped sideways by lateral crash forces.10 This whipping action may

result in high forces being concentrated on the head, possibly causing serious injury. The

passengers displaced by the initial impact away from the area of secondary impact (seats

8A, 9A, and 9C in figure 6) may have received worse injuries had they been wearing

restraints because of greater exposure to intrusion.

10 Similar kinematics would be experienced by a passenger who slid out of the shoulder portion of a

lap/shoulder belt due to belt orientation and vehicle dynamics.
School Bus Crashworthiness Issues 11 Special Investigation Report

 Figure 4. Easton school bus postaccident damage

 Figure 5. Easton accident scene diagram
School Bus Crashworthiness Issues 12 Special Investigation Report

 Figure 6. Easton bus seating diagram
School Bus Crashworthiness Issues 13 Special Investigation Report

Buffalo, Montana

In this accident, a freight train traveling 45 mph struck a school bus between the

bus’ rear axle and left rear bumper. The impact caused the bus to rotate 180 degrees

counterclockwise, and the bus body to separate from its chassis. (See figures 7 and 8.) The

passenger in seat 7B was fatally injured from the train’s intrusion and resulting crash

forces. (See figure 9.) The other fatally injured passenger (seat 7E) was likely thrown into

the impact zone during the collision and sustained critical head injuries from the impact

forces. Although a restraint system would have reduced the chances of this passenger

being propelled into the impact zone, the restraint may not have prevented injuries

resulting from the high crash forces due to the severe lateral impact. In addition, had the

restraint been a correctly worn lap belt, the passenger’s pelvis motion would have been

limited relative to the seat, causing his upper body to be whipped sideways, potentially

resulting in head injuries similar to those actually received in the accident.11 The driver

and other passengers, who were seated at the front of the bus, did not receive serious

injuries.

11 This may also occur with a lap/shoulder belt, depending upon belt orientation.

 Figure 7. Buffalo school bus postaccident damage
School Bus Crashworthiness Issues 14 Special Investigation Report

 Figure 8. Buffalo accident scene diagram
School Bus Crashworthiness Issues 15 Special Investigation Report

Simulated Accidents

Methodology

Each simulated accident was evaluated twice: first, to determine the dynamics of

the vehicles involved in the collision and second, to evaluate possible occupant kinematics

using vehicle dynamic data. Although a simulation does not replicate the actual accident,

it is designed to evaluate specific mechanical and biomechanical issues for similar types

of accidents.

Five programs were used to simulate the vehicle dynamics. The software

programs were:

 Figure 9. Buffalo bus seating diagram
School Bus Crashworthiness Issues 16 Special Investigation Report

• McHenry Simulation Model of Automobile Collisions (m-smac),12 a twodimensional analysis of multiple vehicle collisions calculating vehicle

deformations and trajectories;

• Engineering Dynamics Corporation Vehicle Simulation Model (EDVSM),13 a

three-dimensional analysis of a single vehicle’s response to the driver’s inputs,

such as steering, throttle, brakes, and gear selection;

• Engineering Dynamics Corporation Vehicle Dynamics Simulator (EDVDS),14 a

three-dimensional simulation of a commercial vehicle’s dynamic response to

driver inputs and road conditions that can incorporate a tow vehicle and up to

three trailers and which is an extended version of the Phase 4 program

developed at the University of Michigan;

• Engineering Dynamics Corporation Simulation of Automobile Collisions,

(EDSMAC4),15 a two-dimensional simulation analysis of vehicle collisions

based on the “smac” model originally developed by Calspan for the National

Highway Traffic Safety Administration (NHTSA) that allows multiple vehicles,

trailers, and/or barriers to be analyzed; and

• Engineering Dynamics Corporation General Analysis Tool (EDGEN),16 a threedimensional kinematics tool with inputs for eight different vehicle positions and

velocities that can calculate the time required to travel between points.

Two programs were used to simulate the occupant kinematics of the

representations of fatally or seriously injured bus occupants in the simulated accidents.

MAthematical DYnamical MOdels (MADYMO)17 is a general purpose software package

that allows users to perform simulations using both rigid and flexible bodies. This

software program enables modeling of an unlimited number of occupants and also

incorporates finite element technology. Graphical Articulated Total Body (GATB),18

developed by Collision Engineering Associates for the Human Vehicle Environment

(HVE) system, is a new version of the Articulated Total Body (ATB)19 program that has

been used to analyze occupant kinematics in motor vehicle collisions for approximately

10 years. The GATB uses the graphics built into the HVE system to further the viewing

12 McHenry Software, Inc., P.O. Box 5694, Cary, North Carolina 27512.

13 Human Vehicle Environment, Engineering Dynamics Corporation, 8625 S.W. Cascade Boulevard,

Suite 200, Beaverton, Oregon 97008-7100. 14 Engineering Dynamics Corporation.

15 Engineering Dynamics Corporation.

16 Engineering Dynamics Corporation.

17 For further information, see MADYMO User’s Manual 3D Version 5.3, TNO Road-Vehicles

Research Institute, November 1997. MADYMO simulations conducted for this special investigation were

performed in conjunction with National Highway Traffic Safety Administration and Information Systems

and Services, Incorporated, a NHTSA contractor.

18 Grimes, W.D., Using ATB Under the HVE Environment, Society of Automotive Engineers Paper No.

970967, 1997. 19 Obergefell, L.A., Gardner, T.R., Kaleps, I., and Fleck, J.T., Articulated Total Body Model Enhancements,

Volume 2: User’s Guide, Report No. AAMRL-TR-88-043, Armstrong Laboratory, Dayton, Ohio.
School Bus Crashworthiness Issues 17 Special Investigation Report

capabilities of the ATB program. The maximum number of occupants that the GATB can

currently simulate is four (when the Monticello accident was simulated, the GATB’s

capabilities were limited to one simulated occupant). The GATB also interfaces with the

software used for the vehicle simulations, enabling enhanced graphics and ease of

implementation.

MADYMO was used to model the Monticello accident, and GATB was used to

model the Holyoke and Holmdel accidents.20 For all three accidents, simulations were

performed on unrestrained simulated occupants and on simulated occupants in lap and

lap/shoulder belts. The belt attachment points were placed on the base of the seat cushion

for the lap belts and on the top of the seatback for the shoulder harness, remaining in that

location regardless of the simulated occupant’s size. The seatback stiffnesses were not

changed for the restrained conditions. The belt attachment points were rigidly fixed

throughout the simulation. Default material properties were used for the seats, windows,

walls, and belts. For the Monticello accident, the belts were constructed with the available

finite elements in MADYMO. For the Holyoke and Holmdel accidents, the belts were

defined based on the default belt stiffness characteristics of the HVE system. For further

information concerning the assumptions and limitations of these simulations, see

appendix C. 

Monticello, Minnesota

On April 10, 1997, at approximately 8:11 a.m., a 1995 International

Navistar/Thomas Built body 77-passenger school bus was traveling westbound on Wright

County Road 39 near the town of Monticello, Minnesota, at a driver-estimated speed of 45

mph. Concurrently, a 1993 Mack tractor with an empty, 4-axle, 29-foot semitrailer was

traveling north on Wright County Road 11 at a witness-estimated speed of 50 to 55 mph.

The bus was occupied by a 24-year-old lap-belted driver and 13 passengers, ages 6 to 11.

A 42-year-old lap/shoulder belt-restrained driver occupied the combination unit. 

According to a witness, both vehicles approached the intersection where the

tractor-semitrailer failed to stop for the posted stop sign, skidded into the intersection, and

was struck by the school bus. At impact, the front of the school bus contacted the right

side of the tractor at the right front wheel with approximately 43 inches of overlap. A

second impact occurred when the right front corner of the semitrailer struck the left side of

the school bus at the roofline, which resulted in a 17.5-inch-deep depression. During the

second impact, the tractor’s tandem wheels deformed the lower part of the side panel of

the school bus. A third impact then occurred, when the semitrailer side-slapped the school

bus, which was rotating clockwise as a result of the first two impacts. (See figures 10

and 11.) 

20 The six passengers in the rear of the bus in the Monticello accident, who ranged from 9 to 11 years

old, were simulated using the 6-year-old P6 modeled dummy and the Hybrid III 6-year-old modeled dummy.

The four passengers in the rear of the bus in the Holyoke accident, who ranged from 8 to 15 years old, were

simulated using simulated occupants of similar height and weight to the actual passengers. The four

passengers in the front of the bus in the Holmdel accident, who ranged from 7 to 16 years old, were

simulated using simulated occupants of similar height and weight to the actual passengers.
School Bus Crashworthiness Issues 18 Special Investigation Report

The truckdriver and three school bus passengers seated in the left rear of the bus

were fatally injured. Additionally, one school bus passenger sustained critical injuries, two

sustained severe injuries, and three sustained serious injuries. The school bus driver and

one passenger sustained moderate injuries, and three passengers sustained minor injuries.

Details of the simulation of this accident are provided below.

Simulated Vehicle Dynamics. The m-smac results indicated that the tractorsemitrailer was traveling approximately 49 mph, and the bus was traveling approximately

50 mph at impact. As discussed above, three separate impacts occurred between the bus

and the tractor-semitrailer: a frontal impact of the bus into the side of the trailer, a side

impact of the semitrailer into the side of the bus, and a side slap of the semitrailer into the

side of the bus.

Three of the passengers in the rear of the bus on the driver’s side were fatally

injured. Results obtained from the simulations revealed significant differences in the crash

pulse and the change in velocity (Delta V) between the center of gravity (CG) of the bus

and points at the rear of the bus, possibly contributing to the severity of the injuries to the

passengers in the rear. These differences are detailed in table 2. The greatest variance

occurred during the last collision when the semitrailer side-slapped the rotating bus. As a

result of this collision, the change in velocity at the rear of the bus, according to the

simulation, was 44 mph versus 12 mph at the bus’ center of gravity. During the same

collision, portions of the bus forward of the center of gravity underwent a smaller change

in velocity than did portions at the center of gravity, correlating again with the severity of

the injuries sustained by passengers in that region of the bus.

 Figure 10. Monticello school bus postaccident damage
School Bus Crashworthiness Issues 19 Special Investigation Report

Simulated Occupant Kinematics. In general, the simulated occupants in the rear

of the bus first went forward in their seats and then contacted the seats in front of them

with their legs, chest, and head. (See figure 12 for a time history of the unrestrained, lap

belt, and lap/shoulder belt simulation conditions.) Due to the bus’ clockwise rotation, the

simulated occupants then slid toward the right side of the bus. Passengers seated on the

right side of the bus quickly contacted the side of the bus and the windows and stayed in

 Figure 11. Monticello accident scene diagram
School Bus Crashworthiness Issues 20 Special Investigation Report

that position until the third impact (side slap) of the bus and semitrailer. Passengers

originally seated on the left side of the bus struck the edges of the adjacent seats and also

hit other simulated occupants during the motion. The clockwise rotation of the bus

continued until the third impact of the bus with the semitrailer. This impact started a

counterclockwise rotation of the bus and, therefore, caused the simulated occupants to

slide back toward the left side of the bus. The passengers originally seated closest to the

left side of the bus impacted the windows and the side of the bus, typically with their

heads or upper torsos. Passengers originally seated further from the left side of the bus

struck other simulated occupants while sliding toward the left, toward the impacting

semitrailer. 

The bus’ rotation caused the opposite motion for simulated occupants in the front

of the bus. Those simulated occupants first went forward in their seat and again contacted

the seat in front. The simulated occupants then slid toward the left side of the bus.

Simulated occupants on the left side of the bus contacted the side of the bus and the

windows quickly, while those on the right collided with those already on the left side of

the bus.

When restrained by a lap belt, the simulated occupant’s pelvis was essentially

fixed to the seat, causing the upper torso to whip sideways. This whipping action, in turn,

caused the simulated occupants seated opposite the impact area (seats 11F and 13F in

figure 13) to pivot about the pelvis and strike their heads and torsos on the seat cushions.

Head injuries were predicted from these impacts. In addition, due to the seats’

configuration and the dynamics of the bus, the simulation predicted hyperextension of the

neck as simulated occupants on both sides of the bus rotated about the seatback.

Simulated occupants wearing lap/shoulder belts displayed similar kinematics as

those restrained by lap belts alone.21 During the final impact, the side slap, the upper torsos

of simulated occupants seated opposite the impact area (seats 11F and 13F) slid out from

their shoulder belts. Previous research22,23 has indicated that the upper torso may slide from

Table 2. Peak velocity changes at various locations 

along the bus in the Monticello accident

Impact Delta V (mph)

Center of Gravity Left Rear Corner

1st 31 34

2nd 18 18

3rd 12 44

21 For all simulated occupants, the shoulder portion of the lap/shoulder belt was anchored in the

outboard positions of the bus seat, with the upper anchorage always mounted on the outside of the seatback.

22 Cesari, D., Quincy, R., and Derrien, Y., Effectiveness of Safety Belts Under Various Directions of

Crashes, Society of Automotive Engineers Paper No. 720973, 1972. 23 Horsch, J., Occupant Dynamics as a Function of Impact Angle and Belt Restraint, Society of

Automotive Engineers Paper No. 801310, 1980.
School Bus Crashworthiness Issues 21 Special Investigation Report

 Figure 12. Monticello simulation time sequence history (various restraint conditions)
School Bus Crashworthiness Issues 22 Special Investigation Report

 Figure 13. Monticello bus seating diagram
School Bus Crashworthiness Issues 23 Special Investigation Report

the restraint during side-impact scenarios. These simulations indicate that a potential for

head injury exists when the torso slides from the upper restraint. The predicted injuries

from the simulation in each of the three restraint conditions and the actual injuries

sustained by the bus passengers are summarized in table 3.

In the unrestrained condition, three simulated occupants were predicted to sustain

head injuries. These simulated occupants represented the fatally injured passengers during

the actual accident (seats 11A, 12A, and 13A). Four simulated occupants wearing lap belts

were predicted to sustain head injuries; five simulated occupants wearing lap/shoulder

belts were predicted to sustain head injuries. During the restrained conditions, simulated

occupants seated on the side of the bus opposite the impact area were predicted to sustain

injuries from the head’s impact onto the seat cushion as the upper body whipped about the

fixed pelvis. 

The simulation predicted chest accelerations for four unrestrained simulated

occupants, four lap-belt restrained simulated occupants, and three lap/shoulder

Table 3. Summary of actual injuries to the Monticello bus occupants and of predicted 

injuries based on various simulation conditions

Predicted Injuries to Simulated Occupants

Seating 

Location

Body

Segment

Actual 

Injuries Unrestrained Lap Belt Lap/Shoulder Belt 

11A

(fatality)

Head

Thorax

Neck

✓

✓

✓

✓

–

✓ ✓

✓

11C Head

Thorax

Neck

✓

–

✓

11F Head

Thorax

Neck

✓

–

✓

✓

✓

12A

(fatality)

Head

Thorax

Neck

✓

✓

✓

✓

✓

–

✓

✓

✓

✓

13A

(fatality)

Head

Thorax

Neck

✓

✓

✓

✓

–

✓

✓

✓

✓

✓

13F Head

Thorax

Neck

✓

–

✓

✓

✓

✓

✓

✓ Predicted injury based upon simulation.

– Data unavailable. Neck injuries were not examined in the unrestrained condition.
School Bus Crashworthiness Issues 24 Special Investigation Report

belt-restrained simulated occupants. Neck injuries24 were predicted for three lap beltrestrained simulated occupants and two lap/shoulder belt-restrained simulated occupants. 

This simulation indicates that caution should be exercised when placing lap belts

or lap/shoulder belts on school buses without altering the configuration of the seats to

restrain the upper body during side impacts. Injuries could potentially result with belt

usage that would not have resulted with compartmentalization alone.

Holyoke, Colorado

On September 1, 1998, approximately 3:45 p.m., a 1986 International

Navistar/Blue Bird body, 54-passenger school bus began to accelerate from a stop in the

eastbound lane of Highway 6, near Holyoke, Colorado, when it was struck in the rear, on

the left side, by the right front of a 1992 Peterbilt tractor pulling an empty semitrailer. The

bus was occupied by a 42-year-old lap-belted driver and 12 passengers, ages 7 to 15. The

bus rotated 180 degrees clockwise then overturned onto its left side. A 15- and an 8-yearold bus passenger were ejected from the rear of the bus.25

The semitrailer struck the rear left side of the of the school bus. The bus was

traveling approximately 5 mph at the time of the impact, after reportedly letting one

passenger off the bus at a bus stop; the tractor was traveling approximately 50 mph. At

impact, the front of the bus accelerated forward and then began to rotate clockwise while

the tractor-semitrailer decelerated rapidly and continued to swerve to the left. As the bus

continued to rotate, the left rear bus tire dug into the pavement, creating a deep gouge.

After rotating approximately 180 degrees in a clockwise direction, as seen from above, the

bus rolled counterclockwise (90 degrees about the long axis of the bus) onto its left side

into the ditch parallel to the roadway. The tractor rotated out to the left side of the roadway

with the trailer swinging out behind it. The vehicle came to rest with the tractor and

semitrailer across both lanes of traffic. (See figures 14 and 15.)

None of the vehicle’s passengers was fatally injured. Nine bus passengers

sustained minor injuries, one passenger sustained moderate injuries, one passenger

sustained critical injures, and one passenger and the busdriver were not treated. Details of

the simulation of this accident are provided below.

Simulated Vehicle Dynamics. The simulations revealed that before braking to

avoid hitting the rear end of the bus, the tractor-semitrailer was traveling approximately 60

mph, which was below the posted speed limit of 65 mph. In addition, the bus had probably

just started to accelerate before the accident after dropping off one passenger. The change

in velocity as a result of this collision was 25.2 mph for the bus and 17.1 mph for the

truck. Because the bus underwent changes in angular velocity during the collision, the

total change in velocity experienced by different portions of the vehicle away from the

24 Because the extreme kinematics contributing to neck injuries were not noted in the unrestrained

condition and because the modeling software did not have the capability to measure neck injuries at the time

of the unrestrained simulation, neck injuries were not examined for the unrestrained condition.

25 According to witness interviews, these two occupants may have been standing in the aisle before impact.
School Bus Crashworthiness Issues 25 Special Investigation Report

center of gravity of the vehicle varied. Table 4 details the change in velocity at the center

of gravity of the bus and also at the left rear corner of the bus, where the two ejected

passengers were located.

During the rollover, different accelerations were again experienced along the

length of the bus. The accelerations were much lower than the accelerations seen in the

Monticello simulation, indicating the reduced level of severity of this accident. Table 5

details these accelerations and the positions inside the bus.

Simulated Occupant Kinematics. In general, the simulated occupants first

traveled backward in the bus. Seated simulated occupants contacted the back of the seat.

Unseated simulated occupants continued to travel backward, toward the passenger side of

the bus, due to the bus’ rotation, until contacting a surface such as the sides of seats and

the rear emergency exit door. As the bus continued to rotate and tip over on its side, the

simulated occupants began to slide toward the driver’s side of the bus, where they

subsequently contacted the sides of the seats (since the seats were not directly opposite

one another across the center aisle), the side wall of the bus, or other simulated occupants.

The ejection path and rest positions of the two ejected passengers (seats 8C and 9C

in figure 16) were most closely matched by the simulated occupants when they stood in

the aisle before impact. (See figure 17.) A slight opening of the rear emergency exit door

facilitated the complete ejection of these simulated occupants.26 Higher injury levels were

seen for the two reportedly ejected simulated occupants in the standing position than in the

seated position because they were not protected by the seating compartment. Although the

bus’ accelerations were low, the simulated standing occupants contacted surfaces inside

 Figure 14. Holyoke school bus postaccident damage

26 Witness and passenger reports were not clear concerning whether the emergency exit door of the

school bus had opened during the accident or was opened by rescue workers after the accident. Therefore,

the opening of the rear emergency exit door was investigated for each of the seating positions. The door

position variations simulated were closed, partially (30 degrees) open, and fully open. Impact forces may

have changed the position of the door, but the exact door reactions are unknown.
School Bus Crashworthiness Issues 26 Special Investigation Report

 Figure 15. Holyoke accident scene diagram
School Bus Crashworthiness Issues 27 Special Investigation Report

the vehicle and outside the vehicle not designed to absorb energy and thus were predicted

to sustain injury.

Similar kinematics were noted for both unrestrained and restrained simulated

occupants in the seated, forward facing condition, except that for lap-belted simulated

occupants,27 the pelvis was belted to the seat. During the bus’ rotation and the subsequent

rollover, lap-belted simulated occupants pivoted about the pelvis and then contacted the

seat cushion with the upper body. Predicted injury values were low during this sequence

for all restraint conditions, presumably due to the low accelerations of the bus.

The predicted injuries from the simulation for the two unrestrained conditions, the

two restrained conditions, and the actual injuries sustained by the bus passengers are

shown in table 6.

During the unrestrained simulation of the two reportedly ejected passengers (seats

8C and 9C) standing in the aisle, the two standing simulated occupants were predicted to

sustain head injuries. In addition, the simulated occupant in seat 9F was predicted to

sustain head injuries as the bus overturned and interaction occurred between simulated

Table 4. Peak velocity changes at various locations 

along the bus in the Holyoke accident

Direction Delta V (mph)

Center of Gravity Left Rear Corner

Longitudinal 14 30

Lateral 4 0

Total* 25 40

* Total Delta V determined by the integration of resultant acceleration.

Table 5. Accelerations experienced inside the bus during the rollover 

sequence in the Holyoke accident

Position Acceleration (g)

Longitudinal Lateral Vertical Total

Center of Gravity 0.0 2.6 -1.6 3.2

Seat 8C -0.1 5.7 -0.3 5.8

Seat 8F 1.3 4.1 -4.8 6.8

Seat 9C -0.1 6.5 -0.6 6.6

Seat 9F 1.4 4.8 -5.2 7.2

27 For all simulated occupants, the lap/shoulder belt ran from the lower-left side of the simulated

occupant to the upper-right side of the simulated occupant. (All simulated occupants were seated on the right

side of each bus seat.) Due to this configuration, the upper bodies of the simulated occupants were noted to

slide from the shoulder restraint as the bus began to overturn. Thus, in this accident, the lap/shoulder belts

functioned similarly to lap belts.
School Bus Crashworthiness Issues 28 Special Investigation Report

 Figure 16. Holyoke bus seating diagram
School Bus Crashworthiness Issues 29 Special Investigation Report

occupants. When the two simulated occupants (seats 8C and 9C) were seated, only the

simulated occupant in seat 8C was predicted to sustain a head injury, which would have

occurred as the head contacted the side window during the overturn sequence. Head

injuries were not predicted for any restrained simulated occupant. Chest accelerations

were predicted only for the standing simulated occupant near seat 9C. Neck injuries were

not predicted for any of the simulated occupants in any condition.

The results of this simulation indicate that the majority of the force causing the

simulated occupants to be propelled rearward in the vehicle occurred early in the accident

sequence, as the tractor-semitrailer initially impacted the bus. Therefore, simulated

occupants who were within the seating compartment, even partially, did benefit from the

compartmentalization because the rearward velocity was decreased as they contacted the

seatback. This decrease in rearward velocity reduced the likelihood of ejection out of the

rear emergency exit door in this accident.

 Figure 17. Holyoke simulation time sequence history
School Bus Crashworthiness Issues 30 Special Investigation Report

Holmdel, New Jersey

On September 18, 1998, approximately 7:18 a.m., a 1990 Ford/Thomas Built

body, 54-passenger school bus was traveling eastbound on County Road 520 in Holmdel,

New Jersey, approaching the intersection with State Route 34. The bus was occupied by a

26-year-old unrestrained driver and six passengers, ages 7 to 16. Concurrently, a 1979

Mack, fully loaded dump truck was traveling south on State Route 34 at a driver-estimated

speed of 40 to 45 mph. 

The school bus driver, attempting to make a left turn, entered the intersection on a

red traffic signal and was struck by the truck. The front of the truck contacted the left side

of the school bus at the left front tire. The bus rotated clockwise, and a secondary impact

occurred between the left side of the bus and the right side of the truck. Following the

accident, the truck overturned onto its right side. 

The dump truck impacted the driver’s side of the school bus slightly in front of the

driver’s seat. After striking the school bus, the dump truck began to rotate

counterclockwise. The school bus rotated clockwise and a secondary impact occurred

between the left side of the bus and the right side of the truck. The majority of the damage

occurred on the driver’s side of the bus near the driver’s seat, between approximately the

fifth and sixth rows, where the dump truck overturned onto the top and edge of the bus,

creating a puncture hole. (See figures 18 and 19.)

The busdriver sustained severe injuries during the accident. One passenger

sustained serious injuries. Two passengers sustained moderate injuries, and three

passengers sustained minor injuries. The passenger seats in the school bus were not

equipped with seat belts. Details of the simulation of this accident are provided below.

Table 6. A summary of actual injuries to the Holyoke bus occupants and of predicted 

injuries based on various simulation conditions

Predicted Injuries to Simulated Occupants

Seating 

Location

Body

Segment Actual

Injuries

Unrestrained

 (seated, facing 

forward)

Unrestrained

(8C and 9C 

standing) 

Lap 

Belt

Lap/Shoulder 

Belt

8C

(ejected)

Head

Thorax

Neck

✓✓ ✓

8F Head

Thorax

Neck

9C

(ejected)

Head

Thorax

Neck

✓

✓

✓

✓

9F Head

Thorax

Neck

✓
School Bus Crashworthiness Issues 31 Special Investigation Report

Simulated Vehicle Dynamics. The simulations indicate that the truck was

traveling at approximately 41 mph before impact. The truck began to steer left about 2.6

seconds before impact and then struck the school bus on the left side behind the front left

tire while traveling at a speed of approximately 38.5 mph. The truck experienced an

estimated change in velocity of 11.8 mph and an estimated peak acceleration of 11.3 g at

the center of gravity. 

The school bus was traveling approximately 22 mph when it began to turn into the

intersection and approximately 21.3 mph at impact. The bus’ change in velocity was

estimated at 39.4 mph, and the peak acceleration for the bus was calculated to be 37.9 g at

the center of gravity, an acceleration greater than that calculated for the Monticello

accident. 

The accelerations at different locations inside the bus were also investigated during

this reconstruction. Table 7 details the accelerations experienced at the bus’ center of

gravity as well as at the driver’s seat and on the left and right sides of the first row of

passenger seats. The maximum acceleration at the center of gravity occurred slightly

before the maximum acceleration of the simulated accelerometers placed on the passenger

seats. Therefore, both acceleration values are reported in table 7. The values indicate that

the accelerations at the driver’s seat were greater than those experienced in the row

directly behind the driver. In addition, at these seats, the accelerations were predominantly

lateral.

 Figure 18. Holmdel school bus postaccident damage
School Bus Crashworthiness Issues 32 Special Investigation Report

Simulated Occupant Kinematics. The simulated occupant kinematics

experienced during this accident were similar to those seen in the simulation of the

Monticello accident. In general, the simulated occupants first went diagonally toward the

driver’s side of the bus and slightly forward. (See figure 20.) Those simulated occupants

originally located on the driver’s side of the bus (the side contacted during the collision

 Figure 19. Holmdel accident scene diagram
School Bus Crashworthiness Issues 33 Special Investigation Report

with the dump truck) quickly contacted the side of the bus and the windows. Those on the

opposite side slid across the seat toward the driver’s side, contacting the seat in front (or

the modesty panel) and the sides of the seatbacks (or of the modesty panel), and then

continued into the row in front of the original seating location due to the bus’ kinematics.

Table 7. Peak accelerations experienced inside the bus 

in the Holmdel accident

Position Acceleration (g)

Longitudinal Lateral Total

Center of Gravity -10.3 25.8 28.0

Driver’s Seat 1.2 18.3 18.4

Row 1 Left Side 2.9 11.2 11.6

Row 1 Right Side -4.4 11.0 11.9

CG Maximum -30.1 22.9 37.9

 Figure 20. Holmdel simulation time sequence history (unrestrained condition)
School Bus Crashworthiness Issues 34 Special Investigation Report

The lap belt in this simulation restrained the pelvis of the simulated occupant to the

seat. (See figure 21.) For the two simulated occupants on the opposite side of the bus from

the impact, the kinematics were dramatically altered from the unrestrained condition. The

simulated occupant in seat 1E (see figure 22) did not contact the modesty panel as in the

unrestrained condition. Instead, this simulated occupant rotated about the pelvis and

struck the seat cushion with the head, resulting in a predicted head injury. (The predicted

head injury level in the lap belt-restrained condition was lower than the predicted head

injury level in the unrestrained condition.) Similarly, the simulated occupant in seat 2E

rotated about the pelvis, but because this simulated occupant was larger than the simulated

occupant in 1E, the simulated occupant in seat 2E contacted the seatback in front with the

head concentrating the force of the impact in a small region. This impact resulted in a

predicted head injury for this simulated occupant.

Those simulated occupants on the same side of bus as the impact displayed similar

kinematics to those in the unrestrained condition but had higher predicted injury levels.

The lap belt again acted to restrain the pelvis of these simulated occupants to the seat and

thus allowed smaller portions of the body to absorb the impact energy.

 Figure 21. Holmdel simulation time sequence history (lap belt-restrained condition)
School Bus Crashworthiness Issues 35 Special Investigation Report

In the lap/shoulder belt-restrained condition, although the chest acceleration values

were higher than in the unrestrained condition, the simulated occupants on the opposite

side of the bus from the impact (seats 1E and 2E) were not predicted to sustain head

injuries because the shoulder harnesses were able to restrain the upper torso and thus

 Figure 22. Holmdel bus seating diagram
School Bus Crashworthiness Issues 36 Special Investigation Report

protect the simulated occupants’ heads from impacts within the vehicle. (See figure 23.)

The upper torso did slide from the shoulder restraint, but the trajectory of the upper body

was forward and lateral, whereas for the Monticello accident it was predominately lateral

(as discussed earlier.) Therefore, the velocity of the upper body was reduced enough to

prevent injury before the upper torso slid from the belt. For the simulated occupants on the

same side as the impact (seats 1A and 2A), the levels of predicted injury were similar to

those in the lap belt-restrained condition, although both simulated occupants were

predicted to sustain neck extension injuries in this restraint condition.

The predicted injuries from the simulation for each of the three restraint conditions

and the actual injuries sustained by the bus passengers in the actual accident are

summarized in table 8. These predicted injuries for the unrestrained condition reflect the

kinematics of the sideways positioned simulated occupant in seat 1A. (This orientation

was reported by the passenger seated in 1A.) The simulated occupant in seat 1A was also

placed seated forward facing to enable comparisons to the restrained condition in which

passengers must be forward facing in the simulation.

 Figure 23. Holmdel simulation time sequence history

(lap/shoulder belt-restrained condition)
School Bus Crashworthiness Issues 37 Special Investigation Report

For the unrestrained condition (forward facing in seat 1A), two simulated

occupants were predicted to sustain head injuries. In the lap belt-restrained condition, all

four simulated occupants were predicted to sustain head injuries; in the lap/shoulder beltrestrained condition, two simulated occupants were predicted to sustain head injuries. All

simulated occupants in all restraint conditions except one, seat 2E in the unrestrained

condition, were predicted to sustain chest acceleration values. The unrestrained simulated

occupants were not predicted to sustain neck injuries. One simulated occupant wearing a

lap belt was predicted to sustain a neck injury, while three simulated occupants wearing

lap/shoulder belts were predicted to sustain neck injuries.

Again, the results of this simulation indicate that both lap belts and lap/shoulder

belts may result in injuries not previously seen with compartmentalization alone. The

lower head injury values for the simulated occupants in seats 1E and 2E, as simulated

wearing a lap/shoulder belt, indicate that the potential exists to decrease injuries with

some form of restraint system. Still, care must be exercised to prevent simulated

occupants, who may have sustained minor injuries unrestrained, from being further

injured because of restraints.

School Bus Occupant Crash Protection Systems

In analyzing the most recent large school bus accidents, alternative restraint

systems were investigated that may have mitigated injuries for certain passengers in

particular accidents. However, it may not be possible to accurately predict the level of

injury that would have occurred had a given restraint system been used. Even with a

detailed reconstruction of the accident, the crash pulse experienced by an occupant is

difficult to determine. Lacking this basic information, the speed and direction of an

occupant within the vehicle and the occupant’s impact force onto a contact surface within

the vehicle cannot be known exactly. Assumptions must be made that a restraint system

was used properly (the seat belt was not initially positioned on the abdomen or placed

Table 8. Summary of actual injuries to the Holmdel bus occupants and of predicted 

injuries based on various simulation conditions

Predicted Injuries to Simulated Occupants

Seating 

Location

Body

Segment

Actual 

Injuries

Unrestrained 

(1A sideways) Lap Belt Lap/Shoulder Belt

1A Head

Thorax

Neck

✓

✓

✓

✓

✓

✓

1E Head

Thorax

Neck

✓ ✓

✓

✓

✓

✓

✓

✓

2A Head

Thorax

Neck

✓ ✓

✓

✓

✓

✓

✓

2E Head

Thorax

Neck

✓

✓ ✓

✓
School Bus Crashworthiness Issues 38 Special Investigation Report

against the neck) and that the passenger was seated with correct/ideal posture (front

facing, feet on floor). These assumptions may be critical. An improperly used restraint

system may actually cause more injuries than it prevents.

Intrusion into the bus by the other vehicle is also an important consideration when

analyzing the performance of restraint systems. In the Large School Bus Study, the Safety

Board noted that the most critically injured passengers were seated in the impact zone.

During a collision with multiple impacts, however, the forces of the initial impact may

propel the passenger away from the area of intrusion as the secondary intrusion occurs. To

analyze the severity of injury of a restrained versus an unrestrained occupant requires

comparing the severity of injury due to the intrusive forces of another vehicle into the bus

with the forces experienced by the occupant if propelled from the impact zone. Thus, a

highly accurate simulation is required to determine what the optimal occupant protection

would have been for a specific accident.

Current Occupant Crash Protection

One method by which current poststandard school buses protect the passenger is

through compartmentalization. By virtue of its design, current compartmentalization is

most effective in protecting occupants in frontal and rear impacts in that it keeps the

passenger within the seating compartment. As was discussed earlier,

compartmentalization is accomplished by spacing the seats closely together and by

covering the seat cushions and high seatbacks with an energy-absorbing material. The

entire seat structure is designed to absorb energy and deform to dissipate the energy of the

crash away from the passenger and into the surrounding compartment. The Safety Board’s

1987 Large School Bus Study concluded that current compartmentalization worked well

in the Safety Board-investigated accidents to protect school bus passengers from injuries

in all types of accidents. However, the study also added a caveat regarding three sideimpact (nonrollover) accidents that were investigated:

Unfortunately, due to the nature of these accidents [two minor sideswipe

accidents, one involving a bus equipped with lap belts, and one moderate gradecrossing accident] and the limited data they provided, no judgments as to the level

of occupant protection provided to unrestrained schoolbus passengers in side

impacts could be made, nor could any judgments as the value of lap belts in side

impact be made.

In addition, the 1987 study found that most passengers who were fatally or

seriously injured were seated in the area of intrusion and would not have benefited from

being restrained in their seats.

In this special investigation, four of the school bus accidents28 the Safety Board

investigated were lateral impacts with vehicles of large mass. The Safety Board believes

that the passengers who were retained within the seating compartment (and not in the area

of intrusion) during the accident sequence benefited from compartmentalization

28 Easton, Maryland; Buffalo, Montana; Monticello, Minnesota; and Holmdel, New Jersey. 
School Bus Crashworthiness Issues 39 Special Investigation Report

distributing the impact energy to surfaces designed to absorb that energy. Passengers not

retained within the compartment (not initially in the area of intrusion) impacted surfaces

within the bus not designed to absorb energy. For example, in the Holmdel accident, two

passengers seated just behind the intrusion area remained within the compartment

throughout the accident sequence. Those two passengers sustained minor to moderate

injuries, while the passenger seated on the side opposite the impact sustained serious

injuries as a result of impacting surfaces located outside the compartment. The Safety

Board concludes that school bus passengers who remained within the seating

compartment but not within the intrusion area during the accident sequence were less

likely to have been seriously injured than passengers who were out of the compartment

before the collision or who were propelled from the compartment during the collision. 

The Safety Board is concerned that current compartmentalization, because of its

design, does not protect all passengers during lateral impacts with vehicles of large mass

and during rollovers, especially passengers seated outside the impact area. Occupant

motion analysis of these accidents found that these passengers were being thrown from the

seating compartment toward the area of impact. In addition, if a school bus was hit on the

side or began to rotate during the accident, the passenger may not have directly contacted

the seatback or the seat in front but instead may have slid laterally on the seat. During this

movement, the passenger would have encountered either another passenger, the side walls,

the windows, or the edge of an adjacent seat. Unlike the seating compartment, none of

these surfaces are designed to absorb impact energy. Consequently, passengers striking

these surfaces have a greater chance of injury than when striking the seatback from

behind. This tendency for higher injury could be seen in the Holyoke accident simulation,

where the standing simulated occupants were predicted to impact the rear emergency door,

resulting in a high risk of injury. In the same simulation, those seated within the energyabsorbing compartment adjacent to the standing simulated occupants were predicted to

impact the seatback, resulting in a low risk of injury. Furthermore, had the bus rolled over

during the accident, as in the Flagstaff and Holyoke accidents, the passenger may have

impacted the roof of the bus, the luggage rack, or the tops of the seatbacks. Again, such

surfaces are not designed for impacts. The Safety Board concludes that, because of

compartmentalization, school bus passengers are safer now than they were before 1977.

However, recent accidents lead the Safety Board to further conclude that current

compartmentalization is incomplete in that it does not protect school bus passengers

during lateral impacts with vehicles of large mass and in rollovers because, in such

accidents, passengers do not always remain completely within the seating compartment. 

Alternative School Bus Occupant Protection 

Safety Board staff reviewed information regarding other passenger protection

systems for school buses that are available or may be available in the future: a

lap/shoulder belt system that can be installed on standard school bus seats, a restraining

bar, and a seat with integrated lap/shoulder belts.

A lap/shoulder belt system is currently available that can be retrofitted onto

standard school bus seats. Company literature states that the system meets the testing

requirements of Federal Motor Vehicle Safety Standard (FMVSS) 222, School Bus
School Bus Crashworthiness Issues 40 Special Investigation Report

Passenger Seating and Crash Protection,29 meaning that if a standard school bus seat is

retrofitted with a device and if the device does not change the strength of the seat by its

installation, it meets FMVSS 222 requirements. Because current seatbacks are designed to

deform to absorb the energy of unrestrained occupants, they cannot withstand the loading

of three belted occupants without deforming. Consequently, in a frontal impact, these

lap/shoulder-belted passengers would deform the seat forward through loading of the

restraint system. If an unrestrained passenger were seated behind the belted passengers,

that passenger’s forward motion would not be stopped by the seatback (which usually

occurs in compartmentalization). This unrestrained occupant could then be seriously

injured by impacting interior surfaces within the bus and could also seriously injure the

restrained occupants in front by deforming the seat downward. There are no standards that

an occupant crash protection system must meet when retrofitted onto a school bus seat.

Under current regulations, retrofitting is allowed unless it renders FMVSS 222 ineffective.

A restraining bar is being developed that attaches to the seatback in front of the

seat where the passengers to be restrained are seated. The bar has an automatic locking

feature (pendulum) and looks similar to restraining bars used on amusement park rides.

Company literature states that the bar can be retrofitted onto poststandard school bus seats.

The Safety Board is concerned that the bar, because of its design, will not

effectively restrain the lateral movement of passengers in collisions. In addition, if two

passengers of greatly varying sizes are seated on the same seat, the fit and effectiveness of

the restraint for the smaller passenger would be questionable. Further, company literature

states that “when the bus is in an upright and stable condition, the bar releases.” However,

it is not apparent how passengers would release the restraint if the bus were not in this

position following a rollover-type accident. A company representative stated that if the

bus were in a collision and came to rest on its roof, the passengers should move out from

under the bar at the end of the seat, while upside down. In addition, the restraint bar would

not be totally effective in preventing ejection. The occupants could still move laterally

relative to the seat and, thus, exit the seating compartment and potentially be ejected from

the bus.

Also under development is an integrated lap/shoulder belt system and seat that

would withstand the loading of two restrained passengers. The seat is contoured for two

passengers, with the height-adjusting shoulder portion of the belts anchored in the center

of the seat. Company representatives believe that a seat/restraint system can be developed

to withstand the loading of the restrained passengers and absorb the energy of unrestrained

passengers seated behind the seat without injuring any of the passengers. Although this

occupant restraint system is still in development, a prototype has been manufactured and

tested in a frontal barrier impact scenario. The company would not provide the results of

its testing to the Safety Board. 

The Safety Board is concerned that not all alternative school bus occupant

protection systems under development provide equal protection. Therefore, the Safety

29 For further information on FMVSS applicable to school buses, see appendix B.
School Bus Crashworthiness Issues 41 Special Investigation Report

Board concludes that all potential designs for occupant protection systems to be used on

school buses should be tested to uniform performance standards developed by NHTSA to

ensure occupant safety. The Safety Board believes that in 2 years, NHTSA should develop

performance standards for school bus occupant protection systems that account for frontal

impact collisions, side impact collisions, rear impact collisions, and rollovers. 

As discussed earlier, if a school bus is involved in an accident with large lateral or

rotational forces, current compartmentalization is incomplete and less effective. The

Safety Board’s investigations showed that passengers seated away from the area of impact

may sustain serious injuries as a result of being propelled into the impact area by the

collision forces. Therefore, the Safety Board investigated the issue of passenger restraints,

using computer simulation and injury analysis to determine whether additional forms of

restraint would better protect the passengers in lateral impacts and rollovers. 

Simulated occupants restrained by lap and lap/shoulder belts were compared with

unrestrained simulated occupants to determine the effectiveness of current restraint

systems in large school bus accidents. For example, three simulations were performed for

the Monticello accident restraint analysis: unrestrained, lap belt-restrained, and

lap/shoulder belt-restrained. In the unrestrained condition, three simulated occupants30

were predicted to sustain head injuries. In the lap belt-restrained condition, four simulated

occupants were predicted to sustain head injuries. In the lap/shoulder belt-restrained

condition, five simulated occupants were predicted to sustain head injuries. 

In the lap belt-restrained simulation, the lap belt restrained the simulated

occupant’s pelvis relative to the seat but did not restrain the upper torso. Due to the

unrestrained movement of the upper torso, impact forces were concentrated on small areas

of the upper body, such as the head. These concentrated forces resulted in a predicted high

risk of head injury. In the lap/shoulder belt-restrained simulation, for the occupants seated

on the side of the bus opposite the third impact, the simulated occupant’s upper torso was

predicted to slide laterally out of the shoulder harness. The resulting simulated occupant

motion was similar to that seen in the lap belt-restrained condition. In the unrestrained

condition, impact forces were distributed over a large portion of the simulated occupant’s

body. The distribution of impact forces resulted in a reduced risk of head injuries. Similar

findings were noted for the Holmdel, New Jersey, accident. Thus, the potential exists for

an increased risk of injury to occupants restrained using typical seat belt designs.

However, because injuries occurred for all restraint conditions in the simulated accidents

and because injury levels varied depending upon occupant kinematics and seating

location, the Safety Board concludes that it cannot be determined whether the current

design of available restraint systems for large school buses would have reduced the risk of

injury to the school bus passengers in these accidents. Even though the Safety Board was

unable to determine whether current restraint systems would have decreased injury levels

in these accidents, potential crash protection systems that would better protect occupants

are possible. For example, in the Holmdel simulation, the reduced head injuries seen for

the simulated occupants seated on the opposite side of the bus from the impact and

30 These simulated occupants were seated in the same locations as the actual passengers who sustained

head injuries in the actual accident.
School Bus Crashworthiness Issues 42 Special Investigation Report

restrained in lap/shoulder belts indicate that injuries could possibly be decreased with

some form of restraint system. Therefore, the Safety Board further concludes that the

potential exists for an occupant crash protection system to be developed that would protect

school bus passengers in most accident scenarios. The Safety Board believes that once

pertinent standards have been developed for school bus occupant protection systems,

NHTSA should require newly manufactured school buses to have an occupant crash

protection system that meets the newly developed performance standards and retains

passengers, including those in child safety restraint systems,31 within the seating

compartment throughout the accident sequence for all accident scenarios.

31 Any device (except a passenger system lap seat belt or lap/shoulder belt) designed for use in a motor

vehicle to restrain, seat, or position a child who weighs less than 50 pounds.
43 Special Investigation Report

Motorcoach Crashworthiness Issues

In the course of investigating three recent, severe motorcoach accidents,32 the

Safety Board became concerned that motorcoach passengers are not adequately protected

in collisions. Although Federal Motor Vehicle Safety Standards (FMVSS) exist for large

school buses relating to passenger seating, crash protection, and body joint strength, no

similar standards apply to other types of large buses, including motorcoaches. In other

words, no Federal regulation or standard requires that large buses sold or operated in the

United States be equipped with active or passive occupant protection (other than for the

driver).

From 1968 through 1973, the Safety Board issued 11 recommendations33 to the

Federal Highway Administration (FHWA), the National Highway Traffic Safety

Administration (NHTSA), or both, concerning restraints, including requiring that seat

belts be installed in buses. These recommendations have not been implemented by either

NHTSA or the FHWA, who have cited reasons such as:

• Seat belts would be impractical because buses are not designed for their use and

cannot withstand floor loadings;

• The small number of deaths or injuries in bus accidents do not justify the

installation of restraints;

• Tests conducted by the Bureau of Motor Carrier Safety (BMCS)34 indicate that

belts would be used by only a small percentage of passengers;

• New FMVSS relating to bus emergency exits, window retention and release,

improved seating, and crash protection in new buses would be more effective,

less costly, and more easily accepted by the public.35.

The last recommendation made by the Safety Board regarding occupant restraints

in motorcoaches (Safety Recommendation H-73-42) was placed in a “Closed—

Reconsidered” status on June 29, 1988, with a provision that the Safety Board continue to

monitor motorcoach accidents to determine whether the installation and use of occupant

restraints would mitigate injuries. Since this time, the Safety Board has continued to

investigate motorcoach accidents in which passengers sustained serious injuries and

fatalities from ejections and rollovers. 

32 Accident No. HWY-98-MH-033, Burnt Cabins, Pennsylvania, June 20, 1998; Accident No.

HWY-99-MH-007, Old Bridge, New Jersey, December 24, 1998; and Accident No. HWY-99-MH-017,

New Orleans, Louisiana, May 5, 1999. 

33 These recommendations (H-68-18; H-70-4; H-71-10 and -11, H-71-34, -35, and -87; and H-73-1, -7,

-18, and -42) are summarized in appendix E. 34 Predecessor of the Office of Motor Carrier and Highway Safety.

35 FHWA letter dated February 11, 1974.
Motorcoach Crashworthiness Issues 44 Special Investigation Report

In light of concerns raised about passenger safety by the current accident

investigations, the Safety Board initiated this special investigation to reexamine the issue

of seat belts in motorcoaches. In addition, more information and crash test data have

become available on seat belts, specifically seat belts on motorcoaches. Much of this

research has been conducted in Australia36 and in the European Union (EU),37 where

passenger seat belts are now mandatory on motorcoaches.38 In the United States, no fullscale crash testing of a motorcoach has been conducted since 1965. 

Active Occupant Crash Protection

The Safety Board has long been interested in the issue of occupant restraints on

motorcoaches. Appendix E summarizes this history with a table containing applicable

Safety Board recommendations, including their status and NHTSA’s and the FHWA’s

responses to them. Many of the reasons given for not requiring that restraints be installed

on motorcoaches are no longer valid. In addition, many of the alternative measures

promised were not carried through.

As an example, one of NHTSA’s responses (March 21, 1973) to Safety

Recommendation H-73-1 to incorporate seat belts on motorcoaches stated: 

With regard to the recommendation to provide seat belts for all passengers on

intercity buses, you may be interested in the recent Notice of Proposed

Rulemaking Bus Passenger Seating and Crash Protection printed...February 22,

1973. The National Highway Traffic Safety Administration in this proposal would

require bus passenger seats which are stronger and safer and which afford greater

protection to bus passengers. The standard as proposed would apply to buses of all

types manufactured after September 1, 1974. 

However, when the second notice of proposed rulemaking (NPRM) was issued on

July 30, 1974, only large school buses were included in the proposed requirements.

NHTSA determined that seating requirements for intercity and transit buses were not

justified based upon cost-benefit studies. 

On May 2, 1979, the FHWA advised the Safety Board that a 1963 study by the

American Bus Association (ABA) and the FHWA’s BMCS indicated that only 42 percent

of passengers on a test trip used available lap belts during a portion of the trip, while only

25 percent used their available belts for the entire trip. The Administrator further advised

36 Lap/shoulder belts have been required on newly manufactured motorcoaches since 1994 in

accordance with Australian Design Standard No. 68. 37 EU member states (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Italy, Ireland,

Luxembourg, the Netherlands, Portugal, Spain, Sweden, and the United Kingdom) require either lap belts

(two-point belts) and an energy-absorbing seat or lap/shoulder belts (three-point belts). The seat belt

directive that became effective October 1, 1997, specifies that a Member state can require motorcoaches to

meet national legislation on seat belts. However, the directive further specifies that unless the vehicle is a

new design, it does not have to meet the legislation’s requirements until October 1, 1999, and that a Member

state can set different standards until that date.

38 For more information on European and Australian legislation and initiatives, see appendix D.
Motorcoach Crashworthiness Issues 45 Special Investigation Report

that a 1973 study by the ABA and the BMCS indicated that only 7.2 percent of the

passengers had used available lap belts during a test trip. Yet, the FHWA decided to

reconsider requiring lap belts in certain passenger positions (first two rows) if a costbenefit analysis showed it would be beneficial. The Administrator informed the Safety

Board that an NPRM would be published soliciting comments and information on

requiring lap belts at specific seats in buses. 

On May 31, 1979, a copy of a draft NPRM was furnished to the Safety Board, and

on June 7, 1979, the FHWA’s Associate Administrator for Safety sent a letter noting that

“we are planning to issue a notice in the Federal Register asking for comments on the

merit of initiating rulemaking to require lap safety belts at selected locations (in buses).”

However, this notice was never published.

The latest NHTSA data estimate that, in 1997, the seat belt usage rate in the United

States was 69 percent, a significant increase from the 1963 and 1973 studies cited by the

FHWA. This increase indicates that the argument that the public is not in the habit of using

seat belts can no longer be used as a reason for not equipping motorcoaches with

restraints.

Safety Board-Investigated Accidents 

Thirty-six motorcoach accidents investigated by the Safety Board from 1968

through 1997 are summarized in appendix F. These 36 motorcoach accidents resulted in

168 occupant fatalities. One accident, which involved fire in the passenger compartment

(case 1), resulted in 19 occupant fatalities. Of the remaining 149 occupant fatalities, 106

occurred in accidents involving a rollover. Of these 106 fatally injured passengers, 64

were ejected from the motorcoach.

In 8 of the 36 accidents (cases 2 through 8 and 13), the Safety Board concluded

that passenger restraints would have reduced or prevented injuries or fatalities. Of those

eight accidents, seven involved a rollover. All of these accidents occurred before June

1988, when the Board classified the most recent restraint recommendation, H-73-42,

“Closed—Reconsidered,” based upon findings from the Safety Board accident

investigations up to that point.39 Sixteen motorcoach accidents were investigated after this

recommendation was closed. Twelve of these accidents involved a rollover and resulted in

22 fatalities, 16 of which were ejections. In the four remaining accidents, which did not

involve a rollover, five of the six fatally injured passengers were ejected.

Occupant Kinematics in Motorcoach Rollovers

The injury mechanisms in rollovers are similar to other types of collisions in that

the injury severity is related to how fast the occupant is moving and how quickly the

occupant stops. The injury tolerance level of an individual (which is based on age, health,

39 The Safety Board found in accidents involving front and rear collisions (as opposed to rollovers) that

restraints generally did not lessen injury outcome for passengers who sustained minor to moderate injuries

and that their effect could not conclusively be predicted for more seriously injured passengers. The Safety

Board noted that it would continue to monitor rollover accidents for the potential benefits of restraints.
Motorcoach Crashworthiness Issues 46 Special Investigation Report

and bone density) is also a factor, as are (1) the orientation of the occupant’s body at

impact; (2) the distance over which the occupant decelerates; and (3) the objects struck by

the occupant within the vehicle. 

The occupant’s orientation at impact is important because the human body’s

tolerance to impact varies. For example, the orientation of the head relative to the body at

impact may greatly increase the chances of neck injury.

The second factor is the proximity of the occupant to the portion of the vehicle

experiencing the high velocity change. For instance, if an occupant’s head is against the

roof rail as its strikes the ground, the occupant’s head undergoes the same acceleration as

the roof rail does as it strikes the ground. However, another occupant in the same bus who

is tumbling about the interior cabin and is not in contact with any portion of the vehicle

may not experience the forces associated with the roof’s impact with the ground. 

In addition to hazards inside the vehicle, occupants in a rollover risk being ejected.

When ejected from the relative safety of the vehicle interior, the occupant risks being

struck by that vehicle or another vehicle on the roadway.

Occupant Kinematics in Motorcoach Ejections

The injury mechanisms of a passenger who is ejected are similar to those of a

passenger who is tumbling about the interior. Again, the orientation of the passenger when

striking the ground outside is an important factor. A passenger who remains in the vehicle

will strike the interior surfaces at a velocity relative to the interior of the vehicle. An

ejected passenger will strike the ground at a velocity relative to the ground. For instance, if

a bus that is traveling at 60 mph collides with a vehicle and is slowed to 50 mph by the

impact, the maximum velocity at which a passenger can strike interior surfaces is 10 mph.

Yet, a passenger who is ejected from the vehicle can strike the ground at a relative velocity

of 60 mph (assuming nothing slowed the passenger during ejection). Furthermore,

passengers who are ejected risk being struck by the bus or another vehicle or other

harmful objects. 

Based upon the Safety Board’s investigations of motorcoach accidents and based

upon the dynamics of rollovers and occupant ejection, the Safety Board concludes that one

of the primary causes of preventable injury in motorcoach accidents involving a rollover,

ejection, or both is occupant motion out of the seat during a collision when no intrusion

occurs into the seating area. Thus, the Safety Board concludes that the overall injury risk

to occupants in motorcoach accidents involving rollover and ejection may be reduced

significantly by retaining the occupant in the seating compartment throughout the

collision. The Safety Board therefore believes once pertinent standards have been

developed for motorcoach occupant protection systems, that NHTSA should require

newly manufactured motorcoaches to have an occupant crash protection system that meets

the newly developed performance standards and retains passengers, including those in

child safety restraint systems, within the seating compartment throughout the accident

sequence for all accident scenarios. 
Motorcoach Crashworthiness Issues 47 Special Investigation Report

Seat Belts

Seat belts are a common method of restraining occupants in their seats during an

accident. However, motorcoaches in the United States are not required to be equipped

with seat belts, and few are. Only 2 of the 36 motorcoach accidents that the Safety Board

investigated involved motorcoaches equipped with passenger seat belts. In both cases,

restraints were available only in the front-row passenger positions. (See cases 26 and 36 in

appendix F. ) In both cases, the passengers were not wearing the available restraints.

Seat Belts on Motorcoaches in the EU. As was noted earlier, the EU enacted

legislation in June 1996 requiring that new motorcoaches be fitted with seat belts at all

passenger positions. The primary intent of this legislation was to reduce fatalities due to

ejection. 

The lap belts installed on the European-style buses40 are attached to the seat.

Because of this, the ultimate ability of the seat/restraint system to retain the occupants is

determined by the strength of the seat, the restraint system, and strength of the seat

anchorages. The minimum seat anchorage system strength required for seats with

integrated restraints in the EU is less than that required for U.S. automobiles. According to

researchers who assisted in the development of the EU regulation, this lower limit was

established based upon the UNECER80 crash pulse.

41 This crash pulse was chosen

because it appeared to be a reasonable criterion, given a motorcoach’s size and structure.

In the EU, researchers believed that the crash pulse in a motorcoach is less than in an

automobile, thus the seat anchorage strength could be less.

The EU conducted no dynamic crash testing of buses in support of its occupant

restraint system design. Further, no dynamic crash testing of buses is required of

manufacturers by the legislation. Although a researcher stated that the crash pulse was

thought to be supported by dynamic crash testing of motorcoaches, no one was able to

refer to actual crash tests. Sled testing was performed in support of this regulation at the

Cranfield Impact Centre42 using the UNECER80 crash pulse. 

The lap belt was used because researchers at the Cranfield Impact Centre, which

helped develop the EU requirements, thought it would be too difficult and not costeffective to have a seat that was both energy absorbing and equipped with lap/shoulder

belts. Since the regulation was developed, Cranfield Impact Centre researchers have

developed a seat that is energy absorbing, incorporates lap/shoulder belts, is cost effective,

and tests well when subjected to a UNECER80 crash pulse.

40 A European motorcoach is typically equipped with one rear axle, a floor-level emergency door on the

right side, a roof-mounted air conditioner unit, and tempered side windows. 41 United Nations/Economic Commission of Europe (UNECE) Regulation (UNECER) 80 specifies

anchorage strength for motorcoaches. UNECE requirements can be adopted by any United Nations member

state but are not mandatory. The UNECER80 crash pulse refers to the specifications for sled decelerations

defined in UNECER80, which allow for a range of decelerations over a given time. 42 The Cranfield Impact Centre is a consulting company owned by Cranfield University, located near

Bedford, England.
Motorcoach Crashworthiness Issues 48 Special Investigation Report

Seat Belts on Motorcoaches in Australia. In 1992, the Australian Government

enacted legislation requiring lap/shoulder belts at all passenger positions for motorcoaches

manufactured since 1994. Initially, Australia had intended to adopt an anchorage standard

similar to the EU’s. However, upon learning that the Stratos Seat Company had developed

a seat that tested well when subjected to a crash pulse deceleration approximately twice

the European requirement, that incorporated lap/shoulder belts, that could withstand an

impact from behind by unbelted occupants (not an EU requirement), and that could be

installed in motorcoaches at an affordable price, the Australians revised the standard to

incorporate these conditions. Like the EU, Australia conducted no dynamic crash testing

of motorcoaches in support of its regulation.

An accident involving a motorcoach equipped with the new restraint system

occurred on January 7, 1997, in Tenterfield, Australia. This was a single-vehicle accident

in which the motorcoach struck a culvert. The court report states that motorcoach was

equipped with a Tripmaster computer (on-board vehicle recording system) that indicated

the motorcoach was traveling 53 mph at impact and that no pre-impact braking occurred.

According to the report filed by the principal engineer,43 the motorcoach traveled 47.6 feet

from the initial point of impact and sustained 3.3 feet of crush in the accident. Two

passengers were fatally injured, both of whom were not restrained. One fatally injured

passenger was walking down the aisle before the collision, and the other one was sleeping

in the sleeping berth at the rear of the bus.

Global Harmonization. In June 1998, the United States became the first party in a

UNECE agreement to establish harmonized global technical regulations for motorized

vehicles. The purpose of the agreement is to determine the highest vehicle safety practices

in the world against which to model the global regulations.

On January 5, 1999,44 NHTSA solicited comments on its draft policy statement

concerning priorities for implementing the 1998 agreement on the global technical

regulations. This notice stated that, in May 1998, NHTSA had published a final rule 

reaffirming its policy of focusing its international harmonization activities on

identifying those foreign vehicle safety standards that clearly reflect best

practices, i.e., that require significantly higher levels of safety performance than

the counterpart U.S. standard. NHTSA’s policy is to upgrade its standards to the

level of those foreign standards.

The Safety Board is convinced that this policy will result in safer motor vehicles in

the United States and in other countries that participate in the UNECE agreement. 

43 Report on Inspection of MCA Bus From Tenterfield Crash, Vehicle Standards R&D, Federal Office of

Road Safety, Department of Transport and Regional Development, Canberra, Australia.

44 Docket no. NHTSA-98-4956, notice 1, RIN 2127-AH29.
Motorcoach Crashworthiness Issues 49 Special Investigation Report

Lap Belts in Passenger Cars. A NHTSA study,45 based on Fatality Analysis

Reporting System (FARS) data from January 1988 through June 1997, examined the

effectiveness of restraints at the rear seat outboard seating positions of passenger cars.

According to the data, lap/shoulder belts are 77 percent effective in preventing fatalities in

rollover accidents. This effectiveness does not come entirely from ejection reduction,

since lap/shoulder belts are also 54 percent effective in reducing fatalities among

passengers who remain in the vehicle during the rollover and are 28 percent effective in

preventing passenger fatalities in frontal collisions. 

The study also determined that lap belts at the rear outboard position in passengers

cars are 76 percent effective in reducing fatalities in rollover accidents. However, lap belts

were found to have an overall negative effect in frontal collisions, meaning that

passengers in lap belts only are more likely to be fatally injured than those who are

unbelted. These findings are consistent with earlier Safety Board findings46 regarding lap

belts that indicated that lap belts could have negative effects. 

Motorcoach Crash Testing

Dynamic Rollover Crash Testing of Motorcoaches. A dynamic rollover test of

a motorcoach was conducted in Germany in August 1995 by DEKRA,47 a private-sector

vehicle monitoring organization, using belted and unbelted 50th-percentile dummies. In

the test, the dummies were placed in aisle side seats opposite the side of the bus that

impacted the ground. The motorcoach was then dragged over a ramp at 40 kph (25 mph),

causing it to roll onto its left side. The lap-belted dummies remained in their belts during

the rollover and sustained lower head injury levels, as well as lower peak chest and pelvis

decelerations, than the unbelted dummies. The test dummy that received the highest level

of head injury was unbelted, and the predicted injury was the result of the dummy’s head

striking the luggage rack. 

DEKRA’s testing48 also references two other rollover tests, one with a static

overturn tested in compliance with UNECER66,49 the other based on numerical

simulations. Both of these tests support the contention that lap belts are beneficial on seats

that turn upward as a result of being on the rising side of an overturning motorcoach. 

45 NHTSA Technical Report, Effectiveness of Lap/Shoulder Belts in the Back Outbound Seating

Positions, June 1999, DOT HS 808945.

46 For further information, read Safety Study—Performance of Lap Belts in 26 Frontal Crashes,

NTSB/SS-86/03, Washington, DC. 47 DEKRA stands for Deutscher Kraftfahrzeug-Überwachungs Verein (loosely translated, “German

Vehicle-Monitoring Association”). 48 Berg, F. Alexander, and Niewöhner, Walter, “Pointers Toward the Improvement of Safety in Buses,

Derived From an Analysis of 371 Accidents Involving Buses in Germany and From Crash Test Results,”

Paper No. 98-S4-O-03 (DEKRA Automobile AG, Germany), Proceedings of the 16th International

Technical Conference on the Enhanced Safety of Vehicles (ESV), Windsor, Ontario, Canada, May 31 through

June 4, 1998, vol. 2, 791-806.

49 UNECE Regulation 66 governs roof-strength requirements for motorcoaches.
Motorcoach Crashworthiness Issues 50 Special Investigation Report

The report’s conclusions are less clear on the issue of lap/shoulder belts

and cautions:

The particular dynamic with side overturns and rollovers can lead to the torso of

the belted passenger becoming free from the shoulder strap. This causes the entire

belt to come loose and there is also a risk of passengers becoming released by the

belt around the hips.

Concerns about lap belts were also raised. The report specifically states that for

passengers seated on the side of the bus that impacts the ground during rollover, a lap belt

alone cannot prevent the head, torso, arms, and hands of passengers from colliding with

the rails or side windows. In addition, if the side structure breaks, the occupant’s risk of

striking the ground and sustaining severe injury are increased. However, the report cites

research50 indicating that passengers seated next to the window could be protected from

partial ejection hazards by lap/shoulder belts that are properly tightened and fitted to

prevent this occurrence. 

Frontal Dynamic Crash Testing. Two dynamic frontal crash tests involving

motorcoaches were performed by DEKRA. Both of the tests involved motorcoaches

designed for the European market. The first test (conducted in November 1993) involved a

motorcoach that struck the rear of a truck at approximately 25 mph; the second test

(conducted in August 1994) involved a motorcoach that struck a fixed barrier at

approximately 19 mph, with approximately 30 percent overlap. The peak deceleration in

these tests was approximately 12 g and was of relatively short duration. During most of

the impact duration, the deceleration was below 6 g. This report51 stated:

The flexibility of the front structure of the bus leads to relatively low levels of

deceleration in the passenger area behind. This means belted and unbelted

occupants are at relatively low risk of injury. Especially, when there is sufficient

room in the front of the seat for the head and torso to move, lap belts can offer

passengers protection in event of front collisions with the bus. If the back rest of

the other seats are positioned in front of the passenger, it must be insured that no

awkwardly positioned and designed component present a risk of injury.

Seat Belt Analysis

As was concluded earlier in this special investigation in the discussion on occupant

kinematics in ejections and rollover, one of the primary causes of preventable injury in

motorcoach accidents involving a rollover, ejection, or both, is occupant motion out of the

seat during a collision when no intrusion occurs into the seating area. Further, injuries and

fatalities may be reduced significantly in motorcoach collisions by retaining passengers in

their seats throughout the collision.

50 Grösch, Lothar, Mattes, Bernhard, and Schramm, Dieter, “Smart Restraint Management and

Comprehensive Concept,” Proceedings of the International Symposium on Sophisticated Car Occupant

Safety Systems Airbag 2000, Karlsruhe, Germany, November 26 through 27, 1996, pp. 16-1 through -20.

51 Berg and Niewöhner, 791-806.
Motorcoach Crashworthiness Issues 51 Special Investigation Report

Australia and the EU now require seat belts on motorcoaches. The EU’s regulation

requires that motorcoaches be fitted with lap belts or lap/shoulder belts at each passenger

position. Australia’s regulation requires lap/shoulder belts at all passenger positions.

Although crash testing was not performed in support of these regulations, a limited

number of frontal and rollover motorcoach crash tests have been performed in Germany.

The analysis of data available from these tests and sled testing performed at Cranfield

Impact Centre raise concerns that the lap belts (two-point restraints) used in these tests

could increase the potential for injury in frontal collisions for certain seat spacing or if the

seatback in front of the occupant were incorrectly designed.

The lap/shoulder (three-point) occupant restraint system required in Australia and

the one designed by the Cranfield Impact Centre demonstrate the ability to design

lap/shoulder restraint systems for motorcoaches. NHTSA has stated in its global

harmonization policy that it would identify the best international practices and upgrade to

those standards. The Safety Board agrees with this principle and agrees that the most

advanced technology should be utilized when designing new occupant restraint systems. 

The EU and Australian occupant crash protection regulations were based on sled

testing. Actual dynamic testing of motorcoaches was not conducted to determine the

effectiveness of restraint systems as occupant protection systems.

Occupant protection systems should be tested to performance standards before

their implementation to ensure that they are beneficial and to guard against possible

negative effects such as have occurred in the rear seats of automobiles in frontal collisions.

The Safety Board concludes that new occupant crash protection systems for motorcoaches

should be tested to uniform performance standards developed by NHTSA that are based

upon actual crash testing of motorcoaches to ensure occupant safety. The Safety Board

believes that in 2 years, NHTSA should develop performance standards for motorcoach

occupant protection systems that account for frontal impact collisions, side impact

collisions, rear impact collisions, and rollovers. 

Passive Occupant Crash Protection

Passive occupant protection refers to protective devices that require no action by

the occupant to implement. Current passive safety features on automobiles include airbags

and energy-absorbing materials on interior surfaces. Because these measures require no

occupant action, they are appealing as the starting point of an occupant crash protection

system. In the following sections, passive protection measures designed to reduce injuries

of motorcoach passengers and to prevent passenger ejections are examined. These

measures include window size and glazing and roof strength.

Window Glazing

On November 29, 1988, a chartered 1987 Motor Coach Industries (MCI)

motorcoach was traveling southbound in the express lane of the New Jersey Garden State

Parkway when it gradually veered to the right off the travel lane, sideswiped a guardrail,

and skidded back onto the highway.52 After returning to the highway, the motorcoach
Motorcoach Crashworthiness Issues 52 Special Investigation Report

overturned onto its right side and slid approximately 220 feet across two express lanes

before coming to rest.

The side windows of the motorcoach were made of abrasive-resistant, coated

acrylic. During the overturn, the 27 passengers seated on the left side of the motorcoach

were thrown from their seats and fell on top of the 22 passengers seated on the right side

of the motorcoach. The passengers became entangled on the right side of the motorcoach

as it slid across the highway before coming to rest. None of the passengers were ejected.

The injuries sustained ranged from minor to severe and included fractured ribs,

lacerations, abrasions, and contusions. Sixteen passengers were hospitalized. The driver

stated he was not wearing the available lap belt and was partially ejected through the

driver’s side of the broken windshield.

The Safety Board determined that if the side windows had been equipped with the

more commonly used tempered safety glass, they might have broken during the

motorcoach overturn, subjecting the occupants to contact with the road surface. Because

the acrylic windows did not break, they may have prevented occupants from contacting

the road surface and sustaining more serious or even fatal injuries. 

As a result of this investigation, the Safety Board issued Recommendation

H-89-16 to the United Bus Owners of America (UBOA)53 and the ABA. The

recommendation requested that UBOA and the ABA advise their members of the potential

safety benefits of the use of abrasion-resistant, coated acrylic windows in protecting bus

occupants in overturns. Because these organizations responded by publishing the

requested information in their organizations’ newsletters, the Safety Board classified

Safety Recommendation H-89-16 “Closed—Acceptable Action” on June 22, 1990, for the

ABA, and on June 28, 1990, for UBOA. 

Since 1993, NHTSA has conducted an ongoing research project concerning

ejection mitigation, Improved Glazing for Reducing Ejection. The objectives of this

research are to determine whether improved side window glazing in passenger cars, light

trucks, and vans, would reduce the possibility of full or partial ejection and to determine

whether such glazing should be regulated by NHTSA. A NHTSA status report54 published

in 1995 estimated that advanced glazing composed of glass and plastic could save 1,313

lives and prevent 1,297 serious injuries per year in passenger cars. Some of the glazing

tested did increase the potential for head injuries as compared with tempered glass, which

is currently used in most side windows of cars, trucks, and vans. In the report, NHTSA

recommended continuing research by expanding the computer modeling and prototype

testing. A second status report on the agency’s ejection mitigation research is currently

undergoing internal review.

52 For further information, read Highway Accident Summary Report—Intercity-Type Buses Chartered

for Service to Atlantic City, New Jersey, HAR-89/01/SUM, Washington, DC. 53 The United Bus Owners of America is now the United Motorcoach Association (UMA). 

54 Ejection Mitigation Using Advanced Glazing, Status Report, NHTSA, Washington, DC, November, 1995.
Motorcoach Crashworthiness Issues 53 Special Investigation Report

Some of the design limitations encountered when utilizing the glazing in

automotive windows do not apply to motorcoach side windows. For instance, in an

automobile, the side window glazing can be supported only on three sides. In addition, an

automobile side window must withstand the constant use of being raised and lowered

within the frame. In contrast, the side window glazing in a motorcoach remains stationary

and can be bonded to the frame.

The DEKRA report55 on motorcoach rollovers and restrained occupants raised

concerns about lap belts. The report stated that lap belts may not prevent the head, torso,

arms, and hands of passengers seated on the side of the bus that impacts the ground during

rollover from colliding with the rails or side windows. In accidents where the side

structure breaks, the occupant’s risk of striking the ground and sustaining severe injury are

increased. The Safety Board concludes that equipping motorcoach side windows with

advanced glazing may decrease the number of ejections of unrestrained passengers during

motorcoach accidents and decrease the risk of serious injuries to restrained passengers

during motorcoach accidents. The Safety Board believes that NHTSA should expand its

research on current advanced glazing to include its applicability to motorcoach occupant

ejection prevention, and revise window glazing requirements for newly manufactured

motorcoaches based on the results of this research.

Motorcoach Roof Strength and Window Size

No FMVSS exist that either limit a window’s maximum size in any type of bus

(including school buses) or, except in the case of large school buses, address rollover

strength in motorcoaches. In the 1970s, the Safety Board raised concerns about the

relationship between increased window size and roof strength. This concern focused

primarily upon the decrease in the number of vertical supports between windows or roof

bows that accompanied the increase in window size.

Passenger-Side Window Size. Buses manufactured after September 1, 1973, are

required to comply with the FMVSS 217 (49 Code of Federal Regulations [CFR]

571.217) requirement that emergency exits on buses have an opening large enough for

unobstructed passage.56 Although FMVSS 217 contains requirements for minimum bus

emergency exit size and for window retention and release, no maximum window size is

specified.

Safety Board staff measured the passenger windows of motorcoaches

manufactured by Thomas Built, Dina, MCI, Van Hool, Setra, and Prevost to determine the

current average size of motorcoach passenger windows.57 Staff found that the average

window area is 2,040 square inches,58 indicating that the “average” motorcoach side

55 Berg and Niewöhner, 791-806. 56 An ellipse having a major axis of 19.68 inches and a minor axis of 12.99 inches, or a computed area of

200.8 square inches.

57 To account for differences in securing methods, as well as for varying frame dimensions, only the

horizontal and vertical dimensions of the transparent glazing itself were measured. This method simulates

the opening size created if the glazing were completely broken out while the window frame remained

attached to the motorcoach body.
Motorcoach Crashworthiness Issues 54 Special Investigation Report

window is 10 times larger than is required to meet the emergency exit standard under

FMVSS 217. The size difference does not include allowances for framing and/or gaskets

in the motorcoach windows. In addition, the size of the opening would increase if the

window framing or gasket were ejected or if the window were an emergency exit and

came open during a rollover. 

Roof-Strength Issues. On October 10, 1971, a 1970 MCI motorcoach was

traveling westbound on U.S. 66 near Marshfield, Missouri, when it collided with the left

side of a station wagon in the westbound lanes of the four-lane, divided highway.59 After

impact, the motorcoach rotated clockwise (as seen from above) and skidded

approximately 150 feet, left the pavement, and crossed the shoulder. It then vaulted into a

drainage ditch, rolled 1 1⁄4 times, and came to rest on its left side. Four passengers were

fatally injured, including one of five passengers ejected through the side windows. A

collapsed roof crushed two passengers. The remaining 33 passengers and the driver

sustained moderate to severe injuries.

For that accident, the Safety Board determined that the availability and use of seat

belts or another form of restraint by the passengers would have reduced the numbers of

injuries and fatalities. In addition, the investigation determined that during the rollover,

gross downward and sideward deflection of the roof occurred and the roof support design

caused the side-window posts to fail due to concentrated loads. The Safety Board

concluded that the strength of the roof support structure for “picture-window” type buses

are inadequate.

As a result of the investigation, the Safety Board recommended that newly

constructed interstate-type buses be equipped with approved occupant restraints (Safety

Recommendation H-73-1) and made two additional recommendations in 1973 regarding

rollover strength and window size:

H-73-3

The Bureau of Motor Carrier Safety (BMCS), Federal Highway Administration,

review intercity bus design and the types of damage suffered in rollover accidents

in an attempt to determine whether structural strength in the window areas may

have been reduced in recent years in buses having very large side windows; and

that BMCS prepare a rollover performance test, or other performance tests, for

buses which can reveal the structural strength of buses in the areas stressed by

rollover.

H-73-4

The manufacturers of intercity buses review their existing designs of buses having

very large side windows to determine whether it is technically feasible to prevent

critical localized structural failures and to increase the general strength of the

58 The average window width is 60 inches, and the average window height is 34 inches.

59 For additional information, read Highway Accident Report—Bus/Station Wagon Collision Followed

by Bus Overturn, U.S. Route 66, Near Marshfield, Missouri, October 10, 1971, NTSB-HAR-73-1,

Washington, DC. 
Motorcoach Crashworthiness Issues 55 Special Investigation Report

window area of buses: by the use of greater-strength window columns; by

employing a larger number of continuous structural members through the window

area; and by using smaller windows.

In its March 23, 1973, letter responding to these recommendations, the FHWA

stated that the BMCS had no funds to perform the rollover testing suggested by Safety

Recommendation H-73-3, noting “Such tests have merit and will be considered for future

research funding requests.” Regarding Safety Recommendation 73-4, the FHWA stated

“...we concur in the thrust of this recommendation. We shall undertake a review of our

window glazing requirements to determine if the matter should be set for rulemaking.”

Consequently, the Safety Board classified Safety Recommendations H-73-3 and -4

“Closed—Acceptable Action” on January 1, 1980. As was mentioned earlier in this

section, NHTSA has been performing research since 1993 on window glazing for

passenger cars and light trucks, the method of improving window strength cited by the

FHWA in its 1973 response to Safety Recommendation H-73-4. However, almost 20 years

after Safety Recommendations H-73-3 and -4 were closed, rollover testing on

motorcoaches has yet to be performed. 

The EU has proposed legislation, based on UNECER 66, concerning the rollover

strength of buses and motorcoaches. The European Commission (the Commission) believes

that a directive on rollover strength in the bus construction standards is essential for ensuring

the effectiveness of the seat belt legislation. The Commission also believes that mandating

seat belts without a rollover strength requirement exposes passengers to potential injuries if

the roof crushes downward and decreases the available occupant space, as would occur

during a 180-degree or greater rollovers. At present, only the United Kingdom and Spain

require mandatory compliance with the Commission’s rollover strength requirements.

As was noted in the preceding section on window size, the size of passenger

windows continues to increase. As window size increases, the number of vertical supports

between windows decreases. Thus, in a rollover accident, fewer vertical supports must

carry a larger load. The Safety Board concludes that because the increased size of

passenger windows in motorcoaches may affect roof strength, rollover strength standards

must be developed to take into account the effect of typical window dimensions.

Therefore, the Safety Board believes that in 2 years, NHTSA should develop performance

standards for motorcoach roof strength that provide maximum survival space for all

seating positions and that take into account current typical motorcoach window

dimensions. The Safety Board also believes that once performance standards have been

developed for motorcoach roof strength, NHTSA should require newly manufactured

motorcoaches to meet those standards.
56 Special Investigation Report

Bus Classification and Data Collection

The vehicle definitions within the National Highway Traffic Safety

Administration’s (NHTSA’s) Federal Motor Vehicle Safety Standards (FMVSS)60 are

important because the applicability of safety standards relating to occupant crash

protection is based on these definitions. Vehicle classification within Federal accident

databases is important because public policy on vehicle safety is based, in part, on the

analysis of these databases, especially NHTSA’s Fatality Analysis Reporting System

(FARS).61 NHTSA does not have separate definitions for different bus body types in the

FMVSS other than to define them as either a bus or a school bus. In contrast, NHTSA uses

five body type classifications in FARS for buses: intercity/cross country bus, school bus,

transit bus, other bus, and unknown bus. This section discusses how these definitions and

classifications affect the collection, coding, and accuracy of bus accident data. It also

considers the role of on-board recorders in gathering accident data.

Bus Definitions in the FMVSS

The FMVSS define a bus as a motor vehicle with motive power, except a trailer,

designed for carrying more than 10 persons. They define a school bus as a bus sold or

introduced in interstate commerce for purposes that include carrying students to and from

school or school-related events. The definition does not include a bus designed and sold

for operation as a common carrier in urban transportation. A school bus is the only vehicle

in the FMVSS that is defined by use; all other motor vehicles are defined by body type. In

other words, according to the FMVSS, a bus is either a school bus or some other type of

bus that is not further defined.

The body types that are not further defined in the FMVSS include what are

commonly referred to in the industry as motorcoach/intercity buses and transit/urban

buses.62 Also included are what the Safety Board, in this special investigation, calls

specialty buses. Examples of specialty buses include those that retain their originally

manufactured cabs and chassis and that are later equipped with an after-market specially

manufactured passenger body, as well as those that appear similar to motorcoaches but

60 The purpose of the FMVSS is to a) reduce the risk of a vehicle crash by specifying minimum

performance levels for brakes, lights, and other components and to b) reduce the risk of injury, should a

crash occur, by specifying minimum requirements for vehicle performance in crashes, as related to occupant

protection, for occupant restraints, roof and body joint strength, fuel system integrity, child safety systems,

and other areas.

61 FARS was established in 1975 and contains data on fatal traffic crashes in the 50 States, the District of

Colombia, and Puerto Rico. To be included in FARS, a crash must involve a motor vehicle traveling on a

road open to the public and result in the death of a person within 30 days of the crash.

62 A transit bus as defined in this report is a vehicle that frequently loads and unloads passengers and

operates primarily in local, scheduled route service at lower-than-highway speeds. These buses are

manufactured with space and accommodations, such as support bars or straps to use as hand-holds, for

standing passengers.
Bus Classification and Data Collection 57 Special Investigation Report

have a lower chassis and no lower luggage compartment. In addition, vehicles that can

carry more than 10 passengers, which the public commonly refers to as vans, are built to

bus standards and thus are actually buses. (For examples of buses built to school bus

standards and of buses with undefined body types built to FMVSS bus standards, see

figures 24 and 25.)

The Federal Motor Carrier Safety Regulations (FMCSR)63 define a bus in two

ways: as any motor vehicle, including taxicabs, designed, constructed, or used for the

transportation of passengers (49 Code of Federal Regulations [CFR] 390.5) and as a

vehicle designed to carry more than 15 passengers, including the driver (49 CFR 393.5).

Thus, two Federal agencies (NHTSA and the Federal Highway Administration [FHWA])

in the U.S. Department of Transportation (DOT) have three different definitions of a bus

and also differ as to the minimum number of passenger seats in a motor vehicle defined as

a bus. With the exception of a school bus, the classifications used by NHTSA for the

FARS database are not consistent with any of these definitions. The Safety Board

therefore concludes that the DOT does not have standard definitions or classifications for

the various bus types. 

Data Collection

To determine the crashworthiness of motorcoaches and the magnitude of the

problem of occupant ejection, the Safety Board reviewed 40 bus accidents that it had

investigated between 1968 and 1997. (For further information on these accidents, see

appendix F.) Investigators examined these accidents in conjunction with FARS data to

identify the role of occupant ejection in fatalities and injuries in all fatal motorcoach

accidents. Of the 40 bus accidents reviewed, 27 had occurred since 1975, when FARS was

established, and the information from those 27 accidents was compared to that in the

FARS database. The purpose of this comparison was to obtain some indication of the

accuracy and completeness of the data in FARS and, therefore, its suitability for use in

determining the extent of occupant ejection in motorcoach accidents. Five accidents64

involving vehicles that were manufactured as school buses, but not operated as school

buses65 at the time of the accident, were also selected for comparison.

In 1993, in addition to the five body type classifications for buses in the FARS

database, NHTSA made provisions for identifying van-based school buses and transit

buses. Based on FARS classifications, the appropriate body type for all the motorcoach

accidents selected should have been intercity/cross country bus. Nonetheless, investigators

requested data for all five body types because specific Safety Board accidents could not be

located in FARS by this body type using the available definition or coding instructions.

63 The Federal Motor Carrier Safety Regulations, administered by the FHWA, apply to commercial

motor vehicles in interstate commerce. 64 Crashes involving school bus-type vehicles occurring at or near Tifton, Georgia, April 11, 1987,

NTSB No. HAR-79/02; Devers, Texas, December 23, 1983, NTSB No. HAR-84/06; Wofford Heights,

California, July 7, 1984, NTSB No. HAR-85/01; Carrollton, Kentucky, May 14, 1988, NTSB No. HAR89/01; and Palm Springs, California, July 31, 1991, NTSB No. HAR-93/01.

65 As defined by NHTSA in the FMVSS.
Bus Classification and Data Collection 58 Special Investigation Report

 Figure 24. Vehicles built to school bus standards (coded in FARS as school buses)
Bus Classification and Data Collection 59 Special Investigation Report

 Figure 25. Vehicles built to bus FMVSS

Bus Coded in FARS as Unknown or Other

Bus Coded in FARS as a Van-Based Bus
Bus Classification and Data Collection 60 Special Investigation Report

 Figure 25. Vehicles built to bus FMVSS

Bus Coded in FARS as a Motorcoach/Intercity Bus

Bus Coded in FARS as Unknown or Other
Bus Classification and Data Collection 61 Special Investigation Report

For example, the GMC motorcoach occupied by a church group in the Eureka

Springs, Arkansas, accident (NTSB No. HAR-87/01/SUM) was coded as a school bus,

and three of the five school bus body types were classified as other bus.

66 Discrepancies

were also noted in the classification of ejected passengers who were fatally injured. For

instance, the Safety Board investigated an accident involving a motorcoach that occurred

near Vernon, New Jersey, and resulted in six fatalities of passengers who were ejected

(NTSB/HAR-93/02). For this accident, FARS coded the body type of the motorcoach as

unknown and the six fatalities as unknown if ejected.

Table 9 presents the results of a comparison of Safety Board and FARS reporting

on fatalities and fatal ejections by body type. For the 32 accidents shown in this table, the

Safety Board and FARS reported different numbers of accidents for each body type. In

addition, FARS identified 14 fewer fatal ejections for all body types combined than the

Safety Board. In the motorcoach category, FARS identified 34 fewer fatal occupant

ejections than the Safety Board. Given such discrepancies in data, the Safety Board

concludes that FARS is not a reliable source for identifying the number of fatal occupant

ejections in motorcoaches. 

The Safety Board is also concerned that data may be incomplete for the other bus

classifications. For example, the FMVSS classify a 15-passenger van as a bus, but FARS

places it in the van-based light trucks category. Thus, NHTSA’s FMVSS and its FARS are

not consistent in identifying a bus. The varying body styles of specialty buses further

contribute to difficulties in accurate bus classifications.

During the Safety Board’s Bus Crashworthiness Public Hearing, a representative

from NHTSA stated that the agency is concerned about the classification of buses under

FARS, which the representative attributed to the variety of bus types used in the United

States. He specifically referred to the classification of “chopped” vans and the

approximately 20 percent of buses categorized as unknown bus. NHTSA reported that it is

working with the bus industry to develop a better classification system for buses that will

incorporate the classification into the vehicle identification number (VIN). NHTSA has

66 School bus body types involved in the Devers, Wofford Heights, and Palm Springs accidents.

Table 9. Fatalities/fatal occupant ejection by body type

Body Type No. Accidents Fatalities Fatal Ejection

Safety Board FARS Safety Board FARS Safety Board FARS

Motorcoach 24 12 134 46 54 20

School Bus 5 3 45 34 8 5

Transit Bus 1 3 1 19 0 2

Other Bus 2 11 7 82 1 20

Unknown Bus 0 3 0 602

Total 32 32 187 187 63 49
Bus Classification and Data Collection 62 Special Investigation Report

the authority to specify a character and incorporate it into the VIN, but according to the

NHTSA representative, modifications would take years. Therefore, NHTSA prefers that

the manufacturers voluntarily incorporate the change to the VIN. 

Safety Board staff met with NHTSA representatives to discuss their concerns

about the Safety Board’s findings. NHTSA acknowledged that bus classification data in

FARS are incomplete, noting that source documents used to code FARS data do not

provide specific details about the bus body type. According to NHTSA, the agency is

working with the manufacturers to identify bus make, model, and body type, using the

VIN, particularly buses that have previously been coded as either unknown or other bus.

NHTSA is also expanding the special use category to identify how a bus is being used. For

instance, if a motorcoach is used to transport pupils for a school function, it will be coded

as an intercity bus with special use as a school bus.

The Safety Board concludes that the incorporation of bus identification into the

VIN and the expansion of the use category will correct some of the inaccuracies in FARS

data, but without standard definitions and accurate classification of buses within FARS,

incomplete data and inaccuracies will still exist. 

Therefore, the Safety Board believes that in 1 year and in cooperation with the bus

manufacturers, the DOT should complete the development of standard definitions and

classifications for each of the different bus body types, and include these definitions and

classifications in the FMVSS. 

NHTSA also indicated that source data collected by the States may be incomplete

due to a lack of specificity on accident reporting forms and in vehicle registration files.

For example, Alabama’s accident reporting form defined a bus as “a motor vehicle

providing seats for 16 or more persons including the driver and used primarily for the

transportation of persons.” New Mexico’s form defines bus as a vehicle that has seats for

more than 15 people (including the driver). 

The Model Minimum Uniform Crash Criteria (MMUCC) were developed in 1998

with the cooperation of NHTSA, the FHWA, and the National Association of Governors’

Highway Safety Representatives (NAGHSR). They developed the model in an attempt to

address the disparate accident data being collected by the States and to provide requested

Federal guidance to States that were revising their accident data reporting forms. One

purpose of the model was to ensure that the States were collecting at least the minimum

amount of information needed for FARS.

The MMUCC’s definition of a bus, however, is different from other Federal

definitions. The MMUCC’s data collection requirement for an accident involving a bus

includes an indication of whether the accident was school bus-related and whether the

vehicle configuration was one of two bus types, that is, either a bus with seats for more

than 15 people, including the driver, or a bus with seats for 7 to 15 people, including the

driver. If States are being advised that these are the only bus data that need to be collected,

then NHTSA may have difficulty accurately identifying the bus body type of an accident

vehicle for use in the FARS database. The Safety Board concludes that the MMUCC do
Bus Classification and Data Collection 63 Special Investigation Report

not provide specific enough guidance to the States on bus body type coding. Therefore,

the Safety Board believes that once the standard definitions and classifications for each of

the different bus types have been established in the FMVSS, the DOT, in cooperation with

the NAGHSR, should amend the MMUCC’s bus configuration coding to incorporate the

FMVSS definitions and standards.

School Bus Occupant Injury Data

The accuracy of school bus injury data has been debated by the pupil

transportation community. According to testimony from a NHTSA representative at the

Safety Board’s August 1998 public hearing on bus crashworthiness, the agency believes

that the General Estimates System (GES)67 is reliable for estimating injuries in passenger

cars but that bus classification in the system is inaccurate. He also stated that NHTSA is

focusing on this problem and believes that additional information on bus passenger

injuries, such as injury levels, needs to be collected. 

The National Safety Council (NSC)68 recently announced that it will no longer

estimate the number of school bus injuries during the year. An NSC representative

informed Safety Board staff that injury estimates derived from information collected by

the States are no longer possible. Problems arose because the States collect information in

a nonstandard form,69 and some States do not report at all. In addition, the policy in many

school districts is to have all passengers automatically taken to the hospital when involved

in an accident, regardless of whether they are injured. Consequently, some passengers are

counted as injured, even when they go to the hospital only as a precaution. This policy, as

well as the level of injury, should be considered when collecting and analyzing the data.

The Safety Board concludes that school bus accident injury data are incomplete,

and, therefore, injuries cannot be reliably estimated. The Safety Board believes that

NHTSA should modify its methodology to collect accurate, timely, and sufficient data on

passenger injuries resulting from school bus accidents so that thorough assessments can be

made relating to school bus safety. 

On-Board Recording Devices

On-board recording devices represent an available technology that could be

implemented to facilitate bus classification and data collection. On-board devices that

record accident data, including crash pulses and other vehicle parameters, are now being

used on highway vehicles in Europe. This recording technology has recently been

introduced in the U.S. market and offers an effective means for NHTSA to gather crash

67 Data for the GES come from a nationally representative sample of police-reported vehicle crashes of

all types, from minor to fatal. NHTSA, using the GES, estimates that between 1988 and 1996, passengers in

school bus accidents sustained approximately 8,500 injuries annually.

68 The NSC is a not-for-profit public service organization that was chartered by an act of Congress to

educate and influence society on matters of safety. 69 The NSC’s Accident Facts, an annual report, states that variations exist among the States in several

areas, including operations, definitions of terms, and lack of comparable reporting.
Bus Classification and Data Collection 64 Special Investigation Report

pulse data on school buses and motorcoaches. By the end of 1999, an estimated 200

accident recorders will be installed on commercial vehicles in the United States.

Although devices that record accident data have only recently been introduced to

the U.S. market, recording systems that provide fleet management information have been

in use for several years. These systems often record minimal data such as vehicle speed

exceedances and are used primarily for driver monitoring and training. Although capable

of providing limited data for accident investigations, these recorders do not record the

quantitative data necessary for a thorough and accurate reconstruction of an accident

sequence. Secondary recording devices, such as engine control modules, have also

provided data to investigations, but their value to investigations is also limited by the

minimal information recorded and the format of the recorded information.

Off-the-shelf on-board vehicle recording systems have been in use in Europe for

several years. These recorders have not only provided needed crash data and assisted in

accident investigations, but have also helped to reduce accidents for vehicles equipped

with recorders. For instance, in 1996, all 62 patrol cars of a Berlin, Germany, police office

were equipped with accident data recorders. Subsequently, these vehicles experienced a

20-percent reduction in driver-related accidents and a 36-percent reduction in the number

of accidents that occurred during emergency trips. As a result, the Berlin police authority

equipped its entire fleet of more than 400 patrol cars with accident data recorders.70

Another study, published in 1995, which was conducted as part of the EU’s safety

assessment monitoring of vehicles with automatic recording devices, involved equipping

9 vehicle fleets, or 341 vehicles, in Great Britain, the Netherlands, and Belgium with

accident data recorders. The 1-year program also included a control group, for a total of

850 vehicles. At year’s end, the accident rate had decreased by 28.1 percent for those

vehicles equipped with recorders, as compared with the control group. Accident data

recorders have also been used on buses in other countries. During a trial period in

Germany, where 123 buses in the Baden-Württemberg bus fleet were equipped with

recorders, the number of accidents in that fleet decreased between 15 and 20 percent

(depending on the company concerned), as compared to the reference period.71

On-board recorders have been used on highway vehicles for fleet management and

operator oversight for several years in the U.S. In addition, recording formats such as

tachographs that automatically record driver operational information on paper, have been

in use for over two decades. For example, the Police Department of Metropolitan

Nashville and Davidson County, Tennessee, has been using tachographs on its vehicles for

approximately 20 years. Not only has it been a vital management tool, but the initial study

performed for the police department showed that accident rates had dropped. The accident

70 Lehmann, Gerhard, and Reynolds, Tony, “The Contribution of On-board Recording Systems to Road

Safety and Accident Analysis,” Transportation Recording: 2000 and Beyond, Proceedings, International

Symposium on Transportation Recorders, May 3-5, 1999, Arlington, Virginia (Washington, DC: National

Transportation Safety Board, and The Hague, Netherlands: International Transportation Safety Association)

243-5. 

71 Lehmann and Reynolds, 243-5.
Bus Classification and Data Collection 65 Special Investigation Report

rate for the Traffic Section dropped from 1.3 to 0.6 accidents per 100,00 miles, while the

accident rate for personal injury accidents in the Patrol Section experienced a 55-percent

reduction to 0.25 accidents per 100,000 miles.72

On-board recorders have been commonly used as many as 6 years by more than

100 U.S. jurisdictions to manage their school bus fleets. The jurisdictions using fleet

management or trip recorders include Montgomery County, Maryland; Washington

County, Maryland; Los Angeles, California; Cherryvalley-Springfield, New York;

Dryden, New York; Guilderland, New York; and Newark, New York. As was discussed

earlier in this section, European and U.S. studies have found the use of both accident and

fleet management recorders has had a positive impact on operational safety for other types

of vehicle fleets. A study73 commissioned by Laidlaw, Inc.,74 found safety benefits for

school bus fleets as well. Prompted by the comparatively high accident rate in a school bus

fleet in Bridgeport, Connecticut, the Laidlaw study examined the effect on safety

following installation of fleet management on-board recorders. The study, which took

place from December 1, 1996, to May 30, 1997, consisted of fitting 65 of the 150 school

buses in the Bridgeport fleet with fleet management recorders. During the study, driver

speeding was monitored, and those drivers who spent over 25 percent of their trip miles at

speeds over a set threshold were required to participate in counseling sessions. At the end

of the trial period, those buses not equipped with on-board recording systems accounted

for 72 percent of the fleet’s accidents.75 In light of these results, Laidlaw installed onboard fleet management recorders in the remainder of the Bridgeport fleet. After a year,

officials were able to identify a contributing factor to the high accident rate that related to

driver training. Laidlaw subsequently evaluated and accordingly modified its training

program. 

Although the fleet management recorders used in this study and in other U.S.

school bus fleets do not provide data such as crash pulses, the combination of fleet

management information and limited data, such as speed, made improvements in safety

possible for Laidlaw’s Bridgeport fleet. Further, the presence of on-board recorders for

fleet management in more than 100 school bus fleets shows that many jurisdictions are

already taking advantage of the tools that on-board recorder systems can provide. Because

of the safety improvements that have occurred as a result of using on-board recorders,

both for accident data and fleet management, the Safety Board concludes that the use of

on-board recorders may help reduce the accident rates of vehicle fleets. 

On-board recorders can also provide important crash pulse data and other vehicle

information during frontal impacts, side impacts, rollovers, and other dynamic vehicle

events. To date, much of the debate regarding bus occupant protection has been fueled by

the lack of available crash pulse data. On-board recorders constitute the most thorough

method of obtaining bus accident data; moreover, the collection of crash data will be

72 Gill, Captain Paul J., and Larson, Lynn D., A Report on the Use of Tachographs in Marked Police

Vehicles, Police Department of Metropolitan Nashville and Davidson County, Tennessee, 1979. 73 Final Report for Bridgeport, CT Facility, ARGO Fleet Systems, VDO North America LLC, June 12, 1997. 74 Laidlaw, Inc., is the largest contract operator of school bus fleets in the United States.

75 ARGO Fleet Systems Bridgeport report, 1997.
Bus Classification and Data Collection 66 Special Investigation Report

necessary for the continuing development of bus occupant protection systems. Because of

these factors, the Safety Board concludes that on-board recorders are needed to provide

quantitative data to evaluate the dynamics of bus crashes. The Safety Board is of the

opinion that to enhance the accuracy of school bus and motorcoach investigations,

parameters in addition to crash pulse or acceleration data, such as vehicle speed, engine

speed, heading, and the status of different lights and vehicle systems, are needed. Further,

the parameters should be recorded at a sampling rate that is sufficient to define vehicle

dynamics. In addition, the resulting data should be preserved in the event of a vehicle

crash or an electrical power loss. The Safety Board therefore believes that NHTSA should

require that all school buses and motorcoaches manufactured after January 1, 2003, be

equipped with on-board recording systems that record vehicle parameters, including, at a

minimum, lateral acceleration, longitudinal acceleration, vertical acceleration, heading,

vehicle speed, engine speed, driver’s seat belt status, braking input, steering input, gear

selection, turn signal status (left/right), brake light status (on/off), head/tail light status

(on/off), passenger door status (open/closed), emergency door status (open/closed), hazard

light status (on/off), brake system status (normal/warning), and flashing red light status

(on/off) (school buses only). For those buses so equipped, the following should also be

recorded: status of additional seat belts, airbag deployment criteria, airbag deployment

time, and airbag deployment energy. The on-board recording system should record data at

a sampling rate that is sufficient to define vehicle dynamics and should be capable of

preserving data in the event of a vehicle crash or an electrical power loss. In addition, the

on-board recording system should be mounted to the bus body, not the chassis, to ensure

that the data necessary for defining bus body motion are recorded. 

Through years of experience with on-board recording devices in the aviation, rail,

and marine modes of transportation, the Safety Board and the transportation industry have

learned a great deal about the effective introduction of recording technology. Establishing

industry standards for recording in these modes has been critical to effective

implementation of on-board recorders. Industry standards ensure consistency in recorded

data and prevent the proliferation of multiple formats and configurations. They also foster

the efficient introduction of new recording system technology. 

The factors identified in developing on-board recording standards for other modes

of transportation provide a basis for formulating highway recording standards. Parameters

to be recorded, data sampling rates, duration of recording, interface configurations, and

data storage format all need to be considered. Other factors include survivability issues,

such as fluid immersion, impact shock, crush penetration, and fire. Following recent

advances in technology, independent power supplies are being introduced into the onboard recorder industry. Use of an independent power supply helps prevent the loss of

recorded data when main vehicle power ceases and results in loss of power to the recorder.

An additional factor to be considered is the incorporation of fleet management tools

discussed above. Finally, a critical factor in the development of effective recording

standards is the ability to accommodate future requirements and technological advances.

Applying the knowledge gained during implementation of on-board recorders in

other transportation modes is an important step to the effective implementation and use of
Bus Classification and Data Collection 67 Special Investigation Report

on-board recorders on highway vehicles. The benefits of industry standards for on-board

recorders in other modes of transportation demonstrate the need for similar standards in

the highway industry. The Safety Board concludes that establishing on-board recording

standards for highway vehicles will provide a necessary foundation for the future use of

on-board recorders. The Safety Board believes that NHTSA should develop and

implement, in cooperation with other Government agencies and industry, standards for onboard recording of bus crash data that address, at a minimum, parameters to be recorded,

data sampling rates, duration of recording, interface configurations, data storage format,

incorporation of fleet management tools, fluid immersion survivability, impact shock

survivability, crush and penetration survivability, fire survivability, independent power

supply, and ability to accommodate future requirements and technological advances.
68 Special Investigation Report

Conclusions

1. In the accidents analyzed for this special investigation, school bus passengers who

remained within the seating compartment but not within the intrusion area during the

accident sequence were less likely to have been seriously injured than passengers

who were out of the compartment before the collision or who were propelled from

the compartment during the collision.

2. Because of compartmentalization, school bus passengers are safer now than they

were before 1977. 

3. Current compartmentalization is incomplete in that it does not protect school bus

passengers during lateral impacts with vehicles of large mass and in rollovers,

because in such accidents, passengers do not always remain completely within the

seating compartment. 

4. All potential designs for occupant protection systems to be used on school buses

should be tested to uniform performance standards developed by the National

Highway Traffic Safety Administration to ensure occupant safety. 

5. It cannot be determined whether the current design of available restraint systems for

large school buses would have reduced the risk of injury to the school bus passengers

in the accidents analyzed for this special investigation.

6. The potential exists for an occupant crash protection system to be developed that

would protect school bus passengers in most accident scenarios.

7. One of the primary causes of preventable injury in motorcoach accidents involving a

rollover, ejection, or both is occupant motion out of the seat during a collision when

no intrusion occurs into the seating area. 

8. The overall injury risk to occupants in motorcoach accidents involving rollover and

ejection may be reduced significantly by retaining the occupant in the seating

compartment throughout the collision. 

9. New occupant crash protection systems for motorcoaches should be tested to uniform

performance standards developed by the National Highway Traffic Safety

Administration that are based upon actual crash testing of motorcoaches to ensure

occupant safety. 

10. Equipping motorcoach side windows with advanced glazing may decrease the

number of ejections of unrestrained passengers during motorcoach accidents and

decrease the risk of serious injuries to restrained passengers during motorcoach

accidents. 
Conclusions 69 Special Investigation Report

11. Because the increased size of passenger windows in motorcoaches may affect roof

strength, rollover strength standards must be developed to take into account the effect

of typical window dimensions. 

12. The U.S. Department of Transportation does not have standard definitions or

classifications for the various bus types. 

13. The Fatality Analysis Reporting System (FARS) is not a reliable source for

identifying the number of fatal occupant ejections in motorcoaches. 

14. The incorporation of bus identification into the vehicle identification number and the

expansion of the use category will correct some of the inaccuracies in FARS data, but

without standard definitions and accurate classification of buses within FARS,

incomplete data and inaccuracies will still exist. 

15. The Model Minimum Uniform Crash Criteria do not provide specific enough

guidance to the States on bus body type coding. 

16. School bus accident injury data are incomplete, and, therefore, injuries cannot be

reliably estimated. 

17. The use of on-board recorders may help reduce the accident rates of vehicle fleets.

18. On-board recorders are needed to provide quantitative data to evaluate the dynamics

of bus crashes.

19. Establishing on-board recording standards for highway vehicles will provide a

necessary foundation for the future use of on-board recorders. 
70 Special Investigation Report

Recommendations

To the U.S. Department of Transportation:

In 1 year and in cooperation with the bus manufacturers, complete the

development of standard definitions and classifications for each of the

different bus body types, and include these definitions and classifications

in the Federal Motor Vehicle Safety Standards. (H-99-43)

Once the standard definitions and classifications for each of the different

bus types have been established in the Federal Motor Vehicle Safety

Standards, in cooperation with the National Association of Governors’

Highway Safety Representatives, amend the Model Minimum Uniform

Crash Criteria’s bus configuration coding to incorporate the FMVSS

definitions and standards. (H-99-44)

To the National Highway Traffic Safety Administration:

In 2 years, develop performance standards for school bus occupant

protection systems that account for frontal impact collisions, side impact

collisions, rear impact collisions, and rollovers. (H-99-45)

Once pertinent standards have been developed for school bus occupant

protection systems, require newly manufactured school buses to have an

occupant crash protection system that meets the newly developed

performance standards and retains passengers, including those in child

safety restraint systems, within the seating compartment throughout the

accident sequence for all accident scenarios. (H-99-46)

In 2 years, develop performance standards for motorcoach occupant

protection systems that account for frontal impact collisions, side impact

collisions, rear impact collisions, and rollovers. (H-99-47)

Once pertinent standards have been developed for motorcoach occupant

protection systems, require newly manufactured motorcoaches to have an

occupant crash protection system that meets the newly developed

performance standards and retains passengers, including those in child

safety restraint systems, within the seating compartment throughout the

accident sequence for all accident scenarios. (H-99-48)

Expand your research on current advanced glazing to include its

applicability to motorcoach occupant ejection prevention, and revise

window glazing requirements for newly manufactured motorcoaches based

on the results of this research. (H-99-49)
Recommendations 71 Special Investigation Report

In 2 years, develop performance standards for motorcoach roof strength

that provide maximum survival space for all seating positions and that take

into account current typical motorcoach window dimensions. (H-99-50)

Once performance standards have been developed for motorcoach roof

strength, require newly manufactured motorcoaches to meet those

standards. (H-99-51)

Modify your methodology to collect accurate, timely, and sufficient data on

passenger injuries resulting from school bus accidents so that thorough

assessments can be made relating to school bus safety. (H-99-52)

Require that all school buses and motorcoaches manufactured after January

1, 2003, be equipped with on-board recording systems that record vehicle

parameters, including, at a minimum, lateral acceleration, longitudinal

acceleration, vertical acceleration, heading, vehicle speed, engine speed,

driver’s seat belt status, braking input, steering input, gear selection, turn

signal status (left/right), brake light status (on/off), head/tail light status

(on/off), passenger door status (open/closed), emergency door status

(open/closed), hazard light status (on/off), brake system status

(normal/warning), and flashing red light status (on/off) (school buses only).

For those buses so equipped, the following should also be recorded: status

of additional seat belts, airbag deployment criteria, airbag deployment

time, and airbag deployment energy. The on-board recording system

should record data at a sampling rate that is sufficient to define vehicle

dynamics and should be capable of preserving data in the event of a vehicle

crash or an electrical power loss. In addition, the on-board recording

system should be mounted to the bus body, not the chassis, to ensure that

the data necessary for defining bus body motion are recorded. (H-99-53)

Develop and implement, in cooperation with other Government agencies

and industry, standards for on-board recording of bus crash data that

address, at a minimum, parameters to be recorded, data sampling rates,

duration of recording, interface configurations, data storage format,

incorporation of fleet management tools, fluid immersion survivability,

impact shock survivability, crush and penetration survivability, fire

survivability, independent power supply, and ability to accommodate future

requirements and technological advances. (H-99-54)

To the National Association of Governors’ Highway Safety Representatives:

In conjunction with the U.S. Department of Transportation, amend the

Model Minimum Uniform Crash Criteria’s bus configuration coding to

comply with standard definitions and classifications of buses. (H-99-55)
Recommendations 72 Special Investigation Report

To the bus manufacturers:

Cooperate with the U.S. Department of Transportation in the development

of standard definitions and classifications for each of the different bus body

types. (H-99-56)

BY THE NATIONAL TRANSPORTATION SAFETY BOARD

JAMES E. HALL

Chairman

JOHN A. HAMMERSCHMIDT

Member

ROBERT T. FRANCIS II

Vice Chairman

JOHN J. GOGLIA

Member

GEORGE W. BLACK, JR.

Member

Adopted: September 21, 1999
73 Special Investigation Report

Appendix A

Public Hearing Agenda
74 Special Investigation Report

Appendix B

Federal Motor Vehicle Safety Standards for Buses1

Federal Motor Vehicle Safety Standards Affecting Buses (Precrash)

Small Bus 

Onlya

a. Includes small school buses (GVWR ≤ 10,000 pounds).

School Bus 

Onlyb

b. Includes both large and small school buses.

Number Standard

101 Control Location, Identification, and Illumination

102 Transmission Shift Lever Sequence

103 Windshield Defrosting and Defogging

104 Windshield Wiping and Washing System

105 Hydraulic Brake Systems

106 Brake Hoses

108 Lamps, Reflective Devices, and Equipment

111 Rearview Mirrors

113 Hood Latches

116 Motor Vehicle Brake Fluids

119 New Pneumatic Tires

120 Tire Selection and Rims

121 Air Brake Systems

124 Accelerator Control Systems

✓ 131 School Bus Pedestrian Safety Devices

1 All FMVSS are from 49 CFR Part 571.
Appendix B 75 Special Investigation Report

Federal Motor Vehicle Safety Standards Affecting Buses (Crash and Postcrash)

Small Bus

Onlya

School Bus 

Onlyb Number Standard

✓ 201 Occupant Protection in Interior Impact

✓ 202 Head Restraints

✓ 203 Impact Protection for the Driver

✓ 204 Steering Control Rearward Displacement

205 Glazing Materials

207 Seating Systems (Driver)

208 Occupant Crash Protection (Driver)

209 Seat Belt Assemblies

210 Seat Belt Assembly Anchorages

✓ 212 Windshield Mounting

✓ 214 Side Impact Protection

217 Bus Emergency Exits and Window Retention and Release

✓ 219 Windshield Zone Intrusion

✓ 220 School Bus Rollover Protection

✓ 221 School Bus Body Joint Strength

✓ 222 School Bus Passenger Seating and Crash Protection

✓ 301 Fuel System Integrity

302 Flammability of Interior Materials

✓ 303 Fuel System Integrity of Compressed NG Vehicles

304 Compressed Natural Gas Fuel Container Integrity

a. Includes small school buses (GVWR ≤ 10,000 pounds).

b. Includes large and small school buses.
Appendix B 76 Special Investigation Report

Federal Motor Vehicle Safety Standards Applicable to School Busesa

GVWR 10,000 lb. GVWR > 10,000 lb.

Occupant Protection 

Standards

201, 202, 203, 204, 205, 207, 208, 

209, 210, 212, 214, 217, 219, 220, 

221, 222

205, 207, 208, 209, 210, 217, 220, 

221, 222

Precrash Standards 101, 102, 103, 104, 105, 106, 108, 

111, 113, 116, 119, 120, 121, 124, 

131

101, 102, 103, 104, 105, 106, 108, 

111, 113, 116, 119, 120, 121, 124, 

131

Postcrash Standards 301, 302, 303, 304 301, 302, 303, 304

a. Standards 212, 214, 219, 301, and 303 are dynamically tested. 

Occupant Protection Requirements for Buses

Seating Position Side Impact

Fuel System 

Integrity

Driver Passenger Dynamic

Bus 8,500 lb. Lap/Shoulder 

Belt

Lap/Shoulder 

and Lap belta ✓✓ ✓

Bus 8,500–10,000 lb. Lap/Shoulder 

Belt

Lap/Shoulder 

and Lap Beltb ✓ ✓

Bus > 10,000 lb. Lap Belt

School Bus 

 10,000 lb.

Lap/Shoulder 

Belt

FMVSS 222 

Lap Belt ✓ ✓

School Bus 

> 10,000 lb.

Lap Belt FMVSS 222 ✓

a. Lap/shoulder belts are located at outboard positions; lap belts only are located at the center positions.

b. Restraints the same as those under 8,500 lb.

≤

≤

≤
Appendix B 77 Special Investigation Report

Summaries of Crash and Postcrash Standards

FMVSS 201 Occupant Protection in Interior Impact—This standard specifies requirements to

afford impact protection for occupants. It applies to passenger cars and to multipurpose vehicles, trucks, and

buses with a GVWR of 4,536 kilograms or less, except that the requirements for upper interior components

do not apply to buses with a GVWR of 3, 860 kilograms.

FMVSS 202 Head Restraints—This standard specifies requirements for head restraints to reduce

the frequency and severity of neck injury in rear-end and other collisions. This standard applies to passenger

cars, and to multipurpose passenger vehicles, trucks, and buses with a GVWR of 10,000 or less. For school

buses, this standard only applies to the driver’s seating position.

FMVSS 203 Impact Protection for the Driver—This standard specifies requirements for steering

control systems that will minimize chest, neck, and facial injuries to the driver as a result of impact. This

standard applies to passenger cars and to multipurpose passenger vehicles, trucks, and buses with a GVWR

of 10,000 pounds or less. However, it does not apply to vehicle that conform to the frontal barrier crash

requirements of FMVSS 208 by means of other than seat belt assemblies. It also does not apply to walk-in

vans.

FMVSS 204 Steering Control Rearward Displacement—This standard specifies requirements

limiting the rearward displacement of the steering control into the passenger compartment to reduce the

likelihood of chest, neck, or head injury. This standard applies to passenger cars and to multipurpose

passenger vehicles, trucks, and buses. However, it does not apply to walk-in vans. 

FMVSS 205 Glazing Materials—The purpose of this standard is to reduce injuries resulting from

impact to glazing surfaces, to ensure a necessary degree of transparency in motor vehicle windows for driver

visibility, and to minimize the possibility of occupants being thrown through the vehicle windows in

collisions. This standard applies to glazing materials for use in passenger cars, multipurpose vehicles, trucks,

buses, motorcycles, slide-in campers, and pickup covers designed to carry persons while in motion.

FMVSS 207 Seating System—The purpose of this standard is to establish requirements for

vehicle seats, and their attachment and installation in order to minimize injury to occupants during a crash.

This standard applies to passenger cars, multi-purpose passenger vehicles, trucks, and buses. The

applicability of this safety standard for buses applies only to the driver seat position.

The seat must be able to withstand a force 20 times the weight of the seat, applied both forward and

rearward. Also, the seat must be able to withstand this force when the seat is adjusted to any position. If the

seat has seat belt assemblies attached directly to the seat, the seat must be able to withstand the additional

forces imposed by FMVSS 210 for seat belt anchorages simultaneous with the forces required for FMVSS

207. In addition, the seat must also be able to withstand a rotational moment of 3,300 inch-pounds with the

seat in the rearmost travel position.

FMVSS 208 Occupant Crash Protection—The purpose of this standard is to reduce the number

of vehicle occupant deaths and the severity of injuries by specifying vehicle crashworthiness requirements.

These requirements limit the forces and accelerations measured on anthropomorphic dummies in crash tests.

The standard also specifies equipment requirements for active (manual) and passive (automatic) restraint

systems.

This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. Buses

with a 10,000 pound GVWR or less are required to have a lap and shoulder belt at the driver’s position and

all outboard seating positions and a lap belt at all inboard seating positions. School buses with a 10,000

pound GVWR or less must have a lap and shoulder belt at the driver’s position and either a lap belt or a lap

shoulder belt at all rear passenger positions. This standard does not provide protection for bus occupants in

buses over 10,000 pounds GVWR.

For buses over 10,000 pounds GVWR the requirement of FMVSS 208 is met through the

installation of an FMVSS 209-approved seat belt assembly (or other automatic crash protection device) for

the driver seat position. The pelvic portion of such a belt assembly shall include either an emergency locking

retractor or an automatic locking retractor.

FMVSS 209 Seat belt Assemblies—The purpose of this standard is to specify requirements for all

seat belt assemblies in passenger cars, multipurpose passenger vehicles, trucks, and buses. 

The initial requirement is that a designated seat belt assembly is to be designed for use by one, and

only one, person at any one time. The seat belt shall provide pelvic and/or upper torso restraint. The

hardware and webbing shall be free from burrs and sharp edges. The seat belt assembly buckles shall be

readily accessible and easily released, while minimizing the possibility of inadvertent release. Each belt
Appendix B 78 Special Investigation Report

assembly shall be marked as to the manufacturing source and the date of manufacture. The belt assembly

webbing shall a minimum of 1.8 inches width, and have a minimum breaking strength of 6,000 pounds for a

lap belt only, 5,000 pounds for a lap belt used in conjunction with a shoulder belt, and 4,000 pounds for

shoulder belt used in conjunction with a lap belt. The elongation shall not exceed 20 percent at a 2,500

pound force for a lap belt used singularly, or 30 percent at 2,500 pounds for a lap belt and 40 percent at 2,500

pounds for a shoulder belt used in conjunction. The belt webbing shall not significantly degrade due to

exposure to sunlight, micro-organisms, or from abrasion. The belt hardware shall also be temperature and

corrosion resistant.

FMVSS 210 Seat belt Assembly Anchorages—The purpose of this standard is to establish

requirements for the seat belt assembly anchorages to ensure their proper location for effective occupant

restraint and establishes minimum strength requirement to reduce the likelihood of their failure.

This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. As the

seat belt installation requirement for buses over 10,000 pounds GVWR applies only to the driver seat

position this standard is not relevant to, or applicable for, passenger seat positions on buses. 

The seat belt anchorage point, either to the seat frame or floor of the vehicle, has various

dimensional requirements designed to provide suitable belt geometry to allow occupants to sustain crash

forces properly distributed to the skeletal portion of the body. For a manual lap or lap and shoulder belt,

these anchorage points must be able to withstand a pull of 5,000 pounds, applied between 5 and 15 degrees

from the horizontal. The tensile load must be applied in a period less than 30 seconds and be able to maintain

such a load for at least 10 seconds.

FMVSS 212 Windshield Mounting—This standard establishes windshield retention requirements

for motor vehicles during crashes. The purpose of this standard is to reduce crash injuries and fatalities by

providing for retention of the vehicle windshield during a crash, thereby utilizing fully the penetrationresistance and injury-avoidance properties of the windshield glazing material and preventing the ejection of

the occupants form the vehicle. This standard applies to passenger cars and to multipurpose passenger

vehicles, trucks, and buses having a GVWR of 4536 kilograms or less. However, it down not apply to

forward control vehicles, walk-in van-type vehicles, or to open-body type vehicles with fold-down or

removable windshields.

FMVSS 214 Side Impact Protection—This standard specifies performance requirements for

protection of occupants in side impact crashes. The purpose of this standard is to reduce the risk of serious

and fatal injury to occupants of passenger cars in side impact crashes by specifying vehicle crashworthiness

requirements in terms of accelerations measured on anthropomorphic dummies in test crashes, by specifying

strength requirements for side doors and by other means. This standard applies to passenger cars and

multipurpose passenger vehicles, trucks, and buses with a GVWR of 10,000 pounds or less, except for walkin vans.

FMVSS 216 Roof Crush Resistance—The purpose of this standard is to reduce injuries and

deaths due to crushing of the roof into the passenger compartment in rollover accidents.

This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses with a

GVWR of 6,000 pounds or less. This standard does not apply to convertible passenger cars, school buses, or

buses with a GVWR of 6,000 pounds or more.

A rigid, unyielding block test device, with a contact surface measuring 2.5 feet by 6 feet, is pressed

against the edge of the vehicle roof at a shallow angle. The block is loaded to provide a downward force of

1.5 times the unloaded weight of the vehicle. The crush of the roof shall not exceed 5 inches as measured by

the contact surface of the test device.

FMVSS 217 Bus Emergency Exits and Window Retention and Release—The purpose of this

standard is to minimize the likelihood of occupants being thrown from the bus and to provide a means of

readily accessible emergency egress. This standard establishes requirements for the retention of windows

other than windshields in buses and establishes operating forces, opening dimensions, and markings for bus

emergency exits.

FMVSS 219 Windshield Zone Intrusion—This standard specifies limits for the displacement into

the windshield area of motor vehicle components during a crash. The purpose of this standard is to reduce

crash injuries and fatalities that result from occupants contacting vehicle components displaced near or

through the windshield. This standard applies to passenger cars, multipurpose passenger vehicles, trucks,

and buses of 10,000 pounds or less GVWR. However, it does not apply to forward control vehicles, walk-in

van-type vehicles or to open-body-type vehicles with fold-down or removable windshields.

FMVSS 220 School Bus Rollover Protection—The purpose of this standard is to reduce the

number deaths and severity of injuries resulting from failure of the school bus body structure to withstand

forces encountered in rollover crashes. This standard applies to school buses. This standard does not apply to

other buses or to other vehicle categories.
Appendix B 79 Special Investigation Report

A force is applied to the roof of the bus. The force is applied through a rigid, unyielding rectangular

block test device called a force application plate. For buses with a GVWR of more than 10,000 pounds, the

plate measures 36 inches wide and is 12 inches shorter than the vehicle roof. The plate is pressed against the

roof of the bus with a force equal to 1.5 times the unloaded weight of the vehicle. With the force application

plate vertical movement not exceeding 5.125 inches, the bus windows shall be operable per the process

described in FMVSS 217.

FMVSS 221 School Bus Body Joint Strength—This standard establishes requirements for the

strength of the body panel joints in school bus bodies. This standard originally applied to school buses with

a GVWR exceeding 10,000 pounds. A recent final rule extends the requirement to all small school buses

manufactured on or after May 5, 2000. Each body panel joint, where the various body panels are connected,

must be able to withstand a load of at least 60 percent of the strength of the inherent body panel.

FMVSS 222 School Bus Passenger Seating and Crash Protection—This standard establishes

occupant protection requirements for school bus passenger seating and restraining barriers. The purpose of

this standard is to reduce the number of deaths and the severity of injuries that result from the impact of

school bus occupants against structures within the vehicle during crashes and sudden driving maneuvers.

This standard applies to school buses.

FMVSS 301 Fuel System Integrity—The purpose of this standard is to reduce deaths and injuries

from fires that result from fuel spillage during and after motor vehicle crashes and from ingestion of fuels

during siphoning. 

This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses with a

GVWR of 10,000 pounds or less and school buses with a GVWR greater than 10,000 pounds. The

applicable fuel for these vehicles shall have a boiling point above 32 degrees F.

School buses with a GVWR of more than 10,000 pounds are tested by being struck by a moving

barrier which approximates a 4,000-pound automobile. The bus test condition replicates a full load of fuel,

operational fuel pump, and normal load condition of 120 pounds per occupant seat position. The moving

barrier test device strikes the bus body at speeds up to and including 30 mph in a lateral and rear

configuration per test procedure in FMVSS 208. The bus body is then rolled in quarter turn sequences. Fuel

leakage must not exceed a rate of one ounce per minute.

FMVSS 302 Flammability of Interior Materials—This standard specifies burn resistance

requirements for materials used in the occupant compartment of motor vehicles. The purpose of this

standard is to reduce the deaths and injuries to motor vehicle occupants caused by vehicle fires, especially

those originating in the interior of the vehicle from sources such as matches and cigarettes. This standard

applies to passenger cars, multipurpose passenger vehicles, trucks, and buses.

FMVSS 303 Fuel System Integrity of Compressed Natural Gas Vehicles—This standard

specifies requirements for the integrity of motor vehicle fuel systems using compressed natural gas (CNG),

including the CNG fuel systems of bi-fuel, dedicated, and dual fuel CNG vehicles. The purpose of this

standard is to reduce deaths and injuries occurring from fires that result from fuel leakage during and after

motor vehicle crashes. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and

buses that have a GVWR of 10,000 pounds or less and use CNG as fuel. This standard also applies to school

buses regardless of weight that use CNG as motor fuel.

FMVSS 304 Compressed Natural Gas Fuel Container Integrity—This standard specifies

requirements for the integrity of compressed natural gas (CNG) motor vehicle fuel containers. The purpose

of this standard is to reduce deaths and injuries occurring from fires that result form fuel leakage during and

after motor vehicle crashes. This standard applies to containers designed to store CNG as motor fuel

on-board any vehicles.
80 Special Investigation Report

Appendix C

Accident Simulation Assumptions and Limitations

Assumptions

• Simulated occupants represent the physical dimensions of the passengers in the

actual accidents.

• The crash pulse developed is representative of actual crash dynamics.

• Critical injury values are accurate for children and young adults.

• Seat belts are well fitted and are in contact with the simulated occupant’s body

at the beginning of the accident.

• Simulated occupants are seated (except for the Holyoke accident) and forward

facing unless indicated otherwise by passengers or witnesses.

• Default contact surface material definitions are representative of actual

surfaces inside vehicle (such as seats, windows, windshields, walls, and doors).

• Seatbacks are not stiffened to reflect the additional load of a lap/shoulder belt.

Limitations

• Simulations cannot predict fatalities, only the probability of sustaining a head,

neck, or chest injury. 

• Simulations cannot provide an exact reconstruction of the actual accident, as

they are limited by the inputs to the model. (However, simulations are

representative of the accident.)

• Neck injuries are assessed only for flexion/extension injuries using Graphical

Articulated Total Body (GATB). The MAthematical DYnamical MOdel

(MADYMO) simulations only investigated neck injuries, using the National

Highway Traffic Safety Administration’s neck injury criteria, for the belted

simulated occupants. Neck injuries for the unrestrained simulated occupants

were not investigated because the simulated dummy that would predict neck

injuries had not been developed when the simulations were conducted for this

special investigation.

• Chest deflections are not measured with either MADYMO or the GATB, and

thus may affect the accuracy of the chest acceleration values.

• Intrusion into the passenger compartment is not simulated with the Human

Vehicle Environment (HVE) system, and consequently, it is not simulated with

MADYMO.
Appendix C 81 Special Investigation Report

• Accelerations are placed at the center of gravity of the vehicle, and, therefore,

the higher accelerations at a point of intrusion or damage are not simulated for

the occupant models.

• Head injury criteria is a measure of translational accelerations, not of angular

accelerations. 

• Active responses, such as whether a passenger was aware of the impending

accident and braced, are unknown and therefore are not simulated.

• Finite element seat belts are not available with the GATB simulation in the

HVE system. (They are available with the MADYMO simulation.)

• Elliptical contact surfaces to construct the seats are not available with the

GATB simulation in the HVE system. (They are available with the MADYMO

simulation.) 
82 Special Investigation Report

Appendix D

International Perspectives

The European Union

Initially, the organization of sovereign member states now known as the European

Union (EU) was known as the European Economic Community, or the European

Community. The Treaty of Rome established this organization, which now includes 15

member states,1 in 1958 for the purpose of fostering free trade among its members. Initial

legislation was aimed at facilitating the freer movement of goods and services within the

EU. The EU has now expanded its activities to include creating uniform social and

economic trade legislation.

The European Commission (Commission) is the administrative branch of the EU.

The Commission’s role is to ensure that existing legislation is applied correctly and to

propose legislation. Since the EU has expanded its activities to include not only economic

but also social legislation, the scope of the Commission’s responsibilities has increased.

The Commission now has considerable powers to propose legislation that addresses safety

issues, particularly the issue of road safety.

The Commission itself is a nonelected body of 20 commissioners appointed by the

member states for 5-year terms. Large countries (the United Kingdom, Germany, France,

Italy, and Spain) have two commissioners each. Each other country has one commissioner.

There are 24 directorates general within the Commission, each headed by one of the 20

commissioners (several of the commissioners oversee more than one directorate). A

Director General who is the permanent administrative head of the Commission heads the

European Commission.

The EU promulgates two types of legislation: regulations and directives. A

directive is framework legislation; a regulation is rigid. For example, if a directive says

that the maximum length of a motor vehicle in the EU is 12 meters (39.4 feet), each

member state can interpret the rule as it wishes In this example, a member state can choose

to have a maximum length of 11.5 meters (37.7 feet) with a positive tolerance of 0.5

meters (1.64 feet).

A regulation is rigid: its wording must be followed exactly. Member states cannot

interpret or modify the requirement. The requirement that a tachograph be fitted on buses,

motorcoaches, and trucks operated in the EU is an example of a regulation. The type of

tachograph and its required functions are specifically detailed. 

Generally, the Commission tends to propose directives because they give to the

member states more flexibility to interpret their national laws. From a procedural point of

1 Austria, Belgium, Denmark, Finland, France, Germany, Greece, Italy, Ireland, Luxembourg, the

Netherlands, Portugal, Spain, Sweden, and the United Kingdom.
Appendix D 83 Special Investigation Report

view, both regulations and directives are enacted in the same manner. Once there is EU

legislation on a subject, EU member states may not have additional national legislation

that in any way contradicts or conflicts with the EU legislation, even if the national

legislation predates the EU legislation. 

When the legislation has been proposed, the onus is on any member state that has

conflicting national legislation to lobby for adoption of its national law by the EU as a

whole. The idea is that if it is sufficient in one state, it should apply equally in all others. If

it is determined that a particular national requirement is not appropriate for the entire EU,

a time-based derogation may be granted by the EU’s Council of Ministers, allowing a

member state to have different rules for a period of time.

Occupant Crash Protection on Buses

In 1990, the EU issued a directive requiring the installation of lap belts at all

exposed seats2 in motorcoaches first placed into service on and after July 1, 1992.

An EU representative reported to Safety Board staff that as a consequence of two

catastrophic bus accidents in the United Kingdom, there was an outcry for the installation

of seat belts on all seats on school transport vehicles, motorcoaches, and minibuses. Had

there been no EU legislation requiring seat belts on motorcoaches, the United Kingdom

could have required the fitting of seat belts at any or all passenger seats in motorcoaches.

However, because 1990 EU legislation requiring lap belts only at exposed seats on

motorcoaches already existed, the United Kingdom was prevented from passing

legislation requiring seat belts at all passenger seats in all motorcoaches.

The United Kingdom requested that the already existing EU directive requiring lap

belts only at exposed seats in motorcoaches be amended to require belts at all seats in new

motorcoaches. The United Kingdom also enacted legislation requiring seat belts on buses

and motorcoaches transporting children in the United Kingdom, particularly for school

transport. By passing legislation based upon how a vehicle is used, the United Kingdom

circumvented the Commission’s seat belt directive on exposed seats. The United Kingdom

legislation requires installation of belts on all new vehicles and the retrofitting of belts on

all vehicles already in use that are used for transporting organized children’s groups.

During the consideration of the United Kingdom’s proposal that a directive be

issued requiring seat belts on all passenger seats in motorcoaches, the Commission

engaged the Cranfield Impact Centre in England to study the technical requirements for

seat belts in motorcoaches. The study3 concluded: 

2 Directive 90/628/EC amending Directive 77/541/EEC. Exposed seats are those seats in coaches that

do not have an energy-absorbing structure in front of them to protect a passenger who is thrown forward

during a frontal impact or sudden stop. Such seats are typically located at the first passenger seat row, at the

courier, or tour guide seat, in the entry/exit vestibule, at the center seat facing the aisle in the rearmost row,

and at forward-facing seats immediately aft of a table or a door. 3 Kecman, D., Ph.D., et. al., “Study of Technical Requirements for Fitment of Seat Belts in Buses and

Coaches,” Report to the European Commission, Cranfield Impact Centre, Ltd., Wharley End, Cranfield,

Bedford MK43 OAL, England, February 1995. 
Appendix D 84 Special Investigation Report

Lap and lap/shoulder belts can significantly reduce or prevent passenger ejection

in all seating positions, particularly in rollovers, offset front, and major side

impacts and also in exposed seating positions during front impacts. Ejection is a

major cause of death and severe injury.

It took more than 2 years to get the necessary majority from the member states on

the seat belt proposal. The seat belt legislation, Directive 96/36/EC, which was approved

by the Council of Ministers in June 1996, requires:

The fitting of lap/shoulder belts at all passenger seats on minibuses which have a

gross laden weight4

 less than or equal to 3.5 metric tons (7,716 pounds). This

requirement is applicable to all new vehicle designs5

 manufactured on and after

October 1, 1999, and is applicable to all vehicles that are first placed into service

on or after October 1, 2001.

The fitting of lap/shoulder belts at all exposed seats, and the fitting of either

lap/shoulder belts, or the fitting of lap belts aft of energy-absorbing seats, at all

other passenger seats on M26

 motorcoaches which have a gross laden weight

greater than 3.5 metric tons (7,716 pounds). These requirements are applicable to

all new vehicle designs manufactured on or after October 1, 1997, and are

applicable to all vehicles that are first placed into service on or after October 1,

1999.

The fitting of lap/shoulder belts at all exposed seats, and the fitting of either

lap/shoulder belts, or the fitting of lap belts aft of energy-absorbing seats, at all other

passenger seats on M37

 motorcoaches. These requirements are applicable to all new

vehicle designs manufactured on or after October 1, 1997, and are applicable to all

vehicles that begin service on or after October 1, 1999.

The June 1996 seat belt directive permits an EU member state to require a

motorcoach to comply with national legislation on seat belts. Yet, a vehicle does not have

to meet the EU legislation’s requirements unless the vehicle is a “new design” after

October 1, 1999. This lead time allows member states to set higher, possibly more

expansive, standards for already-existing motorcoach designs until that date. A member

state, for example, could insist on lap/shoulder belts at all seats in its own motorcoaches

now, but it can not refuse to permit the import of motorcoaches built to EU-approved

standards that differ from the state’s own national legislation. After October 1, 1999, an

EU member state cannot refuse admission into its country for sale or use any motorcoach

4 In determining the gross laden weight, a weight of 71 kilograms (156.5 pounds) is used for the weight

of each person/seat provided on the coach or minibus subject to the seat belt legislation. 5 A vehicle is a new design if it differs from already-approved types in any one or more of the

following: body work manufacturer, chassis manufacturer, vehicle class (I, II, III, A, and B), body work

concept (single/double deck, articulated, low floor), passenger capacity limit category, or a gross laden

weight differing by more than 10 percent from any already approved types. 

6 M2 vehicles have more than 8 seats in addition to the driver’s seat and a maximum weight of not

more than 5 metric tons (11,023 pounds). 7 M3 vehicles have more than 8 seats in addition to the driver’s seat and a maximum weight of more

than 5 metric tons (11,023 pounds).
Appendix D 85 Special Investigation Report

that meets the seat belt directive coming into effect on that date. A similar situation exists

for minibuses, with the cut-off date for minibuses being October 1, 2001.

Although an EU member state cannot require higher seat belt standards on

motorcoaches first placed into service after October 1, 1999, the state can enact national

legislation limiting how motorcoaches with lap belts at nonexposed seats are used. For

example, for some time motorcoaches in Germany have been allowed to operate at 100

km/h (62 mph) only if the exposed seats have occupant restraints. If such seats do not have

occupant restraints, German law limits the motorcoach’s maximum operating speed to 80

km/h (50 mph). At this time, nothing precludes this type of legislation in the EU member

states since the legislation does not conflict with existing EU legislation and will not

conflict with the new seat belt directive when the directive becomes effective. 

According to the Director General’s office, none of the countries within the EU

have vehicles dedicated to pupil transportation. There are no yellow school buses. The

majority of students travel to and from school either on municipal scheduled buses or

municipal buses that are chartered for school transportation. Motorcoach buses are also

chartered for school transportation and are usually the oldest buses in the fleet. A small

number of private schools provide transportation in minibus vehicles. 

According to the EU representative, the United Kingdom requires that vehicles

that are used primarily for the transportation of children have seat belts and that the belts

be worn. The question of who is responsible and liable for making the children wear the

belts has not been decided.

EU Studies of Bus Accidents

In 1985, the EU commissioned the Motor Industry Research Association to

investigate motorcoach bus safety. The report8 concluded that:

Although the casualty rate per passenger kilometer for motorcoach travelers is

low in relation to other forms of transport, when collisions do occur, large

numbers of people can be injured.... The ejection of passengers which increase

the chances of injury substantially would probably be best prevented by the use of

lap belts by passengers.... 

The protection of passengers in frontal impacts depends mainly on attenuating the

contact between the passenger and the seat that he is facing. Either the use of a

seat belt or controlled collapse of the seat can achieve this. A legislative

requirement should be established to improve seat crashworthiness that enables

both options to be available to the manufacturer.

A representative of the Commission advised the Safety Board that the EU

promulgated the directive requiring lap/shoulder belts on smaller vehicles on the grounds

that small vehicles perform like cars in crashes and, therefore, should meet analogous

8 The Motor Industry Research Association, Watling Street, Warwickshire CV10 0TU, England, “EEC

Coach Safety Investigation,” Report No. K454293, Investigation into Ways of Improving Coach Safety,

October 17, 1985. 
Appendix D 86 Special Investigation Report

requirements. The EU determined that most injuries and fatalities associated with the

smaller buses happened while the passengers were either boarding or alighting. On larger

vehicles, the evidence showed that approximately half the deaths and serious injuries were

caused by passengers being ejected during rollovers rather than being hurt during frontal

impacts. Therefore, the EU’s primary concern about accidents involving the larger

vehicles is to keep the passengers in place, not to protect them against impact injury.

The representative from the Cranfield Impact Centre stated in an interview that the

Centre’s research strongly supported the view that occupant protection is not just seat belts

but a total system including the belts, the seats, and the anchorages. He said that putting

seat belts on an improper seat can be disastrous and that restraint combinations have been

seen that performed worse with seat belts, especially lap belts, than without.

He also said that some car manufacturers who construct minibuses derived from

van designs objected to the seat belt legislation. The manufacturers anticipated problems

adapting their existing M2 minibus designs with gross laden weights of 3.5 metric tons

(7,716 pounds) or less to accommodate lap/shoulder belts. For this reason, the legislation

mandating lap/shoulder belts for these smaller vehicles will become effective 2 years after

the legislation for the larger vehicles does. 

EU Legislation for Seat and Seat Anchorage’s Strength

Directives specifying requirements for the strength of passenger seats, seat

anchorages, and seat belt anchorages were amended to accommodate the installation of

seat belts on all motorcoach passenger seats. This legislation did not require that

motorcoaches placed into service before October 1997 be retrofitted with seat belts.

The EU seat belt-anchorage directive specifies that the required strength of the seat

belt anchorages depends on the mass (gross weight) of the vehicle in which the anchorage

is installed. For seat belt-anchorage systems attached to the seats: M2 vehicles are

required to have seat anchorages capable of sustaining a quasi-static load equal to

approximately half the load required for anchorages on an M1 vehicle, and M3 vehicles

are required to have anchorages capable of sustaining a quasi-static load equal to

approximately one-third the load required for an M1 vehicle anchorage system. In lieu of a

quasi-static test, a sled test can be performed to test the seat anchorage system on M3

vehicles. For the sled test, two 50th-percentile male dummies are placed in the seat and

restrained. The maximum sled deceleration must be at least 8 g, and the velocity change,

Delta V, must be at least 18.6 mph.

The EU also requires that seats be energy absorbing to protect the unbelted

occupant from behind.

EU Legislation Mandating Seat Belt Use and Retrofit

Two issues that were deliberately not addressed in the EU seat belt legislation

relate to retrofitting and the mandatory use of seat belts. The Transport Directorate did not

want to require retrofitting because existing vehicles may not be designed for seat belts. In
Appendix D 87 Special Investigation Report

addition, retrofitting could be dangerous if the seats are not energy-absorbent and/or the

belt and seat anchorages can not withstand crash loading. 

Furthermore, testing retrofitted seat belts is difficult. Without a test procedure, it is

not possible to verify whether belts actually perform their necessary function in a crash.

Motorcoach operators can retrofit if they wish, since the EU legislation is silent on this

issue; and some motorcoach designs now in use may accommodate retrofitting.

The Commission said that the EU would probably not consider legislation on the

mandatory use of seat belts on motorcoaches for some considerable time. This is because

the vast majority of the European motorcoach fleet is not equipped with seat belts at all

seats. Approximately 35 percent9 of motorcoaches operated in 1997 in the EU member

states have lap belts at the exposed seats. The implementation date for installing seat belts

for present M3 and M2 motorcoach designs with a gross laden weight greater than 3.5

metric tons (7,716 pounds) was October 1999. Consequently, given that the average life of

a motorcoach is 15 years, it will probably be 2005 or 2006, before even half of the fleet is

fitted with seat belts. 

Another issue that has to be addressed before the Commission will consider

legislation mandating seat belt use is determining the liability for compliance. A Commission

representative advised the Safety Board that the pragmatic approach would be to equip

vehicles with seat belts and give every occupant the choice of wearing a seat belt or not.

Ideally, motorcoach seats would be designed in such a way that if one passenger is wearing a

seat belt and the passenger behind him is not, the belted passenger will not be injured by the

forward movement of the unbelted passenger during a collision. The seat will absorb the

energy of the unbelted occupant, causing minimal injuries to the unbelted passenger.

Bus Rollover

The EU has proposed legislation on the rollover strength of buses and

motorcoaches. The Commission’s Regulation 66 was the basis for the legislation. The

Commission believed that a directive specifying rollover strength in the bus construction

standards is essential for ensuring the effectiveness of the seat belt legislation. The

Commission believed that mandating seat belts without a rollover strength requirement

increases the risks to passengers if the roof crushes downward and decreases the available

space. This would occur only during 180-degree or greater rollovers. Ejections, which

cause half the fatalities and injuries, can occur when the motorcoach simply rolls onto its

side. At present, only the United Kingdom and Spain require compliance with the

Commission’s rollover strength requirements.

The proposed EU standard includes the requirement that any bus or motorcoach

pass a tilt test. The standard requires that a single-deck vehicle be able tilt up to 35 degrees

without rolling over. The ability to pass the tilt test has been a requirement in the United

9 Estimated using an average coach life of 15 years with an average of 7 percent of the coach fleet

being replaced each year. Since the legislation was passed 5 years ago in 1992, 5 X 7= 35 percent. 
Appendix D 88 Special Investigation Report

Kingdom for a number of years. Compliance with the tilt test indicates that the vehicle is

less likely to roll over during violent avoidance maneuvers.

Australian Bus Safety Issues

Australia has two categories of buses: urban buses, which are for both seated and

standing passengers, and motorcoaches, which are predominately for seated passengers.

Australia does not have school buses similar to those in the United States, which have to

meet higher standards. Australia has standards10 similar to those of the United States for

braking, lighting, and fuel tank integrity. In addition, Australian buses have speed limiters

and are required to meet a bus rollover standard.11 The standards for occupant protection

differ according to the category of bus.

Occupant Restraints

In motorcoach buses, the Australian standard12 requires lap/shoulder belts at all

seating positions. As with the EU requirement, the minimum seat anchorage system

strength for a seat with a unitized seat belt system can be established using a sled test. For

the test, two 50th-percentile male dummies are placed in the seat and restrained. The sled

deceleration for the test must be at least 20 g (approximately twice the EU requirement) and

the velocity change, Delta V, must be at least 30 mph. Regulators who designed the

standard wanted to protect restrained occupants from the unrestrained occupants seated

behind them. Therefore, when conducting a sled test, unbelted dummies are placed in the

seat behind the seat with the belted dummies if that seat exists in the actual coach. The

injury criteria for the unbelted occupant are not measured. (The EU sled test does not

require the unbelted dummies in the rear seat.) Australia does not require that the seat be

energy absorbing to protect the unbelted passenger from behind. The standard also requires

that six of the seats have upper tethers to use in conjunction with the child restraints.

In Australia, traveling by motorcoach is 20 times safer than traveling by private car,13

yet the new standards were the outcome of two serious motorcoach accidents in the late

1980s. In the first accident, a motorcoach and tractor-semitrailer collided head on; 20 people

were killed, and 15 were injured. Three months later on the same highway, two

motorcoaches collided head on, and 35 people were killed and 39 injured. Analysis14 of both

accidents found that several of the seat structures and mountings in all the motorcoaches

involved failed and caused many of the injuries. In response to these seat system failures,

regulations began to be developed for new seat systems based upon the European standards.

When it was found that the Stratos Seat Company had developed a seat that tested well when

subjected to a crash pulse deceleration approximately twice the European requirement, that

10 The standards are called Australian Design Rules and are the performance and design requirements

for motor vehicles. 11 Australian Design Rule Number 59.

12 Australian Design Rule Number 68.

13 “Bus Crashes and Occupant Protection, A Brief Summary and Analysis of Crashes Involving Long

Distance Coaches, Australia 1988 to 1994,” K.B. Smith, Federal Office of Road Safety, July, 1998. 14 “Cost Benefit Analysis of Retrofitting Occupant Protection Measures to Existing Buses,” K.B. Smith,

November 21, 1994.
Appendix D 89 Special Investigation Report

incorporated lap/shoulder belts, that could withstand an impact from behind of unbelted

occupants (not an EU requirement), and that could be installed in motorcoaches at an

affordable price, the standard was revised to incorporate those conditions. 

These regulations went into effect for all motorcoaches manufactured since 1994;

and, currently, most motorcoaches have the new seat-restraint systems. Also, the

government developed a code for the retrofit of existing motorcoaches using the 10-g

seats and lap belts. This is not a mandatory requirement but a voluntary code.

A motorcoach with the new seat system has had an accident. Fully occupied, it

struck a culvert at highway speeds. Two passengers were fatally injured; neither had been

restrained. One had been walking down the aisle; and the other, the reserve driver, had

been in the sleeper cab, which was at in the back of the bus. More studies are being done

to determine the performance of the new occupant restraint system.

In Australia, if a restraint is provided, it must be used, and its use is enforced by the

state police. According to studies,15 approximately 95 to 98 percent of front-seat

passengers and 80 to 85 percent of rear-seat passengers use the restraints. In buses, the

driver is not responsible if an occupant does not use an available restraint. The driver is

responsible only for providing information about the laws to the passengers. In the case of

a motorcoach, a passenger who does not wear a seat belt can be fined $200 to $300, and

the driver gets demerit points on his license. There are no controls in place to ensure that

school-age children utilizing the bus for pupil transportation wear restraints.

Rollover Standards

All buses in Australia are required to meet a bus rollover standard,16 which is based

on the United Nations Economic Commission for Europe (UNECE)17 Regulation 66. The

standard requires that the bus be able to maintain an internal space within specified

dimensions after it is tipped onto its side. The results of crash testing motorcoaches were

used in developing the standard and in validating computer simulations. The validation

made it possible to rely more on computer simulations than on actual crashes.

Australia has had crashes in which rollovers and partial ejections have caused

injuries that were not life threatening but were extremely debilitating. Preventing occupant

ejection has been a priority.

15 Development of an Australian Design Rule for Seat Belts in Heavy Omnibuses, Alan Gascoyne, Keith

Seyer, Federal Office of Road Safety, Australia, 1994.

16 Australian Design Rule Number 59.

17 The UNECE is a subgroup of the United Nations. It was started at the end of World War II to promote

trade in Europe by harmonizing the requirements of various countries. Membership is voluntary, and

member states do not have to comply with UNECE legislation.
90 Special Investigation Report

Appendix E

History of Restraint Recommendations 

to the FHWA and to NHTSA
Recommendation Action Response Safety Recommendation H-68-18 asked the FHWA to expedite the proceeding initiated under Part II of the Interstate Commerce Act, Docket Ex Parte No. MC-69, May 27, 1966: to inquire into the operations of motor carriers of passengers in order to determine whether it is necessary or desirable to adopt regulations and establish standards which would require carriers to install, provide, and maintain seat belts for the use of passengers and drivers. Closed—Superseded by H-73-42 between December 12 and 16, 1985. (For more information, see response to H-70-4.) In its January 17, 1969, letter, the FHWA indicated that initial acti

No. MC-69, initiated in May 1966, was delayed pending the trans1967, of responsibility for the FMVSS. The FHWA stated that it dBoard’s position that belts should be required for bus occupants installation and use of lap belts for drivers of buses in interstate cIn its August 23, 1974, letter, the FHWA indicated that tests condthat seat belts are used by only a small percentage of occupantscombined with the small number of bus fatalities subject to BMCestimated number of injuries that might be prevented by belt usacost/benefits. In its May 2, 1979, letter, the FHWA stated that the study indicates that lap belts for all seats on both old and new intfeasible if used 100 percent of the time. Safety Recommendation H-70-4 asked the FHWA to take additional steps to make available to bus passengers convenient restraints to prevent ejection in a crash or rollover, such as are available to motorists and airline passengers, so that passengers will not be denied the opportunity to employ them. Closed—Superseded by H-73-42 between December 12 and 15, 1985. (Note: From 1968 through 1973, the Safety Board issued several safety recommendations calling for studies or rules regarding the availability of seat belts on buses. As a housekeeping measure, the Board closed three of the four remaining recommendations on the issue: H-68-18, H-70-4, and H-73-7.) In its April 7, 1970, letter, the FHWA advised the Safety Board of 

proposed rulemaking on driver seat belt requirements. The FHWnot to require passenger belts because of retrofit problems. In its August 8, 1974, letter, the FHWA indicated that tests conduseat belt usage by only a small percentage of occupants. This lowith the small number of bus fatalities subject to BMCS jurisdictioestimated number of injuries that might be prevented by belt usanegative cost/benefits. In its May 2, 1979, letter, the FHWA stated that the bus passengeindicates that lap belts for all seats on both old and new intercity if used 100 percent of the time.
Safety Recommendation H-71-10 asked the FHWA to expand its rulemaking concerning section 393.33 (seat belts) of the FMCSR in 49 CFR 393 to require in all buses, the installation of occupant restraints, active or passive, that conform to the FMVSS 209 and that will retain the passengers, as well as the driver, in their seats during collision and rollover. Closed—Unacceptable Action on October 29, 1975. In its August 23, 1974, letter, the FHWA stated: The BMCS has replied to this recommendation on numerous 

conducted by BMCS show seat belt usage by only a small peThis usage fact and the small number of bus fatalities subject (31 in 1972) and the calculation of the number of injuries that belt usage, indicate negative cost/benefits. In many buses, beimpracticable because they were not designed for belt use anthe floor loadings. Safety Recommendation H-71-11 asked NHTSA, in the development of its rulemaking related to Docket 2-11, Bus Seats, to include the requirement for the installation of seat belt assemblies, as well as seat belt anchorages, for intercity buses. Closed—Acceptable Action on January 1, 1980. In its April 6, 1971, letter, NHTSA indicated that it is developing a

passenger seating and crash protection. This NPRM would requibus seating over current design and is being approached from a to include a combination of the following: effective energy-absorbseat surfaces, higher seat backs, strengthening of seat structureaddition, safety belts are being considered. The seating system da reasonable level of passive restraint protection in most crash c

Safety Recommendation H-71-34 asked the FHWA to expand its rulemaking concerning section 393.95 (seat belts) of the FMCSR in to require in all interstate buses the installation of occupant restraints, active or passive, that conform to the FMVSS 209. Closed—Unacceptable Action on October 29, 1975. In its June 6, 1971, letter, the FHWA, in response to Safety Reco

through -36, restated its position that lap belts used in connectiobus seat configurations would act as a fulcrum and cause the uptarget the head into the adjacent structures in ways that would inThe FHWA does not recommend seat belts or “fasten seat belt” sIn its June 14, 1971, letter, NHTSA stated: There is little evidence to support the conclusion that the use 

significantly reduced the injuries of the contained passengersprotection for bus occupants is presently being approached frstandpoint (combination of effective energy-absorbing materiahigher seat backs, and strengthening of seat surfaces and an

Recommendation Action Response
Safety Recommendation H-71-35 asked the National Highway Safety Bureau (now NHTSA) in the development of its rulemaking related to Docket 2-11, Bus Seats, to include the requirement for the installation of seat belt assemblies, as well as seat belt anchorages, for interstate buses. Closed—Unacceptable Action on October 29, 1975. See response to Safety Recommendation H-71-34. Safety Recommendation H-71-87 asked the FHWA to take positive steps to make available to bus passengers convenient restraints to prevent ejection in a crash or rollover. (This recommendation, with similar intent but varying language, had been made by the Safety Board in four previous reports on interstate bus crashes.) Closed—Unacceptable Action on March 29, 1975. In its December 22, 1971, letter, the FHWA reiterated its position 

occupant-protection problem will be a passive restraint approachpassenger ejection and to mitigate injury caused by contact with FHWA further stated that containment can be effectively assured governing seat configuration and the mounting and latching of w

Safety Recommendation H-73-1 asked the FHWA and NHTSA to institute appropriate rulemaking action to require that all newly constructed interstate-type buses be equipped with approved occupant restraints, active or passive, for all seating positions in such buses. Closed—Acceptable Action on January 1, 1980. In its March 21, 1973, letter, NHTSA stated: With regard to the recommendation to provide seat belts for a

buses, you may be interested in the recent Notice of Propose

Passenger Seating and Crash Protection, printed in the Fede

No. 35, on February 22, 1973. The National Highway Traffic Sthis proposal would require bus passenger seats which are stwhich afford greater protection to bus passengers. In additionsystem employing seat belts equipped with a warning system these proposed requirements. The standard as proposed wouall types manufactured after September 1, 1974. In its August 23, 1974, letter, the FHWA indicated that this recom

been acted on by NHTSA and, therefore, required no further actiBMCS further stated that the responses to the NPRM had been aNPRM, 49 CFR 571, Docket 73-3, Notice 2, was being issued widate of January 1, 1976. Recommendation Action Response
Safety Recommendation H-73-7 asked NHTSA and the BMCS to take immediate action toward requiring the availability of seat restraints for passengers of buses in interstate commerce, with first attention given to restraints in newly manufactured buses. Closed—Superseded on December 12, 1985. In its April 23, 1973, memorandum, the FHWA stated: The Bureau has responded to Recommendation H-73-7, pert

restraints, on numerous occasions, including the Safety BoarMarshfield, Missouri, accident (Report No. NTSB-HAR-73-1). become available to suggest a revision of our views on this m

In its May 10, 1973, letter, NHTSA indicated that based on the Srecommendations and other available accident data and test datof Proposed Rulemaking on Bus Passenger Seating and Crash P1973, noting that: This proposed rulemaking allows two options for occupant res

offers passive restraint protection by means of very strong, wseats which compartmentalize the passenger compartment focontainment during most crashes. The second option offers awhich includes padded high seat backs, lap belts, and warnindegree of belt usage. NHTSA feels that allowing two approximapproaches to the passenger protection problem will minimize permitting bus operators to choose the system that best fits th

Safety Recommendation H-73-18 asked NHTSA to require that seats on intercity buses be upgraded to provide a defined level of protection for passengers who do not use installed restraints and also to require the seat strength and seat belt performance standards called for in the proposed rulemaking. Closed—Unacceptable Action on August 13, 1997. NHTSA, in its August 13, 1974, letter, stated that it had determin

requirements cannot be justified based on cost/benefit studies anindicating that seating improvements on intercity buses would nosubstantially. Recommendation Action Response
Safety Recommendation H-73-42 asked the BMCS to take positive steps to make available to bus passengers convenient restraints to prevent ejection in a crash or rollover. (This recommendation, with similar intent but varying language, had been made by the Safety Board in seven previous reports on interstate bus crashes.) Closed—Reconsidered on June 29, 1988. In its February 11, 1974, memorandum, the FHWA, in response to 

H-73-42, stated: Both the Bureau of Motor Carrier Safety and the National Hig

Administration have faced the problem of occupant ejections combination of double-latched windows (BMCS Docket No. MVehicle Safety Standard No. 217, effective July 1 and Septemand improved seating and crash protection in new buses (NHapproach the problem in a way we expect, in the long run, to less costly and more easily accepted by the public. In its April 22, 1988, letter, the FHWA stated: In response to this recommendation, the FHWA initiated reseaby the Indiana University. A copy of the research report, Analy

Passenger Safety Belt Requirements in Intercity Buses, was 

September 13, 1985, letter. The researchers concluded that noptions studied had a favorable benefit/cost ratio at the anticipuse rates. Based on this research, it was recommended that passenger safety belts in intercity buses be issued. In its June 29, 1988, response to the FHWA’s April 22, 1988 lette

Board replied: The Safety Board’s most recent major accident experience w

intercity buses is based on our investigation of the North BergArkansas; and Carney’s Point, New Jersey bus accidents. Duit was observed: (1) Generally, the installation and use of lap belts would not houtcome for passengers who sustained minor to moderate inj(2) The injury outcome of the remaining passengers who sustinjuries in these accidents was less predictable. Normally, lap lessened the injury severity for the serious to fatally injured paseated in areas which were intruded during impact. (3) However, in the North Bergen accident, the installation anhave reduced the injury severity of two passengers who were intruded-upon areas into the rearward moving front structure Based on these findings, it seems appropriate to classify SafeH-73-42 as “Closed—Reconsidered.” However, it should be nobservations were made in accidents involving primarily frontin accidents involving bus rollovers. The Safety Board will conbus accidents to test these observations. Recommendation Action Response
96 Special Investigation Report

Appendix F

Summaries of Selected1 Motorcoach2 Accidents Investigated 

by the Safety Board From 1968 Through 1997

CASE 1

A 1966 MCI Challenger Model MC-5A motorcoach on a regularly scheduled run

was traveling in the eastbound median lane of Interstate Highway 15 when it collided

nearly head on with an automobile being driven westbound in the same lane by an

intoxicated driver. The force of the collision drove the automobile about 45 feet east of the

point of impact, killing the automobile driver instantly and ejecting his body from the

automobile.

After impact, the motorcoach swerved left into the median and overturned onto its

right side. The motorcoach had four windows on each side; the windows were hinged at

the top, latched at the bottom, and designed as emergency exits. During the collision and

subsequent overturn, the motorcoach was twisted, causing some of the side windows to

spring open. Portions of passengers’ bodies, such as legs, arms, and hands, were ejected

and protruded through the windows; and as the overturned motorcoach came to rest, at

least three passengers were pinned under it.

Fire, fed by leaking power steering fluid and diesel fuel from the breached fuel

tank, spread immediately throughout the motorcoach. The driver and 6 of the 14

passengers seated in the first four rows escaped through the windshield. Five passengers

seated in the last three rows at the left rear of the motorcoach smashed the rear window

and escaped through it.

1 Forty crashes in which one or more passengers who sustained fatal injuries either were found inside

the vehicle or were ejected, and one crash in which passengers survived but lost limbs because they were

partially or completely ejected. 2 Accidents 13, 20, 33, and 35 are not motorcoach fatalities and are not included in motorcoach data in

the report.

Date and Time March 7, 1968, 3:47 p.m.

Date Report Adopted December 18, 1968

Accident No. NTSB/SS-H-3

Location Near Baker, California

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 19 Fatal, 12 Nonfatal

Type of Crash Head-On Collision With Automobile and 

Subsequent Overturn
Appendix F 97 Special Investigation Report

The 19 passengers who did not escape died in the fire. A pathologist who partially

examined 12 of the dead passengers reported that, although he observed fractured

extremities, he observed no injuries which, of themselves, would have been fatal.

As a result of its investigation of this crash, the Safety Board recommended that

the Federal Highway Administration (FHWA):

H-68-18

Expedite the proceeding initiated under Part II of the Interstate Commerce Act,

docket Ex Parte No. MC-69, dated May 27, 1966, to inquire into the operations of

motor car5riers of passengers in order to determine whether it is necessary or

desirable to adopt regulations and establish standards which would require

carriers to install, provide, and maintain seat belts for the use of passengers and

drivers. 

The Safety Board said:

The experience in this case indicates definitely that restraint of drivers and

occupants in their seats during rollover conditions is necessary to reduce initial

injury, disorientation, and thus ensure more likelihood of timely postcrash escape

from the vehicle. The FHWA Administrator in reaching his decision concerning a

requirement that seat belts be available in buses should seriously consider this

report and the Safety Board’s conclusion. The Safety Board urges that a decision be

made on this important matter, which has been under consideration for more than

22 months at the time this accident occurred, and more than 30 months prior to the

date of this report.

The Safety Board also recommended that the FHWA:

H-68-25

As soon as possible, change the basis of its regulatory requirements intended to

ensure escape from buses so that they are based upon tests of performance of

occupants in escaping from buses standing or lying in all basic attitudes. In the

development of test criteria, it is suggested that consideration be given to test

procedures presently employed by the Federal Aviation Administration for the

regulation of the adequacy of escape techniques and systems. Further,

consideration should be given to adopting for buses, the airline practice of placing

emergency escape instructions at each passenger location. It is further

recommended that necessary regulations be expedited to ensure that no new types

of buses go into service which have not been tested to ensure that all occupants

can escape rapidly when the bus is in any of its basic attitudes after a crash. This

Recommendation refers to Docket 2-10 of the National Highway Safety Bureau3

as well as the Motor Carrier Safety Regulations.

3 At the time this recommendation was issued, the National Highway Safety Bureau, predecessor of

NHTSA, was part of the FHWA.
Appendix F 98 Special Investigation Report

CASE 2

A chartered 1968 Challenger Model MC5A motorcoach traveling eastbound on

Interstate Highway I-80 South traveled straight ahead as it entered a left curve and ran off

the roadway to the right. The driver made a hard left turn, and the motorcoach yawed to

the left and re-entered the roadway. After a hard right turn, the motorcoach again ran off

the roadway to the right. Another hard left turn made as the driver again attempted to

return to the roadway caused the motorcoach to vault and roll over onto its roof. After

rolling over, the inverted motorcoach rotated 180 degrees and slid east down about 12 feet

into a drainage gully, coming to rest facing west. Its roof and left side were lying on the

bottom of the gully. 

Thirteen passengers and the driver were hospitalized with moderate to severe

injuries. Another 23 passengers were treated for minor injuries and released. One

passenger, who had been seated in the right third-row window seat, was crushed between a

seatback and a collapsed roof support. Another passenger, who had been seated in a

window seat in the left ninth row, was partially ejected through the adjacent window and

was pinned in the collapsed window frame as the motorcoach came to rest on its roof.

Both victims died immediately. 

A third passenger, who had been seated in the window seat immediately behind the

driver, sustained injuries that caused death about an hour after the crash. She was ejected

from her seat forward and to the right into the entrance stairwell.

The Safety Board concluded that occupant restraints would have reduced the

number of injuries the surviving passengers sustained and possibly would have reduced

the severity of the injuries sustained by the woman who died after the accident. The Board

was uncertain whether restraints would have prevented the other two fatalities, because

both fatalities resulted from structural damage. 

As a result of its investigation of this crash, the Safety Board recommended that

the FHWA:

H-70-4

Take additional steps toward making available to the bus-traveling public

convenient restraints against being ejected from their seats in a crash, such as are

Date and Time December 26, 1968, 2:40 a.m.

Date Report Adopted January 23, 1970

Accident No. NTSB/SS-H-5

Location Near Beaver Falls, Pennsylvania

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 3 Fatal, 36 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 99 Special Investigation Report

available to motorists and airline passengers, so that passengers will not be denied

the opportunity to employ them if they so desire.

The Board said that in its view: 

A decision to make available suitable restraints which would reduce injuries is not

dependent upon a showing that all passengers would use them, nor should it be

limited by the fact that past bus passenger seat designs do not accommodate the

lap belt type restraint. The retention of passengers in their seats during the crash

phase is clearly desirable, as indicated by this case and others, and making

restraints available is a first step in obtaining their use.

The Safety Board also recommended that the FHWA:

H-70-9

Review our recommendation in the report of the Interstate bus-auto collision near

Baker, California, to change the basis of regulatory requirements intended to

ensure escape from buses so that they are based upon tests of performance of

occupants in escaping from buses standing or lying in all basic attitudes. In the

development of test criteria, it is suggested that consideration be given to test

procedures presently employed by the Federal Aviation Administration for the

regulation of the adequacy of escape techniques and systems. Further,

consideration should be given to adopting for buses, the airline practice of placing

emergency escape instructions at each passenger location. It is further

recommended that necessary regulations be expedited to ensure that no new types

of buses go into service which have not been tested to ensure that all occupants

can escape rapidly when the bus is in any of its basic attitudes after a crash. This

recommendation refers to Docket 2-10 of the National Highway Safety Bureau, as

well as the Motor Carrier Safety Regulations. 
Appendix F 100 Special Investigation Report

CASE 3

A 1966 GMC Model PD4107 motorcoach on a regularly scheduled run was

traveling southbound on Indiana Route 57 in heavy fog and darkness when the driver,

believing headlights ahead indicated an automobile approaching in the motorcoach’s

travel lane, swerved to the right and applied the brakes. The motorcoach rotated

clockwise, skidded, and struck the automobile broadside. (The automobile was, in fact,

stopped at an intersection waiting to enter Route 57 from the west.) After colliding with

the automobile, the motorcoach rolled over 270 degrees in a southwesterly direction,

coming to rest on its right side on an embankment.

A 4-month-old infant, who was lying on her mother’s lap in a plastic infant carrier

before the overturn, sustained a fatal blow to the head during the crash. Her body and the

infant carrier were found in a concrete drainage ditch near the motorcoach. The Safety

Board determined that she and the carrier had been ejected through the window next to

where her mother had been sitting (the left rear). The driver and the 25 remaining

passengers were not ejected and sustained minor to serious injuries, resulting from

secondary collisions with the armrests of the seats, the overhead luggage racks, and other

interior fixtures of the motorcoach, during the rollover. The automobile driver sustained

minor injuries.

The Safety Board concluded that had occupant restraints been available and used,

the motorcoach’s driver and passengers would have sustained fewer and less severe

injuries. As a result of its investigation, on June 1, 1971, the Safety Board made the

following recommendation to the FHWA:

H-71-34

Expand its rulemaking concerning Section 393.93 (seat belts) of the Motor Carrier

Safety Regulations in Part 393 of Title 49, Code of Federal Regulations, to

require in all interstate buses the installation of occupant restraints, active or

passive, that conform to the MVSS 209. 

The Board made the recommendation in a report it released on December 31,

1968, called Interstate Bus-Auto Collision near Baker, California, and made the

recommendation again in Chartered Interstate Bus Crash Interstate I-80S near Beaver

Falls, Pennsylvania. In the Board’s view, a decision to make available suitable restraints

Date and Time November 24, 1969, 5:15 a.m.

Date Report Adopted February 10, 1971

Accident No. NTSB/HAR-71-4

Location Near Petersburg, Indiana

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 1 Fatal, 25 Nonfatal

Type of Crash Collision With Automobile Followed by 

Motorcoach Overturn
Appendix F 101 Special Investigation Report

that reduce injuries is not dependent upon a showing that all passengers would use the

restraints, nor should the decision be affected by the fact that past bus passenger seat

designs do not accommodate the lap-belt type of restraint.

The Safety Board also made the following recommendations:

H-71-35

NHTSA [should], in the development of its rulemaking related to Docket 2-11,

Bus Seats, include the requirement for the installation of seat-belt assemblies as

well as seat-belt anchorages for interstate buses.

H-71-36

The FHWA and NHTSA, in their rulemaking as recommended above, [should]

include the requirement that occupants of interstate buses be advised, both by a

“Fasten Seat Belt” illuminated sign and by notification by the driver, to fasten seat

belts.

H-71-37

NHTSA should study the feasibility and practicality of a standard for passenger

buses requiring that overhead surfaces, which include roof linings, moldings,

parcel or luggage shelves, edges, and support hardware, be designed so as to

reduce or prevent direct contact injuries in rollover and upset accidents, and that

such areas resist separation or fracture of a type which would expose edges to

passengers. Such protection is of particular importance in the absence of

passenger restraints not currently required. 
Appendix F 102 Special Investigation Report

CASE 4

A 1967 GMC Model PD4107 motorcoach on a regularly scheduled run was

traveling in the eastbound median lane of the four-lane divided Dulles Airport access road

when the driver saw an oncoming automobile traveling the wrong way in the

motorcoach’s traffic lane. The automobile driver was intoxicated. Although the

automobile driver initiated an evasive maneuver to the left, the right front of the

automobile collided with the right front of the motorcoach. After impact, the motorcoach

continued eastbound and came to rest upright in the highway median, 278 feet from the

point of impact.

The motorcoach had eight passengers, all of whom were seated in the first three

rows. The motorcoach’s right windshield popped out on impact, and the passenger in the

right front seat was ejected through the windshield and fractured his spine and ribs as he

struck the pavement. A passenger seated in the right second row was ejected forward

down the center aisle and was restrained within the motorcoach by the driver at the front

of the motorcoach. This passenger fractured his leg and died 20 days later from a blood

clot that developed due to his injury. The driver, who was not using the lap belt, and the

remaining six passengers sustained minor to moderate injuries. The driver of the

automobile was killed.

As a result of its investigation, the Safety Board concluded: 

The presence and use of passenger restraints in the bus could have reduced the

severity of injuries suffered in that vehicle. Such restraints would have contained

the ejected passenger and the fatal passenger in their seats, reducing the severity

of their injuries. 

On March 29, 1971, the Safety Board recommended that:

H-71-10

The FHWA expand its rulemaking concerning Section 393.33 (seat belts) of the

Motor Carrier Safety Regulations in 49 CFR 393.33 by requiring in all buses the

installation of occupant restraints, active or passive, that conform to MVSS 209

and will retain the passengers, as well as the driver, in their seats during collision

and rollover.

The Board has recommended in two of its accident reports, Interstate Bus-Auto

Collision near Baker, California, March 7, 1968, and Chartered Interstate Bus Crash near

Date and Time June 9, 1970, 4:40 p.m.

Date Report Adopted December 30, 1970

Accident No. NTSB/HAR-71-2

Location Near Chantilly, Virginia

Operator Greyhound Airport Service

Motorcoach Passenger Injuries 1 Fatal, 7 Nonfatal

Type of Crash Head-On Collision With Automobile
Appendix F 103 Special Investigation Report

Beaver Falls, Pennsylvania, December 26, 1968, that the FHWA consider its rulemaking

and pending dockets on installing seat belts. The present regulation (Section 393.33)

requires seat belts for drivers but not for passengers. In the Board’s view, a decision to

make available suitable restraints that would reduce injuries is not dependent upon a

showing that all passengers would use the restraints, nor should the decision be affected

by the fact that past bus passenger seat designs do not accommodate the lap belts.

Retaining passengers in their seats during a crash is clearly desirable, as indicated by this

case and others; and making restraints available is a first step.

The Safety Board also recommended that:

H-71-11

NHTSA, in the development of its rulemaking related to Docket 2-11, Bus Seats,

include the requirement for the installation of seat-belt assemblies, as well as seatbelt anchorages, for intercity buses.
Appendix F 104 Special Investigation Report

CASE 5

A chartered 1967 GMC Model SDM5302 motorcoach carrying 53 school-age

children and their counselors on a sightseeing trip was going westbound about 55 mph on

Interstate Highway 78 (U.S. Route 22) during a rainstorm when the motorcoach crossed a

section of highway that was covered with water. The motorcoach went out of control,

rotated clockwise 180 degrees, traveled through a roadside cable guardrail, and vaulted

down a 50-foot embankment, where it came to rest on its left side.

During the vault and overturn, 18 passengers were ejected from the side windows,

the windshield, or the rear window; and 6 of the ejected passengers were pinned under the

left side of the motorcoach when it came to rest. Four of the pinned passengers sustained

fatal injuries. Two ejected passengers were not pinned but also sustained fatal injuries.

After the motorcoach came to rest, the seventh fatally injured passenger escaped or was

carried through the opening created when the rear window popped out. The driver and the

remaining 46 passengers sustained minor to serious injuries.

The Safety Board concluded, “The availability and use of passenger restraints,

such as seat belts, would probably have served to mitigate the degree of injury sustained

by many passengers.”

The Safety Board recommended that the FHWA:

H-71-87

Take positive steps toward making available to the bus-traveling public

convenient restraints against being ejected from their seats in a crash or rollover,

such as are available to motorists and to airline passengers, so that bus passengers

will not be denied their rightful opportunity to employ them whenever they so

desire. 

(Four previous Safety Board reports about interstate bus crashes had included a

similar recommendation.)

Date and Time July 15, 1970, 1:55 p.m.

Date Report Adopted September 8, 1971

Accident No. NTSB/HAR-71-8

Location Near New Smithville, Pennsylvania

Operator Tudesco Bus Service

Motorcoach Passenger Injuries 7 Fatal, 46 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Rollover
Appendix F 105 Special Investigation Report

CASE 6

A 1970 MCI Model MC-7 motorcoach on a regularly scheduled run was traveling

westbound on U.S. 66 when it collided with the left side of a station wagon that was

crosswise, either moving slowly forward or standing still, in the westbound lanes of the

four-lane divided highway. The driver of the station wagon was intoxicated.

After the collision, the motorcoach rotated clockwise and skidded about 150 feet

on the pavement, left the pavement, and, after crossing the shoulder, vaulted into a

drainage ditch, where it rolled over 450 degrees and came to rest on its left side about 288

feet from the point of impact.

Four motorcoach passengers were fatally injured, including one of the five

passengers ejected through the side windows and including the two passengers who were

crushed by the collapse of the roof onto their seats. All the other 33 passengers and the

driver sustained moderate to severe injuries.

The Safety Board concluded that had seat belts or some other form of restraint

been available and used by the motorcoach passengers, the number of injuries and

fatalities would have smaller. The Safety Board also concluded that the strength of the

roof support structure of the “picture-window” type of bus was inadequate. The structure

permitted gross downward and sideward deflection of the roof in a moderate rollover. The

bus exhibited critical localized structural failure in side-window posts as a result of a

design that permitted loads to be concentrated at points that could not compensate for the

stress. 

As a result of its investigation of this accident, the Safety Board recommended that:

H-73-1

The FHWA and NHTSA institute appropriate rulemaking action to require all

newly constructed interstate-type buses be equipped with approved occupant

restraints, active or passive, for all seating positions in such buses.

The Board had recommended the same action in four other accident reports, which

were released on December 31, 1968, March 19, 1970, June 1, 1971, and November 1,

1971, respectively. Such rulemaking would carry out the intent of the National Highway

Date and Time October 10, 1971, 2:05 a.m.

Date Report Adopted January 31, 1973

Accident No. NTSB/HAR-73-1

Location Near Marshfield, Missouri

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 4 Fatal, 33 Nonfatal

Type of Crash Collision With Another Vehicle Followed by 

Motorcoach Overturn
Appendix F 106 Special Investigation Report

Safety Bureau (later NHTSA) expressed in the “Preamble to Amendment to MVSS 208,”

Docket 2-13, Notice 3, on September 30, 1970, by the acting director: 

The extension of Standard No. 208 is based on the proposition that, so far as

practicable, drivers and passengers in all types of vehicles should be afforded the

means of protecting themselves from personal injury that seat belts provide . . .

The Safety Board also recommended that:

H-73-3

The Bureau of Motor Carrier Safety (BMCS), FHWA, review intercity bus design

and the types of damage suffered in rollover accidents in an attempt to determine

whether structural strength in the window areas may have been reduced in recent

years in buses having very large side windows; and the BMCS prepare a rollover

performance test, or other performance tests, for buses which can reveal the

structural strength of buses in the areas stressed by rollover.

H-73-4

The manufacturers of intercity buses review their existing designs of buses having

very large side windows to determine whether it is technically feasible to prevent

critical localized structural failures and to increase the general strength of the

window area of buses by the use of greater-strength window columns, by

employing a larger number of continuous structural members through the window

area, and by using smaller windows.
Appendix F 107 Special Investigation Report

CASE 7

A 1955 GMC Model PD4501 motorcoach on a regularly scheduled run was

traveling eastbound on U.S. Route 11W, a two-lane highway, and started to pass an

eastbound automobile. As the front of the motorcoach pulled even with the automobile’s

door, a westbound truck came into view around a curve. The motorcoach driver apparently

made no attempt to return to the eastbound lane, and the motorcoach collided nearly head

on with the truck.

The motorcoach driver was killed. At least three motorcoach passengers who

sustained fatal injuries were ejected from the motorcoach before it came to rest. Two of

them were found under the rear of the motorcoach’s wreckage, and one was found west

and south of the motorcoach’s final rest position. The Safety Board was unable to

determine with certainty how many other motorcoach passengers were ejected. The

rescuers found four more dead passengers to the left and front of the motorcoach. A

witness reported observing another motorcoach passenger spill out of the motorcoach

after it came to a final rest. This passenger died en route to a hospital. Two survivors

recalled “waking up” outside the motorcoach, but did not remember how they got there.

Approximately three-quarters of the seats on the motorcoach were displaced or

twisted to some degree. The interior paneling on the roof and sidewalls was split, and

sharp edges were exposed. 

The Safety Board concluded that the installation of passenger restraints in the

motorcoach and their use by the passengers would have prevented some ejections and

reduced the severity of some of the injuries. The Safety Board also concluded that the

fracturing and splitting of the interior panels and the failure of the seats contributed to the

severity of the injuries.

As a result of its investigation of this crash, the Safety Board recommended that

the BMCS of the FHWA:

H-73-42

Take positive action toward making available to bus passengers convenient

restraints against being ejected from their seats in a crash or rollover. 

Date and Time May 13, 1972, 5:35 a.m.

Date Report Adopted October 25, 1973

Accident No. NTSB/HAR-73-5

Location Near Bean Station, Tennessee

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 12 Fatal, 15 Nonfatal

Type of Crash Head-On Collision With Tractor-Semitrailer
Appendix F 108 Special Investigation Report

A similar recommendation had been made in seven previous interstate bus crash

reports issued by the Safety Board.

The Safety Board also recommended that NHTSA:

H-73-43

Revise part S7.1 of its proposed rulemaking—Bus Passenger Seating and Crash

Protection, Docket 73-3; Notice 1, to require impact protection for interior panels

located in and around bus passenger windows. 
Appendix F 109 Special Investigation Report

CASE 8

A 1964 GMC Model 4106 motorcoach on a regularly scheduled run was traveling

southbound on Interstate 95 when it traveled straight ahead in a right-hand curve and

struck a median barrier rail. The motorcoach was then redirected across the southbound

lanes and began a counterclockwise rotation. After leaving the roadway, the motorcoach

struck a guardrail on the west side of the roadway and vaulted off the highway. After

landing on its roof, the motorcoach slid backward down a steep embankment before

coming to rest.

The Safety Board estimated that 20 passengers were probably ejected through the

side windows during the final movement of the motorcoach. Two passengers who

remained in the motorcoach were killed, as was one of the ejected passengers. The driver

and the 39 surviving passengers were injured to varying degrees.

The Safety Board concluded that the availability and use of passenger seat belts

would have reduced or eliminated the number of ejections, as well as the secondary

impacts of passengers into overhead components and into other tumbling passengers. That

the side windows were forced open by rollover-induced stresses contributed to the number

of ejections.

As a result of its investigation of this crash, the Safety Board recommended that:

H-73-6

The BMCS of the FHWA maintain close surveillance over the performance of bus

side windows in rollover crashes involving those buses which are required to meet

the provisions of Section 393.61 of the Motor Carrier Safety Regulations,

effective July 1, 1973, to determine as soon as possible whether these provisions

will produce the degree of window retention contemplated in the Regulations and

still permit effective escape of occupants via the side windows. 

H-73-7

NHTSA and the BMCS take immediate action toward requiring the availability of

seat restraints for passengers of buses in interstate commerce. First attention

should be given to restraints in buses of new manufacture.

Date and Time September 3, 1972, 2:20 a.m.

Date Report Adopted February 23, 1973

Accident No. NTSB/HAR-73-2

Location Richmond, Virginia

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 3 Fatal, 39 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 110 Special Investigation Report

CASE 9

A chartered 1953 GMC Model 4501SL motorcoach was traveling eastbound on I880 near Sacramento, California, when it ran off the road to its left, overrode a guardrail,

and collided with a bridge column. The preimpact speed of the motorcoach was estimated

to be about 67 mph, and the 48-inch-diameter column penetrated through 21 feet of the

center front of the 40-foot-long motorcoach. The driver and 12 passengers were killed; 22

passengers were hospitalized for moderate to critical injuries; 11 passengers were treated

for minor injuries. 

The motorcoach had a two-level passenger space; the front level had seats for 10

passengers (two double-seat rows left and three double-seat rows right of the center aisle).

The rear level, which had a floor 28 inches higher than the front, had seats for 37 passengers

(eight double-seat rows on each side of the center aisle, and a five-seat row in the rear).

The motorcoach had five windows on each side. The windows were hinged at the

top, latched at the bottom, and designed as exits in an emergency. Immediately after the

crash, some motorcoach windows were opened, and a passerby and the Sacramento police

helped a few slightly injured passengers out of the motorcoach. Passengers reported that

getting out of the motorcoach was difficult because it was dark, they were confused and

jammed between seats, and it was 8 feet from the windowsill to the ground. They

commented that the windows were heavy and that there was no way to hold them open. 

Twelve people were killed; the Safety Board was able to determine where nine of

them had been sitting. Five had had the aisle seats in the front level, one had had a window

seat in the third row of the front level, one had been standing in the center aisle of the rear

level, and one had had a window seat on the left side of the first row of the rear level. The

ninth was the driver.

As a result of its investigation of this crash, the Safety Board recommended that

the FHWA:

H-74-37

Establish regulations to facilitate evacuation of buses in an emergency. The

incorporation of emergency lighting systems actuated through impact and entry for

rescuers should be included in the regulation. Attention is called to the Board’s

investigation of the interstate bus accident in Baker, California, in 1968, in which it

Date and Time November 3, 1973, 9:00 p.m.

Date Report Adopted December 13, 1974

Accident No. NTSB/HAR-74-5

Location Near Sacramento, California

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 12 Fatal, 33 Nonfatal

Type of Crash Run Off Road and Collision With Bridge Column
Appendix F 111 Special Investigation Report

was recommended that “no new type buses go in to service which have not been

tested to insure that all occupants can escape rapidly.”

On February 15, 1973, NHTSA proposed a new motor vehicle safety standard

requiring that all buses have passenger seats that are stronger, higher, and less hostile on

impact. NHTSA proposed performance tests in three directions: an upward performance test

of the seat’s resistance to being torn away in a rollover, a rearward performance test of a

seat’s strength in a rear-end collision, and a forward test of a seat’s strength in a frontal

impact and its ability to deflect forward in a controlled manner that absorbs the crash energy.

In addition, NHTSA proposed to require a restraining barrier in front of each front seat to

protect passengers from being thrown into the driver, the windshield, or the door wells.4

On July 23, 1974, NHTSA rescinded its earlier proposal to promulgate a passenger

seat standard applicable to all buses and, instead, proposed issuing a standard applicable

only to school buses with a gross vehicle weight rating (GVWR) greater than 10,000 lbs.

The notice stated:

NHTSA has in fact determined that seating requirements for intercity and transit

buses are not justified, based on benefit/cost studies of present seating performance

in these buses. Injury statistics for intercity buses indicate that seating improvement

would not reduce injuries substantially. Seat-belt usage surveys in intercity buses

also indicate that a very low percentage of passengers would utilize seat belts if they

were provided .... NHTSA has conducted conventional cost-benefit studies on

school bus safety, but the normal valuation techniques evidently do not adequately

reflect general public opinion on the importance of protecting children from death or

injury. It is obvious from voluminous mail and congressional interest that society

places a much higher value on its children than a conventional cost-benefit analysis

would indicate. NHTSA has also concluded that only a small fraction of injuries

resulting from school accidents appears in motor vehicle accident statistics. For

these reasons, NHTSA is considering factors in addition to conventional costbenefit studies to justify the imposition of passenger protection requirement in

school buses.5

In its discussion of the Sacramento crash, the Safety Board stated:

If the seats had met the standards . . . withdrawn . . . on July 30, 1974, the injuries

suffered by passengers to the rear of row three would possibly have been less severe.

However, whether more passengers (who sustained fatal injuries) would have

survived in the new seats without seat belts cannot be determined. The higher

seatback proposed in the withdrawn rule would have benefited the seat-belt user,

because with seat belts, the proposed seats would probably have reduced lower and

upper leg fractures and, in conjunction with the padded seatbacks, reduced head

injuries and lacerations.

4 Federal Register, Vol. 38, No. 35, February 22, 1973, pp. 4776-4779.

5 Federal Register, Vol. 39, No. 147, July 30, 1974, pp. 27585-27589.
Appendix F 112 Special Investigation Report

CASE 10

A chartered 1967 Silver Eagle Model 01 motorcoach lost control as it descended a

steep grade on State Route 7. The motorcoach ran off the roadway into a ditch on the right,

overturned onto its right side, and began scraping along a hillside. About 120 feet from

where the motorcoach first struck the hillside, the right-side window struck a large rock

outcropping. The motorcoach then struck and mounted a 3-foot-high berm located at a

concrete culvert headwall, and the driver, who was not using the lap belt, and two

passengers were ejected through the windshield and killed. 

The berm impact redirected the motorcoach diagonally to the left across the

pavement and off the left pavement edge. Two more passengers were ejected, either

through the windshield or the shattered right front side window. After leaving the

pavement to the left, the motorcoach vaulted down into a gully and struck and either

sheared off or uprooted several trees with trunk diameters ranging from 9 to 13 inches.

Several more passengers were ejected through the windshield when the front of the

motorcoach collided with a large boulder and the motorcoach came to rest upright.

Rescuers stated that several of the passengers who remained in the motorcoach

were stacked up in the right front of the motorcoach.

Date and Time June 5, 1980, 12:47 a.m. 

Date Report Adopted January 21, 1981

Accident No. NTSB/HAR-81-1

Location Near Jasper, Arkansas

Operator Central Texas Bus Lines, Inc.

Motorcoach Passenger Injuries 19 Fatal, 13 Nonfatal

Type of Crash Loss of Control on Downgrade
Appendix F 113 Special Investigation Report

CASE 11

A 1961 GMC Model PD-4106 motorcoach carrying a church choir was traveling

south on U.S. Route 183. It was raining, and the pavement was wet. As the motorcoach

attempted to negotiate a curve to the left, the rear tires lost traction. The motorcoach

skidded across the opposing traffic lane and onto the northbound shoulder. The

motorcoach then returned to and traveled across the roadway, spun 180 degrees, struck the

side of a drainage ditch, and overturned onto its left side. 

Two fatally injured passengers, who had been sitting together in the left third row,

were ejected through a side window during the rollover and were found lying about 6 feet

apart in the drainage ditch, in front of the front of the motorcoach.

Date and Time November 16, 1980, 7:25 a.m.

Date Report Adopted July 22, 1981

Accident No. NTSB/HAR-81-4

Location Luling, Texas

Operator East Side Church of Christ

Motorcoach Passenger Injuries 2 Fatal, 35 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 114 Special Investigation Report

CASE 12

A 1959 GMC Model PD4104 intercity motorcoach on a regularly scheduled run

for commuters going from Arlington to Stafford and Fredericksburg, Virginia, was

traveling southbound in the median traffic lane of Interstate Highway 95 when it veered to

the right and ran off the roadway. The right front of the motorcoach then struck and

overrode a guardrail. After traveling 59 feet, the left front of the motorcoach struck the

north parapet of the Chopawamsic Creek Bridge. The motorcoach vaulted off the bridge

and came to rest on its right side in about 2 feet of water 25 feet below the highway.

The driver and 10 passengers were killed. All fatalities resulted from blunt trauma,

including, in some cases, massive head and thoracic injuries. There were no ejections or

drownings. 

Although numerous seat legs tore loose from the floor, most of the seats remained

in or near their precrash positions. Seat displacement was forward and slightly toward the

right side of the vehicle, indicative of secondary impact as the passengers moved forward

when the vehicle suddenly decelerated.

The least injured survivors told of moving from their seats and crouching or lying

on the floor between the seats when they recognized that a crash was imminent. The

Safety Board determined that their having left their seats helped them survive. They were

subjected to less force because some of the force was absorbed by the processes of vehicle

crush and seat displacement. 

Date and Time February 18, 1981, 4:36 p.m.

Date Report Adopted August 25, 1981

Accident No. NTSB/HAR-81-6

Location Near Triangle, Virginia

Operator D & J Transportation Company

Motorcoach Passenger Injuries 10 Fatal, 13 Nonfatal

Type of Crash Run Off Road, Collision With Bridge Parapet, 

Vault Into Creek
Appendix F 115 Special Investigation Report

CASE 13

A 1979 Blue Bird bus going eastbound on Denali Park Road ran off the right edge

of the roadway at a very slow speed and rolled to its right down a hill. Each side of the bus

had five windows, each 57 inches wide and 27 inches high. Each window included two

separate panes, one of which could be opened by sliding it rearward. The windows were

mounted in a single frame hinged at the top and latched at the bottom to the frame. By

lifting up the bottom latch, each side window could be opened and used as an emergency

exit. Each window also had a sensor that activated a buzzer to warn the driver that the

window had been opened. 

Twenty-five of the 30 passengers were ejected through the side windows before

the bus came to rest, which it did after it had rolled 2 1⁄4 times down the hillside. Five of

the ejected passengers were killed. The driver, who was restrained by a lap belt, was not

injured. A driver instructor, who was sitting in the entrance stepwell when the bus left the

roadway, was not ejected and sustained minor injuries. 

The Safety Board concluded that the absence of passenger restraints permitted

passengers to be thrown about within the vehicle and to be ejected from the vehicle as it

rolled and contributed to the severity of the injuries and to the number of fatalities.

In its discussion of the crash, the Safety Board pointed out that since 1967, it had

issued 13 recommendations to either the FHWA and/or NHTSA dealing with installing

and using passenger restraints on intercity and/or school buses. In response, NHTSA has

maintained that seat belts in such buses are not cost effective. NHTSA said that enforcing

the use of seat belts would be a major problem and that passenger containment van be

achieved through seat design and window design. 

The Safety Board noted: 

In rollover accidents, side windows open as a direct result of cross-sectional body

distortion, and major bending occurs at the side window posts (i.e. the weakest

point) and the windows break and/or open. Smaller windows, or changes in the

window locking design, will not prevent a window from opening in a rollover

environment. Reducing window size small enough to prevent ejection conflicts

with the need for a window opening large enough to be a good viewing area and

also an emergency escape route. The availability and use of individual occupant

restraints provides an answer to the problem of occupant ejection and also

prevents the occupant from being tumbled within the bus.

Date and Time June 15, 1981, 8:00 p.m.

Date Report Adopted September 29, 1981

Accident No. NTSB/HAR-81-7

Location Mt. McKinley National Park, Alaska

Operator ARA Services, Inc.

Bus Passenger Injuries 5 Fatal, 25 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 116 Special Investigation Report

CASE 14

A 1978 Silver Eagle motorcoach on a regularly scheduled run collided with the

rear of a slower tractor flatbed-semitrailer combination in the right lane of southbound

U.S. 59, about 5 miles north of Livingston, Texas. The motorcoach then veered across the

left southbound lane, crashed through a bridge guardrail, and vaulted into a creek bank 26

feet below the bridge deck.

During the crash, four of the motorcoach passengers seated left of the center aisle

were ejected through the left windows. Two of them died from massive head injuries, and

one died of a broken neck. The fourth one survived but sustained the most serious injuries

of any surviving passenger on the motorcoach, including rib fractures, a fractured left leg,

a chest wall penetration, and a bruised right lung. 

Three of the six passengers sitting on the right side of the motorcoach were fatally

injured. One was ejected, either through the windshield or the left side windows. The other

two were killed when they were thrown forward to the front of the motorcoach. One of the

surviving passengers who was seated to the right of the aisle reported that he was awake

before the crash and that he bent over in his seat and tucked his head down before the

impact with the creek bank. The driver sustained a fractured jaw, fractured ribs, chest

trauma, multiple lacerations, and abrasions to the eyes. He stated he was not wearing the

lap belt.

The Safety Board concluded that had seat belts been available and had the

passengers used them, the ejected passengers would not have been ejected and the

passengers who remained inside the motorcoach would not have been as badly hurt. Had

the driver used his seat belt, he would not have been less injured because he was sitting in

the part of the motorcoach that bore the brunt of the impact with the creek bank.

Date and Time November 30, 1983, 5:15 a.m.

Date Report Adopted July 12, 1984

Accident No. NTSB/HAR-84-4

Location Livingston, Texas

Operator Trailways Lines, Inc.

Motorcoach Passenger Injuries 6 Fatal, 5 Nonfatal

Type of Crash Collision With Rear of Tractor-Semitrailer
Appendix F 117 Special Investigation Report

CASE 15

A 1976 Silver Eagle motorcoach on a regularly scheduled run was traveling

northbound in the right lane of Interstate Highway 25 about 3 miles south of Cheyenne,

Wyoming, when it ran into the rear of a slower tractor flatbed-semitrailer loaded with

pipe. The motorcoach, it was estimated, had been going 15 to 25 mph faster than the

semitrailer. After the collision, the two vehicles remained together and traveled an

additional 429 feet before coming to rest upright in the right lane of the northbound

roadway.

The collision crushed the front lower half of the motorcoach about 3 feet rearward.

The driver’s seat and both the left and right first-row seats were torn loose from their floor

attachments.

The right front door was crushed by the collision and could not be opened. After

the motorcoach came to rest, several passengers opened the emergency side windows and

lowered themselves about 8 feet to the pavement. Rescue personnel later evacuated other

surviving passengers through these windows. 

None of the passengers were ejected. The driver, who sustained the most serious

injuries of any surviving occupant, was pinned in the wreckage and was removed through

an opening cut into the left side of the motorcoach. The passenger seated in the right firstrow seat sustained fatal head injuries when he was projected forward and struck the

semitrailer’s cargo of pipe, which intruded through the right windshield into the stepwell.

The remaining passengers sustained minor to moderate injuries. 

Date and Time July 18, 1984, 12:50 a.m.

Date Report Adopted June 25, 1985

Accident No. NTSB/HAR-85-4

Location Near Cheyenne, Wyoming

Operator Denver, Colorado Springs, and Pueblo 

Motorway, Inc.

Motorcoach Passenger Injuries 1 Fatal, 10 Nonfatal

Type of Crash Rear-End Collision With Tractor-Semitrailer
Appendix F 118 Special Investigation Report

CASE 16

A 1964 GMC Model PD4106 motorcoach co-owned and operated by three church

groups was traveling in the right northbound lane of U.S. 87 in light rain when the

motorcoach went out of control and skidded in a counterclockwise direction across the left

northbound lane and about 130 feet across the grass median. As it traveled through the

median, the motorcoach continued its counterclockwise rotation. It then slid sideways

another 144 feet over both southbound lanes and off the roadway into a field, where it

overturned 180 degrees and came to rest on its roof and facing west.

Three passengers seated next to windows on the right side of the motorcoach and

one 3-year-old boy being held in his mother’s lap next to a window seat on the left side of

the motorcoach were ejected through windows during the rollover. The four ejected

passengers sustained fatal injuries when they were pinned under the motorcoach as it

came to rest. The driver and 37 other passengers were injured. 

Date and Time July 20, 1985, 8:15 p.m.

Date Report Adopted January 21, 1987

Accident No. NTSB/HAR-87-1/SUM

Location Near Ackerly, Texas

Co-Operators Three Church Groups

Motorcoach Passenger Injuries 4 Fatal, 37 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Overturn
Appendix F 119 Special Investigation Report

CASE 17

A 1963 GMC Model PD4106 motorcoach on a regularly scheduled run was

traveling westbound on Interstate 70 in light rain at a reported speed of 55 to 60 mph when

it went out of control during a lane change and began swerving from side to side across the

travel lanes and shoulders of the westbound highway as it approached the Monocacy

River Bridge. When the motorcoach reached the bridge, it first collided with the left side

of the reinforced concrete bridge rail. The motorcoach then rotated 360 degrees

counterclockwise while rolling over. It became upright and came to rest facing westbound

with its left front side against the left bridge rail.

The driver and 5 passengers were fatally injured; 11 other passengers sustained

minor to serious injuries. During the collision sequence, the driver, who was not wearing

the lap belt, and two of the passengers who were fatally injured were ejected through the

opening made in the front of the motorcoach when it collided with the bridge rail. The

other three fatally injured passengers, as well as seven survivors who sustained serious

injuries, were ejected either through the front opening or the right side windows during the

rotation and rollover.

The Safety Board concluded that the five fatally injured passengers sustained their

fatal injuries in collisions with fixed objects outside the motorcoach. The Safety Board

believed that the chances of survival would have been better if all occupants had remained

inside the motorcoach during the accident sequence.

Date and Time August 25, 1985, 12:40 p.m.

Date Report Adopted January 22, 1987

Accident No. NTSB/HAR-87-1

Location Frederick, Maryland

Operator Baltimore Motor Motorcoach Company

Motorcoach Passenger Injuries 5 Fatal, 11 Nonfatal

Type of Crash Loss of Control and Collision With Bridge Rail
Appendix F 120 Special Investigation Report

CASE 18

A 1965 GMC Model PD-4106 motorcoach owned and operated by a church lost

control while traveling southbound and descending a 7-percent grade on Arkansas State

Route 23, a two-lane undivided highway. While traveling through a left curve, the

motorcoach traveled over the opposing lane and struck a signpost to the left of the

roadway. The motorcoach then veered across the roadway to the right, left the road, struck

another signpost, and traveled about 150 feet down a wooded hillside until the front axle

struck a large boulder. The motorcoach then rotated clockwise and overturned onto its

right side before coming to rest. 

The driver, all four passengers in the first row, and three of the four passengers in

the second row were ejected, through either the windshield or the side windows. The

driver and three of the seven passengers who were ejected were killed. Their fatal injuries

included massive head trauma, fractured or crushed skulls, a fractured cervical spine, and

an amputated left arm. The other four ejected passengers sustained minor to serious

injuries.

In addition to the eight people who were ejected from the front of the motorcoach,

a ninth person, who had the right window seat in the seventh row, was ejected through a

side window. He also sustained fatal injuries, including massive internal injuries and an

open skull fracture. 

The motorcoach had seven rows of double seats on each side of the center aisle at

the front, followed by an open area for storing choir robes. The rear had a 5-person bench,

for a total of 33 fixed passenger seats. All of the seats were occupied at the time of the

crash. Of the 24 passengers in installed seats who were not ejected, 12 sustained minor to

serious injuries, and 12 were not injured.

In addition, five additional passengers were seated on folding chairs, two in the

portion of the center aisle between the sixth and seventh rows, and three in the open area

toward the rear. Three of these passengers sustained minor injuries, and two were not

injured. Three more passengers were sitting on the floor in the open area toward the rear.

None of them were injured.

Date and Time September 13, 1985, 5:20 p.m.

Date Report Adopted January 21, 1987

Accident No. NTSB/HAR-87-1/SUM

Location Near Eureka Springs, Arkansas

Co-Operators Ozark Christian Schools, Inc.

Motorcoach Passenger Injuries 4 Fatal, 19 Nonfatal

Type of Crash Loss of Control on Downgrade, Run Off Road
Appendix F 121 Special Investigation Report

CASE 19

A chartered 1985 Neoplan Model N116-3 motorcoach was traveling southbound

on U.S. Route 395 when it went out of control while negotiating an S-curve, veered left

then right across the two-lane undivided roadway, and struck a rock retaining fence on the

right shoulder. Continuing forward, the motorcoach crossed into the northbound lane,

overturned and slid on its left side, rolled over as it traveled down an embankment, and

came to rest upright in the West Walker River.

One surviving passenger reported that he was ejected through a window before the

motorcoach entered the river. He did not recall whether the window was broken before or

during his ejection. None of the passengers interviewed could recall how they sustained

specific injuries. Many could not recall how they got out of the motorcoach. 

Rescue units found eight fatally injured passengers in the motorcoach and on the

nearby shore. Another 11 fatally injured people were found later downstream. Two of the

critically injured passengers died several days after the crash.

Although 21 fatally injured passengers were autopsied, the could not be correlated

to potential injury-causing mechanisms on the motorcoach because many passengers had

sustained secondary injuries when they were ejected during the rollover either onto the

river bank, which was laden with stones, or into the river, which was lined with sharp

rocks. Postmortem examinations determined that 7 people died from drowning and 14

died from multiple traumatic injuries.

Date and Time May 30, 1986, 10:10 a.m.

Date Report Adopted June 19, 1987

Accident No. NTSB/HAR-87-4

Location Near Walker, California

Operators Starline Sightseeing Tours, Inc.

Motorcoach Passenger Injuries 21 Fatal, 19 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Rollover Into 

West Walker River
Appendix F 122 Special Investigation Report

CASE 20

A chartered intercity 1970 Silver Eagle Model 05 bus traveling westbound on

State Route 495 veered left into the adjacent traffic lane and struck the rear of an

automobile. The bus then entered the eastbound contraflow lane and collided left-front-toleft-front with a 1972 GMC Type S8M5304A eastbound motorcoach loaded with

commuters en route to New York City. 

Of the 77 passengers in both buses, 26 sustained minor injuries, including multiple

contusions, abrasions, and superficial lacerations of the face, head, and extremities.

On the commuter motorcoach, two passengers sustained serious injuries, including

fractures of the ankle, face, fingers, hand, forearm, lower leg, and collarbone. One

passenger sustained severe injuries: a subarachnoid hemorrhage and a cerebral

concussion. One passenger, who had been in the left third-row window seat, was killed; he

sustained comminuted fractures of the skull, a transection of the base of the skull, and a

subdural hemorrhage.

All four passengers mentioned in the paragraph above had been seated in the first

three rows. At impact they had been ejected from their seats and propelled forward into

the front modesty panel, stanchion, and closed metal aisle gate. The Safety Board

concluded that lap belts would probably have reduced the severity of the injuries of two of

the three who sustained serious to severe injuries. The Safety Board also concluded that it

was harder to predict the effect lap belts would have had on the other two because the belts

would have restrained them in an area in which the charter bus intruded. Lap belts

probably would not have lessened the injuries of the passengers and drivers who sustained

minor injuries. 

Date and Time October 9, 1986, 7: 34 a.m.

Date Report Adopted October 27, 1987

Accident No. NTSB/HAR-87-6

Location North Bergen, New Jersey

Operators E. Vanderhoof and Sons, DeCamp Bus Lines

Bus Passenger Injuries 1 Fatal, 27 Nonfatal

Type of Crash Collision With Rear of Automobile and Subsequent 

Sideswipe Collision With Commuter Bus
Appendix F 123 Special Investigation Report

CASE 21

A 1977 Silver Eagle Model 05 motorcoach on a regularly scheduled run was

traveling westbound in rain on Interstate Highway 10 when it was struck head on by a

tractor-semitrailer that had been eastbound. The tractor-semitrailer had jackknifed on the

wet pavement and crossed over the 32-foot-wide grass median strip separating the

westbound and eastbound lanes of the highway. The semitrailer intruded into the

motorcoach to the third row, and the driver and all 5 passengers in the first three right rows

were fatally injured; 17 passengers sustained serious to minor injuries, and 6 passengers

were not injured.

Four of the fatally injured passengers had been in the first two rows and were

ejected through the front of the motorcoach. They were found 3 to 4 feet in front of the

motorcoach. The bodies of the driver and the passenger in the third row were pinned in the

wreckage. 

Some of the seats of the fatally injured were torn from the floor and ejected during

impact, and many of the seats in rows four through eight were removed by rescue

personnel. It therefore could not be determined which seats in rows four through eight

broke loose during the collision and which seats remained intact. The Safety Board,

therefore, could not address the use of seat belts for these particular seats.

The Safety Board concluded that the fatally injured passengers would not have

been saved by using seat belts. Although the installation and use of seat belts may have

lessened the injuries of some of the surviving passengers, in general, the level of injury of

those passengers who sustained minor or moderate injuries would probably have been the

same because they would have sustained similar injuries from contact with the seatbacks,

armrests, and side walls.

Date and Time May 4, 1987, 1:45 p.m.

Date Report Adopted February 2, 1988

Accident No. NTSB/HAR-88-1

Location Beaumont, Texas

Operator Trailways Lines, Inc.

Motorcoach Passenger Injuries 5 Fatal, 17 Nonfatal

Type of Crash Head-On Collision With Out-of-Control 

Tractor-Semitrailer
Appendix F 124 Special Investigation Report

CASE 22

A 1982 Motor Motorcoach Industries, Inc., motorcoach on a regularly scheduled

run was in the northbound “local” lanes on the New Jersey Garden State Parkway when it

ran off the road to the left and collided with a bridge rail at about a 10-degree angle. A

chain link fence was above the bridge rail; and as the motorcoach continued northbound in

contact with the bridge rail, the fencing was torn from its mountings. Parts of the bridge

rail and the fencing penetrated the windshield of the motorcoach to about the second row

of seats. After traveling about 145 feet along the bridge rail, the motorcoach overturned

onto its right side.

The driver sustained fatal injuries. The Safety Board concluded that his fatal

injuries were attributable to the intrusion of the bridge rail, the fencing, and the steering

wheel into his space. Although his body was found in the stepwell of the motorcoach and

although he had not used his lap belt, using it would not have saved him. 

The driver’s 13-year-old son, who was in the right front row, also sustained fatal

injuries. The Safety Board concluded that his fatal injuries were attributable to the

intrusion of the railing and fencing. The use of a lap belt would not have mitigated his

injuries. 

Surviving passengers reported that they left the motorcoach through the left side

emergency windows and/or the two emergency roof hatches. Thirty-two passengers

sustained minor to moderate injuries. 

The Safety Board determined that during the motorcoach’s initial collision and its

subsequent travel along the bridge rail the surviving passengers has been subjected only to

low deceleration forces that were essentially along the longitudinal axis of the

motorcoach; therefore the passengers were probably not ejected from their seats until the

motorcoach overturned. The Safety Board also determined that the motorcoach had almost

stopped when it overturned and that the lateral forces caused by the overturning were

probably the highest g forces the passengers experienced during the accident sequence.

The Safety Board determined that using lap belts would not have prevented the passengers

from striking the seats in front of them, the walls, or other passengers in adjacent seats. If

lap belts had been available and used, the passengers may have sustained different

injuries, but injuries that probably would have been no less severe.

Date and Time September 6, 1987, 5:00 a.m.

Date Report Adopted May 24, 1988

Accident No. NTSB/HAR-88-3

Location Near Middletown, New Jersey

Operator Academy Lines, Inc.

Motorcoach Passenger Injuries 1 Fatal, 32 Nonfatal

Type of Crash Run Off Road, Collision With Bridge Rail, 

and Overturn
Appendix F 125 Special Investigation Report

CASE 23

A 1982 Eagle motorcoach on a scheduled run was traveling northbound on State

Route 265 on a downgrade when it ran off the two-lane roadway to the right. The

motorcoach returned to the roadway, and the rear of the vehicle rotated off the roadway to

the left into a steep ditch. The motorcoach overturned onto its left side and came to rest

facing east with its front partially blocking the southbound lane of the roadway.

Although all the windows on the left side of the motorcoach were displaced during

the overturn, no passengers were ejected. During the overturn, the left side of the roof was

displaced to the right and pushed down; the maximum displacement was near the

longitudinal center of the motorcoach. One passenger seated in this area, in the window

seat of the left sixth row, sustained fatal injuries consisting of fractured ribs, a fractured

clavicle, and underlying lung injuries. The driver and 30 other passengers sustained minor

to serious injuries. 

Date and Time July 24, 1988, 7:35 a.m.

Accident No. DCA-88-M-H006

Location Near Camden, Alabama

Operator Colonial Trailways

Motorcoach Passenger Injuries 1 Fatal, 30 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 126 Special Investigation Report

CASE 24

A 1988 TMC Model 96A3 motorcoach on a regularly scheduled run was traveling

southbound on U.S. 281 in light rain at a driver-reported speed of about 55 mph when it

skidded broadside across the northbound traffic lane, left the roadway, and struck a dirt

embankment. After striking the embankment, the motorcoach overturned 450 degrees

while rotating 180 degrees and came to rest on its right side facing north.

The motorcoach had seven emergency exit windows on each side. All but one of

these windows, the one next to the left third row, were dislodged during the rotation and

rollover.

In addition to the driver, 22 adults and a 5-year-old girl occupied the motorcoach.

The driver, who was wearing his lap belt, sustained minor injuries. Three passengers

believed that the side windows “popped out” of the motorcoach body, and at least 14

passengers were ejected through the side window openings. Two of them sustained fatal

injuries, and the rest sustained minor to severe injuries.

One passenger, who had been sitting in the first row, reported he was ejected

through the windshield. He sustained minor injuries. Of the passengers who remained

inside the motorcoach, two were fatally injured. 

Date and Time February 18, 1989, 3:40 a.m.

Accident No. FTW-89-H-FR02

Location Near Falfurrias, Texas

Operator Valley Transit Bus Company

Motorcoach Passenger Injuries 4 Fatal, 19 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Overturn
Appendix F 127 Special Investigation Report

CASE 25

A chartered 1987 TMC Model 102A3 motorcoach was westbound on California

State Route 168 descending from the Westgard Pass when it lost control and ran off the

roadway to the left, where its front and left side struck a rock and an earthen slope. When

the left side struck the slope, a passenger sitting in the window seat on the left side in the

seventh row was ejected and killed. All the windows on the left side were broken as a

result of the impact with the slope, and the impact re-directed the motorcoach to the right.

It crossed over the two-lane undivided roadway, traveled down a 7-foot embankment, and

came to rest upright on the north roadside.

The driver reported that the ejected passenger was standing at the time of this

impact. Another passenger seated in the left aisle seat in row two was critically injured and

died 4 months later.6

 Nine other passengers stated they were ejected through either the side

windows or the windshield. The rest of the surviving passengers sustained minor to

critical injuries. 

Date and Time May 18, 1990, 3:40 p.m.

Accident No. FTW-90-F-H004

Location Big Pine, California

Operator Southwest Charter Lines

Motorcoach Passenger Injuries 2 Fatal, 43 Nonfatal

Type of Crash Loss of Control and Run Off Road

6 Not considered a fatality on the FARS system.
Appendix F 128 Special Investigation Report

CASE 26

A 1990 Van Hool Model T-800 chartered motorcoach was traveling southbound

on Pennsylvania State Route 209 descending a 5.4-percent grade when it swerved to the

right as the driver reached to retrieve a thermos bottle that had rolled forward from the

passenger seating area. A passenger in the right first row stated that after the motorcoach

swerved to the right, the driver quickly sat up and turned the steering wheel hard to the

left. The motorcoach veered left across the northbound lane of the two-lane roadway,

crashed through a guard rail, and obliquely descended a 39-degree side slope, coming to

rest upright and lodged between several trees 180 feet from where it left the roadway.

The driver stated that just before the motorcoach came to a stop, a passenger flew

past him on his right and through the windshield. A passenger sitting in the first seat left of

the aisle stated that as she reached down to pick up the thermos she was propelled forward,

to the right, and into the aisle. The man seated opposite her on the right side stood up and

pushed her back into her seat. The next thing she remembered was that she was lodged in

the left windshield frame, half in and half out of the motorcoach, and that she then looked

down in front of her and saw the man who had pushed her back into her seat lying on the

ground outside the motorcoach. He had fatal injuries.

The driver’s seat, the tour guide’s seat in the stepwell, and the four seats in the first

row had lap belts. Although the driver reported he was using his lap belt, several

passengers reported that when the motorcoach came to rest he was in the stepwell. None

of the passengers in the first row had used their belts. 

Three additional passengers in the rear of the motorcoach were also ejected

through the left rear side window. Immediately before the crash, one of them was kneeling

on the aisle seat in front of the right-side restroom; another was standing in the aisle next

to the last row in front of the restroom; and the third was seated in the window seat of the

last row on the left side. One of these ejected passengers was killed, another sustained

severe injuries, and the third sustained minor injuries. The driver and the remaining

passengers sustained minor to serious injuries.

Date and Time February 2, 1991, 10:00 a.m.

Accident No. NRH-91-FH-005

Location Joliett, Pennsylvania

Operator Leonard Lines, Inc.

Motorcoach Passenger Injuries 2 Fatal, 44 Nonfatal

Type of Crash Loss of Control and Run Off Road
Appendix F 129 Special Investigation Report

CASE 27

A 1982 TMC Model MC-9 motorcoach on a regularly scheduled run was traveling

eastbound on the Pennsylvania Turnpike when it ran off the right side of the roadway,

traveled down a 100-foot embankment, and overturned onto its right side. 

No one was ejected. A passenger seated in the second window seat on the right

side sustained fatal blunt force injuries, including multiple rib fractures, a fractured

sternum, and lacerations of the heart. The driver and 14 other passengers sustained broken

bones, cuts, bruises, and abrasions. 

Date and Time June 26, 1991, 1:50 p.m.

Date Adopted March 13, 1992

Accident No. NTSB/HAR-92-1

Location Near Donegal, Pennsylvania

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 1 Fatal, 14 Nonfatal

Type of Crash Run Off Road
Appendix F 130 Special Investigation Report

CASE 28

A chartered 1988 MCI motorcoach was traveling eastbound on the snow-covered

Indiana Toll Road (Interstate Highway 80). The driver stated that he overtook a slower

vehicle and tried to pass it on the left. He stated the vehicle ahead then moved to the left

and he braked. Witnesses, however, stated there were no other vehicles immediately ahead

of the motorcoach.

The motorcoach went out of control, rotated clockwise about 180 degrees, ran off

the right side of the eastbound roadway, and slid down a 19-percent-grade embankment at

an oblique angle. As it was descending the embankment, the motorcoach’s left rear wheels

struck a concrete culvert, and the motorcoach overturned onto its roof. The motorcoach

came to rest inverted facing west at the base of the embankment, about 100 feet from

where it left the roadway. 

Two women were ejected through the windows next to them. Each woman had

been sitting in a window seat on the left side of the motorcoach. Their seats, one in the 10th

row and one in the 12th row, were among the rearmost seats on the motorcoach. Rescue

personnel stated that both women were found under the motorcoach--one under the rear

and one under the sixth window pillar on the left side. Both were killed; the cause of death

was determined to be traumatic asphyxia. One of the other passengers sustained serious

injuries, and the driver and the remaining passengers sustained minor to moderate injuries.

Date and Time January 24, 1992, 12:15 a.m.

Accident No. NRH-92-F-H003

Location Near South Bend, Indiana

Operator United Limo, Inc.

Motorcoach Passenger Injuries 2 Fatal, 34 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 131 Special Investigation Report

CASE 29

A chartered 1990 MCI Model 10203 motorcoach was traveling southbound on

Interstate 87 when it went out of control, ran off the right side of the roadway, and struck a

cable barrier. After striking the barrier, the motorcoach returned to the roadway, rotated

180 degrees while crossing both southbound travel lanes, flipped over the median cable

barrier, overturned 360 degrees, and came to rest upright, facing north, at the bottom of a

steep embankment. 

Both windshields and the destination sign panel broke out of the motorcoach

during the crash sequence and were found at the top of the embankment. The rollover

pushed the entire roof 2 to 5 inches downward. The passenger compartment had seven

windows on each side; five windows were broken on the right side, and six windows were

broken on the left side.

Six of the passengers were ejected through the side windows during the rollover.

Two of them sustained fatal injuries.

Date and Time April 11, 1992, 4:45 p.m.

Accident No. DCA-92-M-H002

Location Near Schroon Lake, New York

Operator Grey Line New York Tours

Motorcoach Passenger Injuries 2 Fatal, 29 Nonfatal

Type of Crash Loss of Control and Overturn
Appendix F 132 Special Investigation Report

CASE 30

A 1972 MCI Model MC-7 chartered motorcoach lost control as it descended a

steep grade on Sussex County Road 515, struck a car, overturned on its right side, slid and

spun on its side, became upright, and struck another car before coming to rest. A fire

ensued, burning the motorcoach and the second car, but no motorcoach passengers died in

the fire.

After the motorcoach overturned and while it was sliding and spinning, 12

passengers in the first three rows were ejected through the windshield. Six of them

sustained fatal injuries, including skull fractures, brain injuries, multiple internal injuries,

and fractured extremities. The driver and the other 42 passengers sustained minor to

critical injuries.

Date and Time July 26, 1992, 11:10 a.m.

Date Report Adopted June 23, 1993

Accident No. NTSB/HAR-93-2

Location Vernon, New Jersey

Operator Sensational Golden Sons Bus Service, Inc.

Motorcoach Passenger Injuries 6 Fatal, 37 Nonfatal

Type of Crash Loss of Control on Downgrade
Appendix F 133 Special Investigation Report

CASE 31

A chartered 1987 Prevost motorcoach was traveling southbound on U.S. Highway

60 when it collided left-front-to-left-front with an automobile. The motorcoach then left

the roadway to the right, skidded down a steep embankment, rolled onto its right side, and

slid an additional 9 feet before coming to rest.

None of the motorcoach passengers were ejected. The driver and many of the

passengers stated that the motorcoach had almost stopped when it rolled over. Most of the

passengers stated that they had received their injuries from falling across the motorcoach

and/or from having other passengers fall on top of them. Most of the 12 seriously injured

passengers sustained arm, vertebra, and multiple rib fractures complicated by

pneumothoraces. Several passengers sustained closed head injuries, including one injury

that resulted in blindness. The fatally injured passenger was not autopsied, but the local

county coroner believed she had sustained a crushed chest and a broken neck.

Date and Time June 26, 1993, 4:40 p.m.

Accident No. CRH-93-F-H040

Location Near Springfield, Missouri

Operator Cardinal Charters and Tours, Inc.

Motorcoach Passenger Injuries 1 Fatal, 46 Nonfatal

Type of Crash Collision With Automobile, Run Off Road, 

and Overturn
Appendix F 134 Special Investigation Report

CASE 32

A 1986 MCI Model 102A3 motorcoach on a regularly scheduled run was traveling

eastbound on Interstate Highway 10 when it left the roadway to the right. The driver

overcorrected, steering the motorcoach sharply to the left. The motorcoach then crossed

both eastbound lanes and entered the median shoulder. The driver steered sharply to the

right, causing the motorcoach to slide sideways and overturn onto its left side. It slid on its

left side for about 140 feet and came to rest facing southeast and blocking both eastbound

lanes.

Seven windows on each side of the motorcoach were emergency exit windows that

were hinged at the top and latched at the bottom. The rollover displaced the roof of the

motorcoach about 7 inches to the right; the left rear upper corner of the motorcoach

sustained the most severe damage. Both windshields, the driver’s left side window, and

the rearmost left side window were broken. Four other windows on the left side were

found open.

Three of the five most seriously injured passengers were sitting at the left rear of

the motorcoach:

A 40-year-old man seated next to the left window in the 12th (rearmost) row

sustained lacerations and contusions; both hands were severed. Later, doctors had to

amputate both forearms.

A 15-year-old boy seated next to the left window in the 11th row sustained

abrasions and contusions to the face and chest, a severe wound in the right hand, and a

severed left arm.

A 61-year-old woman seated next to the left window in the 10th row sustained

fractured ribs and pulmonary contusions.

Safety Board investigators determined that the left window spanning rows 11 and

12 opened before the left side of the motorcoach struck the roadway. During the rollover

the man who would lose his hands was partially ejected; his hands and possibly his

forearms were outside the window. As a result, the edge of the side of the motorcoach

severed the man’s hands when the motorcoach overturned and slid.

One of the other two most seriously injured passengers was a 58-year-old woman

sitting at the window in the right fourth row. The aisle seat next to her was unoccupied.

She sustained a ruptured spleen, cracked vertebrae, and a broken shoulder. The other most

seriously injured passenger was sitting in the aisle seat in the 11th row on the right side.

She sustained a broken neck and a fractured right hand. The driver and 28 of the

passengers sustained minor to moderate injuries. Six of the passengers were not injured.

Date and Time September 10, 1993, 7:10 a.m.

Accident No. WRH-93-F-H054

Location Near Phoenix, Arizona

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 0 Fatal, 33 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 135 Special Investigation Report

CASE 33

A bus consisting of a National Motorcoach, Inc., body mounted on a 1985 Ford E350 chassis was traveling westbound on Camden County Road 536 Spur at a witnessestimated speed of 30 to 35 mph when it collided head on with an eastbound truck that had

crossed the center line of the undivided roadway.

The bus was manufactured with a GVWR of 11,000 pounds by Ford and 11,400

pounds by the second-stage manufacturer, National Coach, Inc. The bus had a wheelchair

lift behind its door. Three rows of forward-facing two-passenger seats were behind the

wheelchair lift. Behind the driver’s seat was a two-passenger center-facing seat followed

by three rows of forward-facing two-passenger seats. The bus could seat 14 passengers.

Each passenger seat had two vertical stanchions that were welded to brackets,

forming seat legs shaped like an inverted “T.” The seat legs were attached to the vehicle’s

floor by two bolts through the brackets. Each of the passenger seats had a lap belt. One

end of each lap belt was bolted to a seat leg stanchion, and the other end was bolted to

center of the seatframe below the cushion. All of the seats were occupied at the time of the

collision, and it was reported that all of the passengers were using the lap belts.

At impact the stanchion-to-bracket welds of the right front, right center, and left

center seats failed completely, and emergency responders reported that these seats with

their belted occupants were found piled up at the right near the entrance door. The two

passengers in the right front seat sustained fatal injuries, and the four passengers in the

right center and left center seats sustained minor to serious injuries.

The stanchion-to-bracket welds for the left front and for both the left and right rear

seats partially failed at the weld area connecting the aft portion of the stanchion to the

floor bracket, and these seats were found tilted forward enough for the front edges of the

seat cushions to touch the floor.

One of the passengers in the left front seat died the day after the crash, and the

other passenger in this seat died 3 months later (December 21, 1993) from injuries

sustained in the crash. The passengers in the left and right rear seats sustained moderate to

serious injuries. 

The stanchion-to-bracket welds for the center-facing seat did not fail. The

passenger seated immediately behind the driver died 2 days after the crash, and the other

passenger in this seat died 3 months after the crash (December 25, 1993). The driver died

of his injuries a month after the crash (October 13, 1993).

Date and Time September 17, 1993, 2:08 p.m.

Accident No. SRH-93-F-H042

Location Winslow Township, New Jersey

Operator Senior Care Centers of America, Inc.

Bus Passenger Injuries 6 Fatal, 8 Nonfatal

Type of Crash Head-On Collision With Truck
Appendix F 136 Special Investigation Report

CASE 34

A 1994 MCI model 102DL3 motorcoach on a regularly scheduled run was

traveling southbound on Interstate Highway 25 on icy pavement when it went out of

control, left the roadway, rotated 180 degrees, and rolled over onto its left side.

Each side of the passenger area had eight emergency exit windows that were made

of shatterproof laminated glass. During the rollover, seven windows on the left were

dislodged from their frames. Although the windows cracked when they separated from

their frames, each remained in one piece. The windows on the right side of the motorcoach

remained intact.

The driver was wearing his lap belt at the time of the crash and was not injured.

During the rollover, two passengers were ejected through the left side windows and pinned

under the motorcoach by the support posts between the windows. One of these passengers

sustained fatal injuries, and the other sustained minor injuries. Rescue personnel removed

a passenger from the motorcoach who was in the lavatory at the time of the crash. All of

the eight other passengers left the motorcoach through the two emergency escape hatches

on the roof. 

Date and Time January 29, 1994, 9:20 p.m.

Crash No. WRH-94-F-HB02

Location Near Pueblo, Colorado

Operator El Paso-Los Angeles Limousine Express, Inc.

Motorcoach Passenger Injuries 1 Fatal, 8 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Overturn
Appendix F 137 Special Investigation Report

CASE 35

On April 23, 1994, about 4:40 p.m., a vehicle consisting of a 21-passenger Goshen

Bus body mounted on a 1992 Ford chassis with a GVWR of 13,500 pounds was traveling

southbound on Interstate Highway 87 near Chestertown, New York. The bus ran off the

left side of the southbound roadway, rolled over 450 degrees, and came to rest on its left

side facing west. The bus was in the median separating the north- and southbound lanes

and was about 300 feet south of the point where it had left the roadway. Tire marks

indicate that the bus left the roadway at a 7-degree left angle. 

Each side of the bus had four windows that were each 3 feet wide and 3 feet high.

Although the windows on the right side remained intact during the overturn, all four on the

left side were broken out during the overturn. Based on the location of the glazing from

the left windows, which was found about 80 feet north of the bus’ final position, the left

windows separated from the bus when it first rolled over 90 degrees to the left. 

At the time of the crash, the bus was transporting 21 passengers; they were

returning to New York City after visiting inmates at two penal institutions in Raybrook,

New York. It is estimated that as many as 14 of the passengers were completely or

partially ejected through the left windows during the rollover. One of the passengers who

were completely ejected was killed, and the surviving passengers who were completely

ejected sustained the most serious injuries.

Date and Time April 23, 1994, 4:40 p.m.

Accident No. DCA-94-MH-005

Location Near Chestertown, New York

Operator Best Transit Corporation

Bus Passenger Injuries 1 Fatal, 20 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 138 Special Investigation Report

CASE 36

A chartered 1990 Van Hool Model T-800 motorcoach lost control as it descended a

steep grade on eastbound Warren County (New York) Route 11 approaching a “T”

intersection with New York State Route 9N (SR 9N). Although the driver attempted to

make a right turn at the intersection, the motorcoach side-slipped across both travel lanes

of SR 9N, crashed through a box beam guardrail, plunged 150 feet down a steep

embankment, overturned, and came to rest on its left side.

During the crash sequence the windshield separated from the motorcoach, and the

left side windows shattered. The driver’s seat, the tour director’s seat (in the step well), the

first-row seats on both sides of the center aisle, and the center position of the bench seat at

the rear had lap belts. The driver stated he was restrained by his lap belt. The passenger in

the tour director’s seat was not using the lap belt and was thrown into the step well. The

front-row passengers on the left and a passenger who was standing in the center aisle near

the first row were not restrained and were ejected through the windshield opening. The

standee was killed. One passenger from the front row on the right was thrown forward into

the entrance well.

Other passengers seated behind the first row were partially or completely ejected

through the window openings on the left side. 

A passenger in a fourth-row seat left of the center aisle was pinned under a tree

branch; consequently she could not move her upper body. Her upper body, which was

outside the motorcoach, was facing the window; and the lower part of her body was still

inside the motorcoach. She sustained a fractured clavicle and chest and shoulder

contusions.

A passenger in the fourth right row reported first being thrown around inside the

motorcoach and then being ejected through a window. This passenger sustained eight

fractured ribs and a fractured vertebra.

A passenger in the right sixth row was thrown out a side window, and a portion of

the roof-mounted air conditioner landed on top of her. She sustained fractures of the spinal

column, paraplegia, and chest trauma.

A passenger seated in the right eighth row was partially ejected and pinned under

the motorcoach on her back with her knees against her chest and her feet dangling over her

Date and Time July 23, 1995, 2:15 p.m.

Accident No. NRH-95-MH-012

Location Near Bolton Landing, New York

Operator Bridges and Bridges Charter and Transit 

Service, Inc.

Motorcoach Passenger Injuries 1 Fatal, 30 Nonfatal

Type of Crash Loss of Control, Run Off Road, and Overturn
Appendix F 139 Special Investigation Report

face. While she was pinned, EMTs gave her oxygen, suction, and IVs and monitored her

heart. After the nonambulatory passengers were removed from the motorcoach, it was

lifted off her with airbags. She was extricated about 1 to 1 1⁄4 hours after emergency

responders arrived at the scene and was the last person evacuated. She sustained

abdominal trauma and abrasions.

A passenger in the left ninth row was thrown through a side window, and her upper

torso was pinned under the motorcoach. She sustained multiple traumas to the chest, head,

and lower extremities.

A postcrash inspection of the lap belts of the left front row indicated that both

buckles were missing. A postcrash inspection of the lap belts in the right front row

indicated that the boots, or the covers for the tongues, were missing and that the websensitive retractors were jammed due to lack of clearance with the seat cushion. The lap

belts of the four seats were, therefore. not functional before the crash.
Appendix F 140 Special Investigation Report

CASE 37

A chartered 1989 Eagle International Model 20 motorcoach exited from eastbound

Interstate Highway 70 onto the Keystone Avenue exit ramp at an estimated speed of about

55 mph. The exit had an advisory maximum safe speed of 25 mph. The motorcoach yawed

off the exit ramp, overturned onto its left side, and slid 50 feet.

Because the air conditioning on the motorcoach did not work, the side windows

had been opened. Two passengers, a 9-year-old boy and a 30-year-old woman who was 6

months pregnant, were partially ejected through the side windows next to their seats and

died of massive head injuries. The driver and the 38 remaining passengers sustained minor

to serious injuries. 

Date and Time October 14, 1995, 12:33 a.m.

Accident No. CRH-96-F-H001

Location Indianapolis, Indiana

Operator Hammond Yellow Coach Lines (legal name of 

carrier may have been “Hammond Yellow 

and Checker Cab, Inc.”) 

Motorcoach Passenger Injuries 2 Fatal, 38 Nonfatal

Type of Crash Run Off Road and Overturn
Appendix F 141 Special Investigation Report

CASE 38

A chartered 1978 Prevost motorcoach was traveling southbound on Interstate

Highway 25, 10 miles north of Albuquerque, New Mexico, when it drifted off the

roadway to the right, rode up and over a guardrail, and struck the top 18 inches of a

cement wall protecting a highway underpass. The impact forced the floor of the

motorcoach about 2 feet upward at about the third row.

The impact ejected a male passenger from his first-row aisle seat, and his body hit

and collapsed the right modesty panel separating the passenger compartment from the step

well. He then continued forward and hit the right windshield, dislodging the glazing. Both

he and the glazing fell about 15 feet to the surface of the dirt roadway passing underneath

the Interstate Highway. He sustained serious injuries.

A woman seated in the right front window seat was also thrown from her seat and

followed the man through the opening he had made in the windshield. Not being slowed

by either the modesty panel or the windshield glazing, she was not only ejected, but

thrown across the entire width of the roadway passing underneath the Interstate. She

sustained fatal injuries. 

The three passengers in the second and third rows on the right side were also

ejected through the right windshield. They sustained moderate injuries.

The remaining 31 passengers sustained minor injuries. Several of the passengers

broke the seatbacks of the seats in front of them as a result of the impact. The driver, who

was not ejected, was not wearing his seat belt.

Date and Time June 6, 1997, 6:30 p.m.

Accident No. WRH-97-F-H005

Location Near Albuquerque, New Mexico

Operator Red Rock Limousine, Inc.

Motorcoach Passenger Injuries 1 Fatal, 35 Nonfatal

Type of Crash Run Off Road 
Appendix F 142 Special Investigation Report

CASE 39

A chartered 1985 TMC motorcoach was traveling northbound on Interstate

Highway 95 when it left the roadway to the right, went through a fence, and vaulted over

and through small trees into the Nottoway River, coming to rest on its left side in about 4

feet of water.

The fall into the river crushed the right front of the motorcoach back to the right

front modesty panel, and a passenger who had been seated in the right first row was

ejected. The passenger sustained visible head trauma and was found drowned near the

driver’s seat. 

The impact pinned the driver’s legs in the wreckage at the left front of the

motorcoach, but his head was above the water; he was extricated by emergency

responders and survived with serious injuries. The remaining 31 passengers, who

sustained minor or no injuries, escaped from the partially submerged motorcoach through

the windows on the right side.

Date and Time July 29, 1997, 7:15 a.m.

Accident No. NRH-97-M-H010

Location Near Stony Creek, Virginia

Operator Rite-Way Transportation, Inc.

Motorcoach Passenger Injuries 1 Fatal, 32 Nonfatal

Type of Crash Run Off Road Into River
Appendix F 143 Special Investigation Report

CASE 40

A 1993 MCI motorcoach on a scheduled run was traveling southbound on State

Highway 226 when it failed to stop at a T-intersection stop sign controlling the entrance to

U.S. Highway 49. The motorcoach swerved to the right as it entered the intersection,

traveled across both lanes of U.S. 49, left the roadway, traveled southwest 26 feet through

a ditch, and struck an earthen levee surrounding a rice field. The motorcoach then traveled

up and over the levee and continued southwest another 100 feet, where it came to rest

upright in the rice field. There were approximately 110 feet of tire marks through the

intersection to the point where the motorcoach left the pavement. 

The left front bumper and fender of the motorcoach buckled from striking the

levee. The rest of the exterior damage, including superficial damage to the motorcoach’s

left side, was minor. The interior also sustained only minor damage.

Both of the motorcoach’s windshields were found southeast of where the

motorcoach came to rest. A passenger seated in the right front seat of the motorcoach

before the crash was ejected through the windshield and was found in the rice field

approximately 22 feet in front of the final position of the motorcoach. He sustained serious

injuries and died after being transported to a local hospital. An inspection of the interior of

the motorcoach disclosed no damage to the components along this passenger’s ejection

path. 

The driver, who was using a lap belt, sustained minor injuries. Six other

passengers also sustained minor injuries. One them, who was seated in an aisle seat on the

right side of the motorcoach, reported that as result of the crash she was thrown down the

center aisle to the front of the motorcoach. Two passengers were not injured.

Date and Time September 13, 1997, 00:05 a.m.

Accident No. WRH-97-F-H013

Location Jonesboro, Arkansas

Operator Greyhound Lines, Inc.

Motorcoach Passenger Injuries 1 Fatal, 6 Nonfatal

Type of Crash Run Off Road 
144 Special Investigation Report

Acronyms and Abbreviations

ABA American Bus Association

AIS Abbreviated Injury Scale

ATB Articulated Total Body

BMCS Bureau of Motor Carrier Safety

CFR Code of Federal Regulations

CG center of gravity

Commission European Commission

DEKRA Deutscher Kraftfahrzeug-Überwachungs Verein

DOT Department of Transportation

EDGEN Engineering Dynamics Corporation General Analysis Tool

EDSMAC4 Engineering Dynamics Corporation Simulation of Automobile 

Collisions

EDVDS Engineering Dynamics Corporation Vehicle Dynamics Simulator

EDVSM Engineering Dynamics Corporation Vehicle Simulation Model

EU European Union

FARS Fatality Analysis Reporting System

FHWA Federal Highway Administration

FMCSR Federal Motor Carrier Safety Regulations

FMVSS Federal Motor Vehicle Safety Standards

GATB Graphical Articulated Total Body

GES General Estimates System

GVWR gross vehicle weight rating

HVE Human Vehicle Environment

MADYMO MAthematical DYnamical MOdels

MCI Motor Coach Industries

MMUCC Model Minimum Uniform Crash Criteria

m-smac McHenry Simulation Model of Automobile Collisions

NAGHSR National Association of Governors’ Highway Safety 

Representatives

NHTSA National Highway Traffic Safety Administration

NPRM notice of proposed rulemaking

NSC National Safety Council

UBOA United Bus Owners of America

UNECE United Nations Economic Commission for Europe

UNECER United Nations Economic Commission for Europe Regulation

VIN vehicle identification number