() ' ' 

, 

PB83-917004 

NATIONAL 

...------. TRANSPORTATION 

SAFETY 

BOARD 

WASHINGTON, D.C. 20594 -

SAFETY REPORT 

GENERAL AVIATION CRASHWORTHINESS 

PROJECT, PHASE ONE 

NTSB/SR-83/01 

UNITED STATES GOVERNMENT 
,. 

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TECHNICAL REPORT DOCUMENTATION PAGE 

1. Report No. 

NTSB/SR-83/_01 I 2.Government Accession No. 

PB83-917004 

4. Title and Subtitle Safety Report: General 

Aviation Crashworthiness Project, Phase One. 

]. Author{s} 

9. Performing Organization Name ~nd Address 

National Transportation Safety Board 

Bureau of Technology r 

Washington, D.C. 20594 

12.Sponsorlng Agency Name and Address 

NATIONAL TRANSPORTATION SAFETY BOARD 

Washington, D. C. 20594 

15.Supplementary Notes 

16.Abstract 

3~Recipient's Catalog No. 

5.Report Date 

June 27, 1983 

&.Performing Organization 

Code 

ij.Performing Organization 

Report No. 

IO.Work Unit No. 

3741 

J.J.Contract or Grant No. 

13.Type of Report and 

Period Covered 

Safety Report 

1972 -1981 

14.Sponsoring Agency Code 

Between 1972 and 1981, more than 21,000, or 25 percent, of the occupants of 

general aviation aircraft involved in accidents were killed or seriously injured. The standards for 

occupant protection in general aviation aircraft have remained essentially unchanged for about 

the last 30 years. During this period, however, there have been major advances in 

crashworthiness technology. With the application of existing crashworthiness technology, it is 

not unreasonable to expect a substantial reduction in the over 21,000 deaths and serious injuries. 

The general aviation industry recently has expressed a desire to more fully apply 

crashworthiness technology to aircraft. However, reS;l-world data on the reaction of the 

airplane, its components, and the occupants to a crash, are needed to develop design criteria. As 

part of its ongoing work in the area of general aviation crashworthiness, the Safety Board has 

undertaken a special program of investigation that will provide the real-world data necessary to 

establish an envelope of typical general aviation accident impact deceleration loads and to 

describe crash scenarios for a range of general aviation accidents for which design for passenger 

survivability is feasible. 

This report, the first of a projected series, explains the Safety Board's 

crash worthiness program, its objective, and its goals. It presents a description of . the 

crashworthiness analysis methodology used, demonstrates its validity, and provides an example 

demonstrating its application. · 

17. Key Words 

General aviation accidents; crashworthiness; 

crash loads; accident investigation; accident 

investigation methodology; crash pulse; 

kinematics. 

19.Security Classification 

(of this report) 

UNCLASSIFIED 

NTSB Form 1765.2 (Rev. 9/74) 

20.Security Classification 

(of this page) 

UNCLASSIFIED 

HLOistribution Statement 

This document is available 

to the public through the 

National Technical 

Information Service 

Springfield, Virginia 22161 

21.No. of Pages 22.Price 

94 
INTRODUCTION • • • • • • • • • 

CRASHWORTHINESS PROGRAM • 

Program Objective and Goals . 

CONTENTS 

Data Requirements. . • • • 

ANAL Y81S METHOD • • • • • 

Impact Severity • • . • • 

Visualization . • • . • • 

Pulse Shape Development . 

METHOD VERIFICATION • 

Pitch Attitude. • • • 

Crash Pulse • • • . • 

Analysis Summaries 

1 

3 

3 

4 

5 

5 

6 

11 

18 

18 

24 

25 

APPLICATION OF ANALY81S OF NTSB ACCIDENT INVESTIGATION DATA • • 37 

CONCLUDING REMARKS • • • • • • • • • • • • • • . • • • • • • 45 

GLOSSARY OF TERMS USED IN THE CRASHWORTHINHSS PROGRAM 

APPEND~ . . . . . . . . . . . . . . . . . . . . . . . . . 

Appendix A--NTSB General Aviation Crashworthiness Recommendations 

and FAA Responses • • • . • • • • • • • • • • • • • • 

Appendix B--NTSB Expanded Accident/Incident Report 

(NTSB Form 6120.4) • • • • • . . • • • • • . • • • • • . • • • • 

Appendix C--Computer Program for Crashworthiness Analysis • 

Appendix D--Crashworthiness Program Investigations to Date • 

ii 

48 

57 

57 

65 

84 

92 

t . ··, 

~.;.j I' F 
NATIONAL TRANSPORTATION SAFETY BOARD 

WASHINGTON, D.C. 20594 

SAFETY REPORT: 

GENERAL AVIATION 

CRASHWORTHINESS PROJECT, PHASE ONE 

Adopted: June 27, 1983 

INTRODUCTION 

Between 1972 and 1981, 41,319 general aviation accidents of all types !/occurred. 

Of the over 83,000 occupants of these aircraft, more than 21,000, or 25 percent, were 

killed or seriously injured. About 34 percent, or more than 14,000 of the accidents were 

classified as relatively nonsevere !/ and resulted in fatal or serious injuries to 1,073 

· occupants. The accidents which were classified as relatively severe comprised about 

59 percent, or over 24,000, and resulted in fatal injuries to over 11,000 occupants and 

serious injuries to almost 6,000 occupants. 

Since its inception, the Safety Board has been concerned about the limited emphasis 

which has been placed on improving the quality of occupant protection in general aviation 

aircraft. Since 1970, the Safety Board has issued 23 safety recommendations (see 

appendix A) and has conducted two special studies .Y which addressed general aviation 

crashworthiness 3/ and occupant protection. 

The standards for occupant protection in general aviation aircraft have remained 

essentially unchanged for about the last 30 years. During this period, there have been 

major advances in crashworthiness technology, many of which resulted from 

government/industry research and investigative projects conducted in the late 1950's and 

the early 1960's. The projects, which included full scale crash testing of a variety of 

aircraft, were performed in all areas of crashworthiness, including postcrash fire, 

seats/restraints, cockpit/cabin environment, and the crash acceleration environment. 

Much of the information obtained from the projects, as well as information from 

earlier studies, was incorporated into the first and subsequent editions of the Aircraft 

Crash Survival Design Guide~/ and first released to the public by the Army in 1967. 

!/ To facilitate further analysis, the accident types were divided into two accident 

categories- relatively severe and relatively nonsevere accidents. The severe accidents 

included collisions with the ground or other objects, stall/spin accidents, and some · 

accidents following engine failure or malfunction. Typical of the nonsevere accidents 

were ground loops, hard landings, gear-up landings, nose-overs, or under/overshoots. Not 

included were accidents such as propeller strikes, inflight structural separations, and 

midair collisions. 

!I Special Study, 11General Aviation Accidents: Postcrash Fires and How To Prevent Or 

Control Them" (NTSB-AAS-80-2); Safety Report, "The Status of General Aviation Aircraft 

Crashworthiness" (NTSB-8R-80-2). 

~I Crashworthiness refers to the capability of a vehicle to protect its occupants during a 

crash. 

!/ Aircraft Crash Survival Design Guide, USARTL-TR-79-22, Applied Technology 

Laboratory, U.S. Army Research and Technology Laboratories (AVRADCOM), Fort Eustis, 

Virginia, 1980. 
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Since that time the document has been revised periodically to reflect the changing 

technology in crash survivability. However, in spite of the availability of the information, 

only the Army has chosen to apply it fully to their helicopter design standards. 

The Safety Board believes that had the existing crashworthiness technology been 

applied, most of the 1,073 deaths and serious injuries which occurred in the nonsevere 

accidents would have been avoided. Although the percent reduction in the number of 

deaths and serious injuries in .the more severe accidents would not be as great as in the 

nonsevere accidents, it is still not unreasonable to expect that there would have been 

substantially fewer than the 17,000 deaths and serious injuries which did occur in these 

accidents. 

The Federal Aviation Administration (FAA) has not upgraded existing occupant 

protection standards or incorporated new standards into the existing regulations for civil 

airplanes in a timely manner. This inaction has influenced the general aviation industry, 

which has not taken full advantage of existing crashworthiness technology to upgrade 

occupant protection in newly manufactured airplanes of current design or in the design of 

new airplanes. 

In the last several years, interest regarding general aviation crashworthiness has 

gained exposure from sources other than the FAA and NTSB. In February 1983, a 

Government/industry group, including representatives of the General Aviation 

Manufacturers Association (GAMA), met at the National Aeronautics and Space 

Administration's (NASA) Langley, Virginia, facility to study small airplane stall speed. 

The findings of the group regarding crashworthiness included: (1) the mandatory 

availability and use of upper torso restraints in small aircraft could provide an immediate 

• ' 

' 

improvement in crash worthiness; (2) there currently is an adequate body of knowledge for ., , the issuance of initial rules pertaining to structural crashworthiness for small airplanes; 

and (3) additional research is needed to define a crash scenario representative of 

survivable accidents on which crashworthiness performance standards can be based. 

Also in February 1983, the General Aviation Safety Panel (GASP), an industry task 

force which was convened at· the invitation of the FAA, issued a position paper containing 

several recommendations dealing with crashworthiness. Like the Government/industry 

group, the task force recommended mandatory installation and use of should,er harnesses 

as soon as practicable. It also recommended that the development of new crashworthiness 

design standards be expedited. One of the immediate goals for this recommendation was 

to "provide a means for collecting meaningful accident data on the effectiveness of seat 

restraints and harnesses. Such "real-world" data would be compared with experimental 

results in order to provide a broader basis for creating design criteria." 

The Safety Board is in a unique position to collect and analyze "real-world" data on 

crash forces and the effectiveness of seats/restraints, as well as to help to define realistic 

general aviation crash scenarios. To assist the manufacturers and FAA in defining 

reasonable design crashworthiness objectives, the Safety Board has undertaken a special 

program of investigation that will provide the 11real-world" data necessary to establish an 

envelope of typical general aviation accident impact deceleration loads and to describe 

crash scenarios for a range of general aviation accidents in which design for passenger 

survivability is feasible. If specific safety problems are observed in the course of these 

investigations which warrant immediate attention, they will be addressed immediately in 

separate safety recommendations. The data regarding occupant protection/crashworthiness also will assist the Safety Board in assessing the continuing validity of its past safety • .' ~ 
-3-

recommendations and in developing new recommendations. This initial report explains the 

crashworthiness program, its objective, and its goals. It presents a . description of the 

crashworthiness analysis methodology used, demonstrates its validity, and provides an 

example demonstrating its application. It should be noted that the scope of this report is 

limited to the presentation of the investigative and analytical methodology, and does not 

include any detailed analyses of data obtained from the Board's accident investigations. 

CRASHWORTHINBSS PROGRAM 

The Safety Board's General Aviation Crashworthiness Program is a multiyear project 

initiated in October 1981. The field phase of the program was begun on January 1, 1982, 

concurrent with the introduction of an expanded Safety Board accident/incident report 

form (NTSB Form 6120.4). (See appendix B.) The program provides for a systematic 

investigation of general aviation airplane accidents with emphasis on crashworthiness. 

Crashworthiness investigations gather data that are useful in determining the 

adequacy of current airplane design practices which affect occupant survivability. The 

parameters determined from these investigations include the nature of the impact 

conditions of the airplane, the amount of structural deformation, the approximate forces 

imposed on the structure and occupants, occupant injuries; and injury-producing 

mechanisms-- both mechanical and accelerative. 

Program Obieetive and Goals 

The objective of the crashworthiness program is to develop and disseminate to the 

FAA and the general aviation industry an envelope of likely peak decelerative forces 

occurring in survivable'§_/ general aviation airplane accidents, and their effects on the 

occupants and airplane structure for the purpose of upgrading occupant protection design . standards. The program will describe and categorize, by severity, crash scenarios for a 

range of survivable airplane accidents. Also, the program will attempt to correlate the 

scenario categories with the savings in lives and the reduction in serious injuries which 

might be achieved by upgrading the design standards of general aviation airplanes to 

levels compatible with these scenario categories. 

The following goals have been set to accomplish the program objective: 

o Establish investigative techniques which will facilitate the 

collection and analysis of crashworthiness data for general aviation 

accidents. 

o Collect and evaluate, through detailed analysis, crashworthiness 

data on a select sample of survivable general aviation accidents. 

o Validate analysis techniques which can be applied to the future 

analysis of the substantial amount of crashworthiness data which 

will be collected routinely in general aviation accident 

investigations. 

'§_/ A survivable accident is one in which the forces transmitted to the occupant through 

the seat and restraint system do not exceed the limits of human tolerance to abrupt 

accelerations and in which the structure in the occupant's immediate environment remains · 

substantially intact to the extent that a livable volume is provided throughout the crash 

sequence. 
0 

0 

-4-

Define crash pulSes that describe the impact severity of survivable 

accidents in general aviation airplanes currently in use. 

Identify injury-producing mechanisms related not only to the 

fuselage structure, but to control/display designs, crew /passenger 

seats, and possible deficiencies in the availability and use of seat 

belts/shoulder harnesses, and correlate these with the crash loads. 

o Describe and categorize crash scenario severity based on changes 

in velocity and impact angle. 

o Use the crashworthiness data to validate past findings and to 

support future recommendations. 

· Data Requirements 

The crashworthiness evaluation of general aviation airplane accidents requires the 

collection of data addressing three areas: occupant injuries, impact severity, and the 

airplane's occupant protection capabilities. The causes of injury can be related to both 

the severity of the impact and the ability of the structure (including seats and restraints) 

to protect the occupant from the impact. These three areas are focused on by engineers 

in all vehicle crashworthiness design efforts. 

Occupant Injuries.-The occupant injuries of concern in the crashworthiness study · 

are those. resulting from either accelerative or mechanical sources. Abrupt 

acceleration.§/ (+ or-) of the body or parts of the body may result in injuries, such as 

hyperextension of the cervical spine (whiplash) from longitudinal acceleration, or 

transection of the aorta from acceleration in the vertical direction. Mechanical injuries, 

also referred to as blunt trauma or impact injuries, result from the body's striking or being 

struck by another object. A typical mechanical injury is a fractured skull or facial 

laceration which results from head contact with the instrument panel, seat back, or 

window jamb during a crash sequence. The detailed data concerning occupant injuries are 

collected from autopsy records, hospital records, and interviews with victims and 

medical/rescue personnel who responded to the accident. 

Identification of the injury mechanisms or the direct causes of the injuries, an 

important part of the investigation process, will provide information on the occupant 

protection capabilities of the airplane. Although injuries caused by accelerative forces 

may be identified as such, the magnitude of the forces causing the injuries must be 

identified through kinematic ']../ analysis of the airplane crash. Impact injuries, in general, 

can be traced by physical evidence to occupant contact with particular structures in the 

cockpit or cabin of the airplane. 

Airplane Impact Severity.-The severity of a crash is stated in terms of a crash 

pulse which relates acceleration ("G11) ~/ acting at the airplane's center of mass to time. 

The pulse is determi~ed by the analysis of the airplane's kinematics which is established 

§./Acceleration is the change in velocity wit.h respect to time. In general, the term 

"acceleration" refers to an increase in velocity with respect to time, and is expressed as a 

positive (+) number .. A decrease in velocity with respect to time is a negative ( -) 

acceleration, or a deceleration. · 

']_/ Kinematics is a branch of dynamics that deals with aspects of motion apart from 

consideration of mass and force. 

8/ Acceleration vs. time where acceleration in G's is the ratio of a particular 

acceleration to the acceleration of gravity. (See Glossary of Terms.) 

.f 

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I 

l 
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through the reconstruction of the crash sequence. The kinematic analysis requires 

knowledge of the velocity change of the airplane, the distance over which the velocity 

change took place during the principal impact,~/ the airspeed, the flightpath angle, the 

terrain angle, the airplane's attitude at the principal impact, and the sliding distance after 

the impact. These values are determined from physical evidence, including damage to the 

airplane structure, damage to objects in the crash path, and ground scars. Additional data 

that are useful in establishing the required parameters can be obtained from radar data, 

aerodynamic analyses, and flight data recorders when they are available. 

Occupant Protection Capabilities.-The determination of how well an airplane can 

protect its occupants in a crash depends on more than documentation of injuries and 

analysis of the airplane's kinematics. Information is required on how much energy of the 

crash was absorbed by the structure and components through plastic or permanent 

deformation. Also, information is needed on whether or not the occupants were 

restrained sufficiently to allow them to have participated in the airplane structure's 

deceleration, or whether or not they experienced an abrupt, and perhaps nonsurvivable 

deceleration, because the tiedown chain 10/ failed to restrain them. Such information is 

gathered during a detailed examination of the airplane wreckage. Also, fuselage 

deformation must be measured to determine whether a livable volume is maintained in the 

occupied area. Impact damage must be documented, and matched to the evironmental 

evidence, i.e., ground scars, tree strikes, and other collisions with obstacles, and evidence 

must be collected on seats and on the availability and use of restraints, and failures or 

deformation of these components and the components comprising the rest of the tie-down 

chain. 

ANALYSIS METHOD 

Impact Severity 

Impact severity can be determined through either an energy management analysis or 

a kinematic analysis. The energy management analysis uses detailed mathematical 

modeling o~ the main airplane structure, using finite element or lumped mass modeling 

techniques and requires indepth knowledge of the physical properties of major structural 

members and their responses under dynamic conditions. Similar techniques have' been 

employed to model the human occupant. Sophisticated computer programs, such as 

KRASH and SOM-LA (Seat/Occupant Model-Light Aircraft), which were developed as 

design aids and research tools, provide detailed analytical results of the dynamic response 

of the airplane and the occupant. However, because of the considerable time and 

technical expertise that are required to model different airplanes in order to utilize such 

programs, their use is precluded in day-to-day field investigations. 

The kinematic analysis adopted by the Safety Board simply requires data that can be 

collected at the crash scene using standard investigative techniques. The analytical 

process is straightforward and relatively simple to accomplish. The beginning and end of 

the principal impact are defined, and the peak decelerative force is derived from the 

estimated velocity change and the distance traveled by the airplane's center of mass 

~/ Principal impact occurs when the major decelerative forces are experienced ·and the 

most damage is sustained by the fuselage. The principal impact may not necessarily be 

the initial impact. 

10/ The seat, restraints, seat tracks, bulkhead/floor, subfloor structure, and attachment 

hardware which act as a system to restrain and to protect the occupant. 
-6-

·. during the impact. Because precise engineering information about the reaction of the 

structure between the starting and. the stopping points of the principal impact of a 

particular crash is not used, the kinematic analysis will not yield a unique crash pulse 

shape which describes the precise decelerative forces acting on the airplane throughout 

the crash. However, the analysis will provide a set of peak decelerative force values 

which should bracket the ·unique or actual peak force for that crash by determining the 

minimum possible peak decelerative force and the peak decelerative force for a triangular 

shaped ·pulse. In bracketing the actual peak decelerative force, the assumption is made 

that the decelerative forces are proportional to the mass of structure crushed, which in 

turn, influences the shape and magnitude of the crash pulse. This analysis methodology 

worked well when the NTSB applied it to crash tests of general aviation airplanes that 

were performed by NASA. 

To establish an envelope of representative crash forces from the bracketed 

solutions, it is necessary to use all known facts from field and test data to narrow the 

bracket for each crash pulse to approach its precise solution. However, as will be 

discussed further in the Method Verification section, the data available from the crash 

scene may be so limited that the kinematic reconstruction can be performed only for one 

direction, i.e., the physical evidence may be sufficient to allow an analysis of the vertical 

crash loads but may be insufficient to allow an analysis of horizontal crash loads. Also, 

evefl if in one accident all data could be measured precisely and loads calculated exactly, 

that accident would not necessarily be representative of all survivable. general aviation 

accidents. Therefore, a substantial number of crash analyses is required to establish the 

pulse(s) that are representative of current general aviation airplanes. While it is 

recognized that there are limits to the accuracy of these individual crash analyses, the 

overall program is expected to yield an envelope of peak crash pulse values of sufficient 

accuracy· and consistency to be usable in the formulation of requirements for 

crash worthiness airplane design and testing. 

Certain data needed to establish the crash pulses by kinematic analysis are obtained 

from two procedures. The first procedure is the visualization of the crash sequence, the 

results of which provide impact attitude and crushing distance. The second procedure is 

the development of a crash pulse that, when integrated, will generate the documented 

velocity change and stopping distance. 

Visualization 

Orthographic Drawing.-The most effective method of visualizing the impact 

attitude, flightpath angle, and the amount of crush that occurs is to create an 

orthographic drawing incorporating the impact data gathered in the field. Damage to the 

airframe, ground scars, and tree strikes can be . documented through the use of 

measurements, photographs, sketches, and drawings and notes made on airplane 

three-view drawings. When all available impact information is documented, 

reconstruction of the airplane's impact attitude is possible, and more confidence can be 

placed in the attitude reconstruction when several ground scars are present. The 

technique requires that the ground scars be aligned with the airplane components which 

caused them. Typically, distinctive gouge marks are left by components, such as landing 

gears, propellers, engine nacelles, and wing tips. Changes in the airplane's attitude may 

result from these components striking the ground during the crash sequence. 

Crush Line.-Another technique for establishing the impact attitude of the airplane 

is through the use of the crush line. The crush line is formed as a result of the airframe 

being crushed against a surface and leaving a distinctive flat or "stamped" area on the 
..... 

.,.. 

;"\II 

-7-

airframe. In g·eneral, the crush line can be identified by small, tight wrinkles in the skin, 

or by deformation of the airframe surfaces around longerons or stringers. This type of 

damage is caused by direct contact between the airplane and the ground. Points 

representing the edges of the damaged areas are plotted on an airplane three-view 

drawing and straight lines are drawn between these points. (See figure 1.) Several lines 

intersect to create an imaginary plane or fiat surface, i.e., crush line. The impact 

attitude can be determined graphically by relating the crush line to the impact surface • . The rotation required to place the crush line on the impact surface· defines the airplane's 

pitch, roll, and yaw attitudes at impact relative to that surface. Correcting for surface 

slope will yield these attitudes relative to the horizon. 

Once the crush line and impact attitude are established, a drawing is made with the 

airplane in that attitude. Lines can be added to the drawing parallel to the impact 

surface which will act as .distance marks and will help to display the progressive crushing 

of the structure up to the crush line or stopping point. (See figure 2.) 

The pitch attitude of the airplane at impact also can be calculated by a1gebraically 

adding the values for the fiightpath angle and the angle of attack. The fiightpath angle is 

determined by aligning sequentially tree or object strikes and the ground impact point. 

The angle of attack can be estimated based on the airplane's speed and maneuvers just 

before impact. Although not as precise as using several ground scars, the value for pitch 

attitude derived by this method is sufficiently accurate for purposes of analysis when no 

other information is available. (See Glossary of Terms.) 

Change in Velocity.-Once the stopping distance has been established, the change in 

velocity 11/ ·during the principal impact must be determined. The initial velocity is. 

estimated based on knowledge of the airplane's maneuvers just before impact, the 

airplane's performance parameters, the pilot's statement, or a witness statement. For 

example, an airplane may have been seen flying level in a nose high attitude and pitching 

over just before hitting the ground. From this information, it can be assumed that the 

airplane was at or near stall speed when the impact occprred. Another example is a 

twin-engine airplane that crashes out of control after power is lost in one engine. In this 

case, it iS reasonable to estimate that the initial velocity was near the airplane's singleengine minimum control speed (V ). Witness statements, radar data, and airspeed 

readouts from flight data recorderN;1f available, also are helpful in estimating the initial 

velocity. 

The total velocity component of the principal impact acts along the fiightpath. The 

flightpath angle is used to break down the total velocity component into its vertical and 

horizontal components, relative to the horizon. (See figure 3.) In the vertical direction, 

the final velocity is used to determine the velocity change. The final velocity usually is 

zero because the maximum vertical crush is achieved when the downward movement is 

stopped by the ground during the principal impact. As vertical velocity becomes zero the 

maximum vertical crush is achieved. In the horizontal direction, most airplanes tend to 

slide along the ground for some distance after the principal impact, and the difference 

between the initial velocity and the final velocity (a value greater than zero) must be 

established for the principal iii_lpact. 

11/ The change in velocity is the difference between the initial velocity (the velocity just 

prior to the principal impact) and the final velocity (the velocity just after principal 

impact). 
:1 

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Vv 

-

"'-....::::.. 

_ :> i _.HORIZON_T_A_L,_;___ 

PITCH ANGLE 

...... 

',, LONGITUDINAL AXIS 

~ 

Vfp~ ' ...... ..[ ...... 

""' 

FLIGHT PATH ANGLE 

' 

...... ...... 

' '-, 

STOPPING DISTANCE 

( HORIZONTAL (Sh) 

) VERTICAL ISvl 

HORIZONTAL 

IMPACT 

· 

ANGLE 

~~ -~~ TERRAIN ANGLE 

Gv 

Gr 

Figure 3.--Vector components. 

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-·- ~~-~--- ·- • 

I 

...... 

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-11-

In crashworthiness analysist the velocity change is the most critical item and is the 

most difficult parameter to estimate. In the formulas for the calculation of the G-loads, 

the velocity appears as a squared factor, thus magnifying small errors in the estimate. 

·Last second maneuvers of the airplane (controlled or uncontrolled) also can change the 

velocity by a small but important amount. Accounting for these changes is a difficult 

task and care must be taken to utilize all available information. 

After establishing values for distance and velocity changes during the principal 

impact, the final step is to estimate the horizontal and vertical crash pulsest or a 

combined pulse, which represents the change in velocity over the measured stopping 

distance. 

Pulse Shape Development 

Quick Look Analysis.--Because NASA general aviation crash test data shows that a 

triangular crash pulse shape accurately describes the principal impact in the test crashes, 

a triangular pulse shape (T) will be used to calculate the most reasonable peak 

decelerative force in the Safety Board crash analyses. The following formula will be used 

for calculating the triangular crash pulse shape: 

GT = V2

/gS 

where V = impact velocity (ft/sec) 

g = earth gravitational constant (32.2 ft/sec2) 

S = stopping distance (ft) 

The minimum peak decelerative force, based on the same change in velocity and distance, 

is calculated using the formula for the constant (rectangular shaped) pulse (C). The 

constant crash pulse shape is calculated using the following equation: 

G = V2/2gS 

where C V = impact velocity (ft/sec) · 2 

g = earth gravitational constant (32.2 ft/sec ) 

S = stopping distance (ft) 

The total time of the pulse is calculated as: 

t = V/gGC 

For example, figure 4 depicts an airplane that crashed in a 30° nose down attitude. 

The 4.6-foot line represents the total depth of crush. Impact velocity was 90 miles per 

hour, or 131.94 ft/sec. For the vertical crash pulse, the impact velocity would be V = 

131.94 Sin 30° 66 ft/sec. The minimum peak pulse in the vertical direction is ttYen 

calculated as: 

o c = v 2;2gs = 66 2 /2(3z.2> 4.6 =t.4. 1 °vc 

The triangular (ma~Imumf peak GvT = V v /gS = 66 /32.2 (4.6) or 29.4 G's, which, for this 

shape, is twice the minimum peak value. This results in a rarige (bracket) of 14.7 to 

29.4 G's. Both pulses require a time of: 

t = V v/gGvc = 66/32.2 (14. 7) = 0.139 second 
-12-

This method results in a fast and reasonably accurate "quick look" evaluation of an 

accident and only requires that the values for velocity change and total stopping distance 

be known. However, a more detailed approach will yield a more accurate crash pulse and, 

with the use of shaping techniques, the range of accelerations between the calculated 

minimum and maximum peak G-loads can be better defined, as shown below. 

CRUSH 

LIN~E~~4~.6~~r-------~~~~~~--~~--- 3., ~----f--.IIOo~~,.,e;._---------- } : 

0 

Figure 4.--Crash visualization. 

Detailed Analysis Based on Shaping Technigues.-The following example illustrates 

how a detailed vertical pulse shape is developed. First, as in the "quick look" method, a 

visualization of the crash is developed, including the parallel lines showing the increasing 

amount of structure involved as the airplane crushes. Figure 4 shows that the nose area, 

which is comprised of lightweight materia~ is involved in the first 1 foot of crush (a). At 

the 1-foot mark, the components involved· include some lightweight skin, the nose gear 

structure, and small frame structure (b). Starting at the 3.6-foot line, the structure being 

crushed includes the cockpit bulkhead, engine, engine mounts, cockpit floor, and side walls 

(c). 

As the crush progresses to the areas of. increasingly massive structure, higher 

decelerations, or G-loads, are expected to occur. Allowances are made in the analysis for . the differences .in the type and mass of the crushed structure. The least massive 

structure, referred to as nonproductive structure, is unable to support major loads and, 

thus, collapses easily. This structure has a crushing distance, but it does not produce a 

significant deceleration. In this example, the distance from 0 to 1 foot is comprised of 

lightweight material and imparts no crash loads to the occupants while it is crushing; 

hence, it is nonproductive. · 

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Nonproductive crushing is not considered when estimating acceleration levels in a 

pulse. However, an increase in the mass of structure involved will cause the crash pulse 

to be modified (shaped), based on the assumption that the magnitude of the crash pulse 

generally is proportional to the mass of structure being crushed. Correcting for 

nonproductive crushing and the increase in the mass of the structure involved is not 

precise, but these corrections make the results more accurate by eliminating large errors 

and by skewing the curves in a logical manner. 

Also, as in the "quick look" procedure, the minimum and triangular peak G's are 

calculated for the purpose of establishing a reasonable range of values. Since the first 

foot of crushing involves nonproductive structure, the stopping distance of 4.6 - 1.0 or 

3.6 feet is used in calculations. The minimum peak G then, is v2 /2gS = 66 2/2 (32.2) 3.6, 

or 18.79 G's, and the triangular peak load is v2 /gS = 66 2/32.2 (3.6), or 37.58 G's. These 

values become the minimum (19 G's) and maximum (38 G's) limits for the force values in 

the crash analysis. (See figure 5.) It should be noted that this step is quite easy and can 

be included in many quick look analysis. 

The next step in the detailed analysis is the modification or shaping of the constant 

(rectangular) pulse. This modification is performed to create a pulse magnitude and shape 

between the calculated minimum and triangular peak G-loads, which is more 

·representative of the actual impact. (See figure 5). The shaping technique requires that 

the area under the modified constant deceleration versus time cu.rve remains equal to the 

area under the unmodified curves, so that the velocity change remains the same. 

Target values for changes in distance (crush) and velocity, determined from the 

visualization and the physical evidence, are used to facilitate shaping of the crash pulse. 

Although the distance targets are fixed in magnitude, they can be moved along the 

abscissa, or time axis. Velocity targets also are fixed in·magnitude at the end points. The 

distance targets, which will be labeled (a) through (e) for this example, are set at ~' 1, 2, 

3, and 4.6 feet, respectively. (See figure 6.) The velocity. targets, labeled (f) and (g), are 

set at 66 ft/sec (~feet crush and~ time) and~ ft/sec (maximum crush and total time). 

Once the deceleration versus time curve has been established, it is integrated, 

generating the curve for velocity change. This curve, in turn, is integrated to generate 

the curve for distance change. (See figure 7 .) A computer program has been written to 

perform the iterative process necessary for the integrations. (See appendix C.) The 

results are presented as graphs. 

A four-tiered pulse is assumed, based on the previously set distance targets. Each 

tier of the pulse represents the average G-load over a given distance. For this case, an 

initial estimated value of 27 G's was assumed as the highest value for the modified 

constant pulse. Any of the values between the established maximum and minimum values 

may be chosen for the estimate. However, analytical experience has shown that the 

midpoint, 27G's in this case, is a reasonable value for the initial estimate. This value can 

be revised and the analytical procedure can be repeated for the number of iterations 

needed to satisfy the distance and velocity target criteria. 

The 27 G value and the distance targets are used to establish values for the relative 

magnitudes of the deceleration tiers. Judgment again is used in estimating how much of 

the total deceleration has occurred during each interval of crush. The results of these 

estimates are presented in tablet 
G's 

(-) 

-14-

------MAXIMUM 

G triangular 

(modified constant) 

~----l'-----------+----t--,-MINIMUM 

Gconstant 

TIME 

Figure 5.-- Minimum and maximum force limits. 
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Figure G.--Tiered crash pulse with targets. 

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-17-

Table I.-- Estimating target magnitudes for deceleration tiers. 

Crush Level (feet) Percent of Total Deceleration G's 

0-1 0% of 27 G's = 0 (G1) 

1-2 33 %of 27 G's = 9 (G2) 

2-3 66 %· of 27 G's = 18 (G3) 

3-4.6 100 % of 27 G's = 27 (G4) 

Although many methods can be used to establish target times, it is advantageous to 

make the estimates as accurate as possible. This reduces the number of iterations 

necessary to meet the fixed target values when shaping the pulse. A method for 

calculating the target time is presented below. 

After an average velocity is calculated for each segment, the average time for each 

segment is calculated, and the distance targets are set at these times. For segment 1 (0 - 1 ft), it is assumed that there is no change in velocity; therefore, the average velocity is 

66 ft/sec. The average time for this segment is calculated as: 

tave1 = S/V ave1 = 1/66 or 0.015 second. 

Since there was no appreciable change in velocity in the first segment, the starting 

velocity for the second segment (1-2 ft) also is 66 ft/sec •. For s2 = 1 ft, t

2 = 1/66 or 0.015 

ft/sec. The change in velocity for this segment is: 

ll. V 2 = gGs2 t, where Gs2 = the average G estimate 

for the segment, from table 1. 

ll. V 2 = 32.2(9)(0.015) = 4.35 ft/sec, 

giving an ending velocity of 66 - 4.35 or 61.65 ft/sec for this segment. The average 

velocity for the second segment is V 2 = 66 -2.18 or 63:82 ft/sec. The average time for 

ave 

the segment is tave2 = 1/63.82, or 0.016 second, for a cumulative time of 0.031 seconp. 

Segment 3 (2-3 ft) is treated similarly, resulting in a velocity change of 9.27 ft/sec, 

an ending velocity of 52.38 ft/sec, and an average velocity of 57.01 ft/sec. The average 

time for the segment is 0.018 second, for a cumulative time of 0.049 second. 

The velocity change in segment 4 (3-4.6 ft.) is from 52.38 ft/sec to 0 ft/sec, the 

final velocity. The average velocity is 26.19 ft/sec. The average time for this segment is 

tave4 = 1.6/26.19, or 0.061 second, for a total pulse time of 0.110 second. 

The distance targets (a) through (e) and velocity targets (f) and (g), are set at the 

following times: 

Distance Target (ft) 

0 (a) 

1 (b) 

2 (c) 

3 (d) 

4.6 (e) 

Velocity Target (ft/sec) 

66 (f) 

(g) 

Time (sec) 

0 

0.015. 

0.031 

0.049 

0.110 

The estimated crash pulse magnitude and the velocity and distance targets are entered 

into the computer program, the integrations are performed, and the curves are printed 
-18-

as graphs. For this case, the distance and velocity plots matched their respective targets, 

which indicates that·the pulse estimates were reasonable. (See figure 6.) 

If the targets had not been met, they could have been moved along the time axis, 

which would have required a corresponding movement of the deceleration tiers so that 

they remained aligned with the distance targets. The magnitude of the crash pulse 

estimate {G level) also can be modified, keeping in mind the limits imposed by the 

assumptions of nonproductive crushing and the proportionality of decelerations to the 

mass of structure involved in the crushing. 

It is possible to generate a number of crash pulse shapes that would be compatible 

with the estimated velocity change and stopping ·distance. However, factors which 

influenced the choice of the triangular deceleration pulse shape included: 

o NASA crash research tests which indicated that a representative 

tri8.ngular pulse exists for crashes of general aviation airplanes. 

o Deceleration increases as more structure becomes involved in the crush. 

Figure 8 shows the tiered pulse of figure 6 with a triangular peak. As stated 

previously, the tiered pulse in figure 6 represents the minimum limit of the range of peak 

forces for the crash. The peak value for the triangular pulse in figure 8 represents the 

new maximum limit for the pea):<: crash forces. As shown in the figure, all of the target 

values have been met, and the total pulse time has increased slightly so that the area 

under this curve remains equal to the area under the tiered curve. 

The corrections for areas of nonproductive crushing and the differences in the 

amount of structure involved in crushing developed during the analysis, have resulted in a 

narrowing of the range of likely forces from 19 G's (18. 79 to 37.58 G's) to 9 G's (27 to 

36G's). 

METHOD VERIFICATION 

Verification of the accuracy of the techniques used to determine the crash pulse was 

accomplished through the analysis of four NASA crash tests, using NASA's published 

data. 12/ This effort included comparison of Safety Board analyses based on physical 

evidence from NASA crash tests of general aviation airplanes with the actual parameters 

and results from those tests. Crash loads based on rectangular and triangular shaped 

crash pulses were calculated for each crash test. 

Pitch Attitude 

Several crash tested airframes, which were stored at the NASA Langley Research 

Center, were inspected and documented by Safety Board investigators, using the Board's 

normal accident investigation procedures. The goal of the exercise was to establish the 

airplane's impact attitude based only on the crush line and other fuselage deformation. 

Once the damage was documented and an impact attitude was established, a comparison 

was made with the NASA data, i.e., actual decelerations measured by instrumentation 

during the crash tests. 

12/ Vaughan, V .L., Jr., and R.J. Hayduk, "Crash Tests of Four Identical High-Wing SingleEngine Airplanes," NASA Technical Paper 1699, August 1980; and, "Determination of 

Crash Test Pulses and Their Application to Aircraft Seat Analysis," Society of Automotive 

Engineers, Inc., Technical Paper 810611, Apri11981. . · 
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-20-

The measurements taken from the crush lines of the test airplanes were found to 

approximate closely the airplanes' attitudes at full development of the crushing. The 

comparison measurements were taken from NASA's crash test films. The film analyses 

showed that when crashed on concrete, the airplanes tended to rotate or bend during the 

principal impact, causing a change in pitch attitude between 3° and 9°. An example of this 

pitcl) rotation was identified in the film of a 45° nose down drop test. The airplane 

initially contacted the ground at 45°, but at the fully crushed position, the fuselage had 

rotated to a pitch angle of 36°. In the analyses of other drop test films, it was found that 

several of the 30° nose down tests resulted in pitch attitudes of 26 °, and for 15 ° nose down 

tests, the pitch attitudes at full crush development were 12°. 

The crush line on test vehicle No. 14 is identified as the flat portion on the nose. 

(See figUre 9.) When measured, the crush line shows a pitch attitude of 10° nose down. 

(See figure 10.) The actual test resulted in a 12° nose down pitch angle at full 

development. 

Test vehicle No. 18 (see figure 11) illustrates how the use of only the crush line to 

establish attitude at impact can be misleading. The crush line is measured at 22°, but at 

full development during the crash, pitch was near 27°. The error in measurement is 

attributed to buckling of the fuselage· top which caused the crush line on the fuselage 

.bottom to stop development. Figure 12 shows the buckled area with a split rivet line. 

The rivet line is split 4 °, so the pitch at full development could be measured as 22° plus 4 °, 

or 26°. . 

Other techniques for estimating pitch attitude also were verified. One technique 

was the use of. distinct bend lines found in the floor boards of the test vehicles. The a 

floorboards of test vehicles Nos. 7 and 8 (see figures 13 and 14) retained their set after .~ 

the crash. In vehicle No. 7, the floorboards were set at 40° after a 45° nose down drop 

test, and the floorboards in vehicle No. 8 were set at 28° after a 31° impact. Parallel 

wrinkles in the fuselage skin were reasonable indicators of pitch attitude at full 

development of the crush. In general, the parallel wrinkles were found to be' valid 

indicators if they did not emanate from an area of major structure. Test vehicle No. 17 

has three parallel wrinkles on each side which end in an open area forward of the spar. 

(See figures 15 and 16.) These types of wrinkles were found to be usable with reasonable 

confidence to estimate pitch attitude. 

Figure 9.-NASA test vehicle No. 14. (Note flat area 

under nose in foreground.) 
-21-

• 

Figure 10.-Crush line on NASA test vehicle No. 14 • 

Figure 11.-NASA test vehicle No. 18. 
-22-

Figure 12.-NASA test vehicle No. 18 showing buckle and split rivet line. 

Figure 13.-NASA test vehicle No. 7. 

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-23-

Figure 14.-NASA test vehicle No. 8. 

Figure 15.-Parallel wrinkles on right side of nose on vehicle No. 17. 
-24-

Figure 16.-Parallel wrinkles on left side of nose on vehicle No. 17. 

Each of the techniques described is a useful tool for estimating pitch attitude at 

impact. However, an investigator must exercise sound judgment in basing conclusions on 

this evidence because each piece, taken by itself, can be misleading. Conclusions with the 

highest level of, confidence result from the use of a number of techniques to confirm an 

impact attitude. 

Crash Pulse.-A visualization of each test was made to establish the target values for 

distance. The NASA values for velocity and flightpath angle were used in calculating the 

crash pulse. The impact data could not be generated for the NASA tests as they would be 

in an NTSB field investigation. Velocity, impact attitude, angle of attack, and flightpath 

were artificially set for test purposes for the NASA tests and their values could not be 

estimated by using techniques that would be applied in the field. 

Crash pulses first were calculated relative to earth axes, 13/ then· converted to 

airplane axes 14/ to allow comparison with accelerometer data from the NASA tests. 

Initial evaluations indicated that when the airplane crashed on an unyielding surface, such 

as concrete, the predominant loading (reaction) occurred in the vertical direction relative 

·to the earth. Howeve.r, when the crash occurred on a yielding surface, such as dirt, the 

loads were predominantly longitudinal, relative to the airplane axis as it dug into the 

ground. 

13/ An axis system where the vertical and horizontal axes are normal and parallel 

respectively to the earth surface. 

14/ An axis system where the vertical and horizontal axes are normal and parallel 

respectively to the airplane's fuselage. ~i, j: 
• 

• 

-25-

ACTION 

) 

t REACTION 

~REACTION 

(a) Unyielding.Surface (b) Yielding Surface 

Figure 17 .-Direction of reactions. 

Stated in another manner, in both cases, the reaction to the force of the impact was 

normal, or at right angles to the impact surface. This reaction follows Newton's third law 

of motion which states that, for every action, there is an equal and opposite reaction. In 

figure 17, the principal impact surface in (b) is redefined as the airplane ploughs into the 

ground, resulting in a predominant loading along the airplane's longitudinal axis, while in 

(a), the predominant loading occurs in the direction normal to the unyielding surface. 

If the airplane crashes on a yielding surface but does not dig in and stop, the 

physical evidence must be carefully evaluated to determine in which axis the predominant 

loading occurs. Identification of the predominant axis is important because analysis of 

the crash loads along this axis is more accurate and more easily accomplished rather than 

attempting the analysis in a nonpredominant axis, and. then translating the results to the 

predominant axis. 

Some disagreement will arise in the comparison of the published test data with the 

calculated crash pulse data during verification because the time histories of the vertical 

and· horizontal pulses cannot be compared. If the vertical and horizontal crash pulse peaks 

do not occur at the same time, the vector analysis, using the vector sums, is not entirely 

accurate. However, the calculations for the predominant pulse and the total vector sum 

· will be reasonably accurate. 

Analysis Summaries 

The following summaries of the comparative analyses of two NASA crash tests 

illustrate the application of techniques developed for use in the field. 

NASA Test No. 8 (Unyielding surface) 

Test Data 

Flightpath angl~ 

Pitch angle 

Velocity 

Vertical velocity change · Horizontal velocity change 

-30°(down) 

-25 ° (nose down) at full development 

88.6 ft/sec 

44.3 ft/sec 

20ft/sec 
-26-

The test data were taken from NASA publications and crash test films. The 

flightpath and pitch angles were 30° down at initial contact. By the time the fuselage 

crush had reached full development, the pitch angle had decreased to 25 o nose down, 

which was in agreement with the measurement of the crush line. The velocity at impact 

was measured at 88.6 ft/sec. The initial vertical velocity was 44.3 ft/sec {V = 88.6 Sin 

30° = 44.3 ft/sec) for a vertical velocity change of 44.3 -0 or 44.3 ft/sec. Thl horizontal 

velocity change given in the data was 20 ft/sec, which resulted in an ending velocity of 

56.7 ft/sec (V h = 88.6 Cos 30 ° = 7 6. 7 ft/sec, and 76.7 -20 = 56.7 ft/sec). 

Visualization.--The visualization in figure 18 was derived from field notes and still 

photographs of the wreckage taken by Safety Board investigators. The initial velocity 

vectors and flightpath angle are presented on the visualization. · Progressive crushing is 

shown by parallel lines at 1-foot increments, which represent the depth of the crush up to 

the maximum crush or full development at 3.6 feet. The crush line, which started just 

under the leading edge of the wing, the floorboards, and the wrinkles in the fuselage skin 

show that at the 3.6-foot crush mark, the pitch angle was 25° nose down; this was 

confirmed by the film data. 

The structure involved in the various levels of crushing is shown in table n. The 

crush from 0 · to 1 foot involves nonproductive structure. At 1 foot, the nose gear 

structure becomes involved, and deceleration begins to increase in proportion to the mass 

of the nose gear structure. As the crush progresses toward the cockpit floor, more 

substantial structure becomes involved and higher loads are transmitted to the cockpit 

area. 

Table H.-Structure involved in various 

levels of crushing in NASA Test No. 8. 

Crushing Distance (ft) 

0-1 

1 -: 2 

2-3 

3 - 3.6 

Vertical Deceleration ( Gv' earth axis) 

Assume net crush 

Velocity ~ange 

· Gvc = v /2gS 

= 44.32/2 (32.2) 2.6 

= 11.72 G's 

GvT = 2 (11. 72) 

= 23.44 G's 

= Y/g Gvc 

= 44.3/(32.2) 11.72 

= 0.117 sec 

Structure Involved 

Nose structure (nonproductive) 

Nose gear 

Engines; c9~kpit 

Engines, cockpit (full development) 

3.6 -1.0 = 2.6 ft 

44.3 ft/sec 
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-28-

Since the impact was on a flat, unyielding surface, the predominant loading was in 

the vertical direction in earth axis. Since the first foot of crush (8-1 ft) involved 

nonproductive structure, the net crush was 2.6 feet. The constant deceleration pulse peak 

value. (G c> was 11.72 G's; this value was doubled to obtain the triangular shaped pu~e 

peak vai8e of 23.44 G's. The pulse duration was 8.117 second. 

Horizontal Deceleration (Gh' earth axis) 

Velocity change 20 ft/sec 

t = 8.117 sec (same as for vertical pulse) 

GhC = Vh /gt 

= 20/(32.2) 8.117 

= 5.31 G's 

GhT = 2(5.31) 

= 10.62 G's 

Airplane Axis--The first portion of the analysis yielded a vertical peak pulse of' 23.44 G's · 

with a horizontal peak pulse of 10.62 G's in earth axis. The vector sum of the two pulses 

was a single pulse of 25.73 G's. To compare this analysis to the NASA data, the total 

pulse' was broken down into two vectors relative to the airplane axis to coincide with the 

accelerometer alignment used in the tests. To obtain these values, the reference axis was 

rotated 25° from earth axiS to ail'plane axis. (See figure 19.) 

25.73 G's 

\ 16.75G's ~ 

\ AIRPLANE 

\ AXIS 23.44 • ~ G's \._.../" 

,..,. 

/ 

19.53 G's 

EARTH AXIS 

Figure 19.-Translation of forces into airplane axis. 

Angle A = Cos -\10.62/25. 73) 

Angle A= 65.62° 

Angle B = 65;62-25 = 40.62° 

Solving for the vector components in airplane axis: 

Gv = 25.73 Sin 40.62 = 16.75 G's 

Gh = 25.73 Cos 40.62 = 19.53 G's 

The total vector sum remained at 25.73 G's. 
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-29-

Shaping of the Vertical Pulse.--The shaping technique is completed as in the example for 

pulse shape development. Distance and velocity targets will be set at 0, 1, 2, 3, and 

3.6 feet, and 44.0 and 0 ft/sec, respectively. The highest value for the modified constant 

pulse is at 18 G's or halfway between the calculated constant and triangular peak G's (G c 

= 11.72 and Gt = 23.44). . 

Table lll.-Target magnitudes for deceleration tiers for NASA Test No. 8. 

Crush Level (feet) 

0 -1 

1 - 2 

2 - 3 

3 - 3.6 

Percent of Total Deceleration 

0% of 18 

33% of 18 

66% of 18 

100% of 18 

G's 

0 

6 

12 

18 

The calculated velocities and times for each segment are presented in Table IV with their 

corresponding distance targets. 

Table IV.-Shaped crash pulse generation for NASA Test No. 8. 

Distance Velocit~ Incremental Time Total Time 

0 44 0 

1 44 .0227 .0227 

2 39.6 .0239 .0446 

3 30.4 .0286 .0752 

3.6 0 .0752 .1146 

The results of the first iteration of the computer run are shown in figure 20. The 

velocity and distance targets were not met. The time. increments and tne reliltive 

magnitudes of the acceleration plateaus were adjusted in subsequent iterations until the 

fixed target values were met. Figure 21 shows the final iteration of the modified 

constant pulse. 

A shaped triangular pulse was generated using the data from the final iteration of 

the modified constant pulse. (See figure 22.) The total velocity and distance changes 

remained the same, while the peak vertical load increased to 24.5 G's and total time 

increased slightly. 

Insufficient detailed data exist for shaping the horizontal pulse. However, since a 

value for the horizontal pulse must be used in translating the deceleration levels from 

earth axis to airplane axis, the calculated ho.rizontal value of 10.62 G's was used. 

Converting to airplane axis, the total pulse is 26.7 G's, the horizontal pulse is 20 G's, and 

the vertical pulse is 17.7 G's. · 

The loads from the published test data compared closely with the calculated and 

shaped analytical results shown in table V. 
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o.t4 0.16 

Figure 21.-Final modified constant pulse, NASA Test No. 8. 
-32- ! 

.~ 

;: 

E 

C'f '.~'i. 

~ •. I ~!J 

0 ~~} 0 0 0 0 0 ., N 

... ... 

0 0 0 II) CD 0 N ,.., ..,. I 

0 0 0 0 0 N ..,. ., ,.., ,.., N -- I 

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0 ., 0 

0 0 0 ... 0 0 

0 . 0 ... 

0 0 0 0 ., 0 ' o.o2 0.04 o.o& o.os 0.10 0.12 0.16 

TIME 

j 

.\ 

Figure 22.-Final triangular pulse, NASA Test No. 8. 
;f, 

,, '. 

Total 

Vertical 

Horizontal 

NASA Test No. FAA 4 

Test Data 

Flightpath angle 

Pitch angle 

Velocity 

-33-

Table V.--Actual NASA results versus NTSB 

analytic results in NASA Test No.8 

Actual 

24 

18 

16 

G-Loads 

Calculated 

Analytical 

26 

17 

20 

(Yielding surface) 

-32°(down) 

-34.5°(nose down) at impact 

Vertical velocity change 

Horizontal velocity change 

83 ft/sec 

42ft/sec 

49 ft/sec 

Shaped 

Analytical 

27 

18 

20 

Since the nose of the airplane ploughed into the soil at impact, it was assumed that 

the predominant loading was along the airplane's longitudinal axis. Test data showed an 

impact velocity of 83 ft/sec, and a flightpath angle of 32° down. Vertical velocity at 

impact was 43.98 ft/sec (V v = 83 Sin 32 = 43.98 ft/sec), for a vertical velocity change of 

43.98 -0 or 43.98 ft/sec. The horizontal velocity component at impact was 70.39 ft/sec 

(V h = 83 Cos 32 = 70.39 ft/sec). The horizontal exit velocity (start of slide) was measured 

at 20 ft/sec from the test film. This value also was calculated, using a sliding coefficient 

of friction of 0.5, and a sliding distance of 12 feeL The calculation [ v2 = 2(32.2) 0.5 (12)] 

resulted in a velocity of 19.66 ft/sec. An initial velocity of 70.39 ft/sec and an exit 

velocity of 20 ft/sec, resulted in a horizontal velocity change during the principal im'pact 

of 50.39 ft/sec. 

Visualization.--The visualization in figure 23 was derived from notes, photographs, and 

film data. This accident would have been difficult to reconstruct accurately in the field 

because the forward rotation of the airplane at impact caused crushing that gave the 

appearance of a 70° to 80° nose down pitch attitude. Reliance only on the crush line would 

have been inaccurate; reference to ground scars or tree strikes would have been necessary 

to establish a more accurate impact attitude. 

The crush line was identified as starting just aft of the wing struL As shown in 

table VI, the structure involved in the first 1.5 feet of crush involved the nose gear only 

and would have a negligible effect on the deceleration. The next 0.5 foot of crush 

involved some of the engine cowl structure and also was nonproductive. The crush from 

2.J) to 3.6 feet included the engine, firewall, and floor structure. Thus, the total effective 

crushing distance on the airplane was 1.6 feet, and with surface gouging estimated at 

6 inches or 0.5 foot, the total stopping distance was 2.1 feet. 
-34-

c! 

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Cd 

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< 

< 

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tl 

Q) 

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.r 

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. "· 

-35-

Table VI.-8tructure involved in various levels 

of crushing in NASA Test No. FAA 4. 

Crushing Distance (ft) 

~ - 1.5 

1.5 - 2.0 

2.0 - 3.6 

Structure Involved 

Nose gear (nonproductive) 

Engine cowl (nonproductive) 

Engine, firewall, floor structure 

Vertical Deceleration (Gv' earth axis) 

Assume net crush 2.1 ft 

Velocity change 43.98 ft/sec 

G = V2 /2gS vC 

= 43.982/2 (32.2) 2.1 

= 14.30 G's 

GvT = 2 (14.30) 

= 28.60 G's 

tv = V/g Gvc 

= 43.98/(32.2) 14.30 

= 0.~6 sec 

Horizontal Deceleration (Gh' earth axis) 

Airplane Axis 

Velocity change 50.39 ft/sec 

t = 0.096 sec (same as for vertical pulse) 

GhC = Vh /gt 

= 50.39/32.2 (0.096) 

= 16.30 G's 

GhT = 2(16.30) 

= 32.60 G's 

The force~ in earth axis are translated into airplane axis as follows: 

Angle A = 41.26° 

Angle B = 41.26 -34.5 = 6. 76 ° 
/ 

/ 

/ 

.;.36-

/ 

/ 

/ 

/ 

AIRPLANE 

AXIS \7 

, 

/ 

/ 43.07 G's 28.60 G's 

32.60 G's EARTH AXIS 

Figure 24.-Translation of forces into airplane axis. 

Solving for the vector components in airplane axis: 

G = 43.37 Sin 6.76 = 5.11 G's 

v 

Gh = 43.37 Cos 6. 76 = 43.07 G's 

The total vector sum remained at 43.37 G's. 

( 

The comparison of actual and analytical results shown in table Vll, indicates that 

in the predominant axis and for the total pulse, the analytical values again compared 

closely with actual test data. 

Total 

Vertical 

Horizontal 

Table Vll.-Actual NASA results versus NTSB 

analytical results in NASA test No. FAA 4. 

Actual 

40-45 

15 

40-45 

G-Loads 

Analytical 

43 

7 

43 

In the comparisons of the results of the actual and analytical loads from NASA tests 

No. 8 and No. FAA 4, in genera~ the analyses performed by the Safety Board appeared to 

have a high degree of accuracy and would indicate that the investigative methods and 

analytical assumptions used in the crashworthiness investigations were valid. 

•. \ . ·~~~ ,I 
1 ~ .•. · .. ,: ~ ' 

. ' 

-37-

In many cases, insufficient data exist to allow an accurate estimate of exit 

velocities, especially relative to the horizontal In these cases, an analysis can· be 

performed which will establish only a relative crash magnitude. The analysis is performed 

only in the predominant axis. · 

For NASA test No. FAA 4, the predominant axis is the longitudinal axis of the 

airplane. The measurement from the visualization shows that the longitudinal stopping 

distance is 3.6 feet, and with the 0.5 foot of gouging, the total longitudinal stopping 

distance is 4.1 feet. The velocity can be estimated as changing from 83 to 20 ft/sec at 

the start of the slide, for a velocity change of 63 ft/sec. The minimum peak loading can 

then be calculated as: 

= (V1

2 -V/)!2gS 

= (832 -202)/2(32.2) 4.1 

= 24.58 G's 

The peak of the triangular shaped· pulse would be 49.15 G's total longitudinal 

deceleration. This method does not allow a calculation for the vertical pulse to be 

performed in airplane axis. Additionally, the velocity change from 83 to 20 ft/sec is not 

precisely correct because the directions of the velocity vectors were not taken into 

account; the 83 ft/sec acts at 32, 0 but the 20 ft/sec acts parallel to the earth. However, 

the corrections for these errors would be small, and the results would be within 

acceptable limits for use in this type of analysis. 

APPLICATION OF ANALYSIS OF NTSB ACCIDENT INVESTIGATION DATA 

The following example is representative of a· typical application of analysis from an 

NTSB accident investigaion: · 

A Beechcraft 899 airplane was on an instrument landing system (ILS) approach to an 

airport in fog and light turbulence. The copilot stated that while on final approach, 

the ''bottom dropped out." The airplane crashed on an ice covered bay, and slid 

about 350 feet before coming to rest on the shore. (See figure 25.) 

Two crewmembers and five passengers were injured. The most extensive injuries, 

which were received· by the captain, included compression fractures of vertebrae, 

fractured lower legs, and head and internal injuries. The copilot received minor 

injuries. The passengers received flail-type injuries, including a fractured arm, 

fractured knee, head and facial injuries, and various contusions and lacerations. 

The investigation included interviews of passengers and. crew and an onsite 

documentation of the crash path, fuselage, ·seats, and restraints. Photographs taken 

at the accident site showed the crush line and general fuselage damage. (See 

figures 26 through 29.) The crush line was documented further on a three-view 

drawing of the airplane. {See figure 30.) 

The crush line in the photographs and the three-view drawing were consolidated into 

·a separate drawing in which the crush plane was rotated to the horizontal position. 

{See fjgure 31.) Parallel lines, labeled 1 through 5, were drawn to r¢present the 

crush levels at which different parts of. the structure became involv¢d during the . crash. The airplane attitude, measured directly from the drawing,tshowed a roll 

angle of 21° left wing down and a nose down pitch attitude of 9°. · 
-38-

., 

F~ure 25.--Airplane position and direction of slide. i 

; 

Figure 26.-Left side crush line. 
-39-

• ' i i 

' \ 

:.: 

Figure 27 .-Right side crush line. 

Figure 28.-Interior cabin damage. 
-40-

Figure 29.-Damaged seat. 

The airplane was assumed to be near stall speed, based on the copilot's statement 

that the ''bottom dropped out." Since the wind was near zero, it was assumed that 

the ground speed and airspeed were. the same, near stall speed. Stall speed for the 

airpiane with the power off and 30 percent flaps, was 86 KTAS (knots true airspeed). 

A stall angle of attack near 12° with an estimated pitch rotation of 2° and a pitch 

angle measured at 9° yielded a possible flightpath angle of 23°, based on the 

following equation: 

Flightpath angle 

Flightpath angle 

= 

= 

= 

Pitch angle+ angle of attack + pitch rotation 

go+ 120 + 2o 

23° 

Since there was no supporting data, such as ground scars or tree strikes, the 

estimate of angle of attack and pitch rotation were not used with the same degree 

of confidence as was the crush line measurement, which was the most accurate 

datum available for this analysis. 

The velocity was calculated by first converting the total velocity of 86 KTAS to 

feet per second. 

V = 86 (1.69) = 145 ft/sec 

Vertical velocity was then calculated as: 

= V Sin (flightpath) 

= 145 ft/sec Sin 23° 

=57 ft/sec 
-..J 

J: 

tl) 

:::J 

a: 

(J 

~ 

-41-

w 

z 

::::i 
CRASH 

INVOLVEMENT 

1. WING TIP - 0 FT 

2. ENGINE___, 2.28 FT 

3. FUSELAGE- 3.30 FT 

4. COCKPIT - 4.00 FT 

5. FULL STROKE- 6.12 FT 

-- \ ~--...,.,......',:.. 3 

Y\~ 2 

SCALE= 144 in/in 

PITCH= -9° 

FLIGHT P.ATH = -2° -9° -12° = -23° 

STALL SPEED- POWER OFF, 30% FLAPS= 

82 KCAS = 86 KIAS = 86 KTAS 

ROLL= 21 ° LEFT 

Vv = 145 FT /SEC sin 23° = 57 FT /SEC 

CRUSH LINE 

1 

Figure 31.-B99 visualization. 

~ , ... , .. ~... .,. »··, -·w-_..,.... 'M' I lll---1 'on _,.,..,.,-.. ..,~~._,. .. ;o•·' 

.. I~ ~~~-"'~'}') 

J.. 

~· 

I 
(0 

-43-

The first distance target was set at 3.3 feet, the distance from the wing tip to the 

beginnings of fuselage involvement. Using an entering velocity of 57 ft/sec, time 

for the first segment of the pulse was calculated as: 

tl = 81/V1 

= 3.3 ft/57 ft/sec 

t

1 = 0.058 sec 

This time corresponds to target A (3.3 feet, 0.058 second) in figure 32. The 

deceleration which began to increase more rapidly as the fuselage was crushed, is 

shown by a correspond.ing increase in the magnitude of the crash pulse. 

The second distance, target B, was set at 4~0 feet total distance where the cockpit 

became involved. The time for this segment was calculated as: 

t2 = S2/V2 

= (4.0 ft - 3.3 ft)/56 ft/sec 

t

2 = 0.013 sec, or about 0.071 second cumulative time. 

Target B was then plotted at 4.0 feet and .071 second. (The velocity component for 

each time calculation was estimated, based on the mass of structure involved.) · 

In the last segment, the velocity was estimated to have dropped to 52 ft/sec; the 

corresponding distance value was 2.12 feet, (6.12-4). This distance value is used in 

the calculation of a constant crash pulse because it represents the involvement in 

the crash of those portions of the structure having the most significant effects on 

the change in deceleration. The constant pulse was calculated as: 

ave = v

2

/2gS 

= 522/2(32.2) 2.12 

= 19.8 G's 

The time for this pulse was calculated as: 

t = V/gGvc 

= 52/32.2 (19.8) 

t = 0.082 sec. 

The duration of the total pulse was 0.153 second (0.071 + 0.082). 

The calculated data points were entered into the computer, and the program was 

run. Distance targets, which are fixed in magnitude, were adjusted. on the time 

scale until the final distance target of 6.12 feet and the final vertical velocity 

target of zero were met simultaneously. This resulted in the calculation of a 19.50 

constant vertical crash pulse for a total time of 0.157 second. . (See figure 32.) 
0 0 0 0 <V ,;, ...... 

0 0 0 N .... .... "' 

0 0 0 

• .D 

"' "' 

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0 0 0 (l) 0 

• • 

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w (f) > 

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0 0 <0 0 

(X) 

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I 

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t 

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u 

u 

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-44-

{ . 

--

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--

-- i 

~ 

~ DISTANCE I c)L ti: 

! .. -"1~ ~ f.!.-"' v Ill ..... ,._ I~ ,..... 

\ / I 

I 1/ \ I B.J S<1 ~ I 

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I !A?J I ! :\ I r \ !1!. 

/I l 

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I I 

I \ ACCELERATION ! -

/ I i\ 

J ~ I ,,\ 

I I/~ ' "'p 

---· ,l 

0-02 0-04 0.06 o.os 0.10 0-12 0.14 0-16 

T !ME 

Figure 32.-Crash pulse with targets. 

( ; 

I 

I, 
r (D , .: 

\\I .... -

l 

-45-

. . Figure 33 shows the results of substituting the plateau type pulse shape with the 

triangular pulse shape. Adjustments were made so that the distance and velocity 

targets still were met. The triangular pulse shape, which is more consistent with 

pulse shapes resulting from crash tests, showed a short duration peak load of 30 G's 

acting on the airplane near the point of impact. 

This example analysis shows the importance of the visualization technique not only 

for reconstruction of the impact attitude and the overall crash pulse development. 

It also explained the differences in the injury patterns of the occupants. In this 

case, the pilot received serious injuries, while the copilot who received minor 

injuries, was able to be present at the crash scene the day after the accident. 

Examination of the cockpit showed that the floor area under the pilot's seat was 

totally disrupted and that the front edge of the seat had broken in an upward 

direction. The copilot's seat showed evidence of downward loading. 

Figure 31 shows that the crush line on the left side of the airplane was high enough 

to be above the seat pan of the pilot's seat. However, because of the roll attitude of 

the airplane at impact, the crush line remained below the seat pan of the copilot's 

seat. The crushline is equivalent to ground level; therefore, the pilot and his seat 

physically tried to penetrate the ground --a rigid surface -- thus, bending the front 

of the seat up and transmitting loads greater than 30 G's to the pilot. On the other 

hand, the copilot's seat stayed above ground level, allowing it to act as a buffer or 

cushion between the copilot and the ground (crush line), and reducing the loads 

transmitted to him to below the 30 G peak. 

CONCLUDING REMARKS 

This report, which is a result of the first phase of the crashworthiness program, 

presents a methodology for the crashworthiness investigation and analysis of general 

aviation airplane accidents. Results of Safety Board documentation and analysis of two 

NASA general aviation crash tests using the methodology presented, compared well with 

NASA's published test data. This indicates that the methodology and assumptions 

developed for use in this program are valid. 

As of November 30, 1982, the Safety Board had conducted 31 full crashworthiness 

investigations. Of these investigations, 74 percent, or 23, of the airplanes involved in the 

accidents were Pipers or Cessnas, with Beech representing an additional16 percent or 5 

airplanes. Single engine airplanes represent 87 percent, or 27 airplanes. (See appendix D.) 

The current phase of the crashworthiness program, which includes the investigation 

and full analysis of a select sample of general aviation accidents, is not yet complete. 

However, preliminary findings tend to confirm the problems defined in past 

recommendations. Also, some preliminary findings indicate that problems. may exist 

concerning the adequacy of seat and restraint certification and testing, and the ability to 

maintain these items in a condition in which they will continue to meet at least the 

minimum standards under which they were certificated. 

The second phase of the program will include the presentation of the results of the 

analyses and correlation of the results. Recommendations ·addressing safety issues 

discovered as a result of the investigative process also will be included with the 

presentation of the second phase results. 
0 

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-46-

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~·~~~J~~~~~~ 

fJ VELOCITY \ I 

0 

0 

o.o2 o.o4 0-06 • o.os 0.10 

TIME 

0.12 

Figure 33.-B-99 shaped triangular crash pulse. 

0.14 o. 16 

f 
0 ' i i ' 

' 

l 

-47-

BY THE NATIONAL TRANSPORTATION SAFETY BOARD 

June 27, 1983 

/s/ JIM BURNETT 

Chairman 

Is/ PATRICIA A. GOLDMAN 

Vice Chairman 

/s/ FRANCIS H. McADAMS 

Member 

Is/ G. H. PATRICK BURSLEY 

Member 

/S/ DONALD D. ENGEN 

Member 
(1) Airspeed 

(2) Flightpath 

(3) Pitch Attitude 

( 4) Angle of Attack 

(5) Terrain Angle 

-48-

GLOSSARY OF TERMS USED IN THE 

CRASHWORTBINESS PROGRAM 15/ 

The airplane's velocity along the flightpath, 

expressed in knots. True airspeed (airspeed 

corrected to standard· atmospheric conditions) is 

preferred. However, since it is anticipated that the 

accuracy of the velpcity estimates will be coarse, 

indicated airspeed (airspeed .read directly from the 

airspeed indicator). can be used. Exceptions to this 

would include accidents occurring at high 

elevations, or accidents resulting from spins, where 

the indicated airspeed may be near zero, but 

vertical velocity :is high. The airspeed in knots is 

converted to feet per second for use in the 

kinematics equations. 

The path the airplane makes through the air. When 

measured relative to the horizon, the value for 

flightpath angle is derived. The flightpath angle is 

expressed as a negative number when the airplane is 

descending and as a positive number when the 

airplane is climbing. (See figure Al.) 

The direction in which the airplane is pointed., When 

measured from a longitudinal reference line on the 

airplane (usually the waterline, rivet line, or window 

sill line) to the horizon, the pitch angle of the 

airplane is derived. The pitch angle is expressed as 

a negative number when th~ airplane is pointed 

down and as a positive number when the airplane is 

pointed up. (See figure A2.) 

The difference between pitch angle and flightpath 

angle. For purposes of kinematic analyses, effects 

of nonhorizontal winds typically are not taken into 

account (See figure A3.) 

The difference between the slope of the terrain and 

the horizon. An upslope relative to the airplane's 

flightpath is expressed as a positive number, and a 

downslope relative to the flightpath is expressed as 

a negative number. (See figure A4.) 

15/ The glossary terms are not presented in alphabetical order. Instead, they are 

presented in order of development; one term combining with a subsequent term to define 

yet another term. 

i r·, 

•: i~ 
(~~···· 

~/ 

..,.. 

~ 

\?~I 

~ 

f\..\Gl'\1 p~1l'\ 

'---FLIGHT PATH ANGLE 

Figure Al.-Flightpath and flightpath angle. 

~ 

··':~'~:i":>)<i'i' -~~'!'~~~ 

HORIZON 

~ <0 

I 
..Jw 

<(~ 

Z..J 

aw 

:::;,U 

t-Z 

-w 

C!Ja:: 

zw 

ou.. ..Jw a: 

J: 

(.) 

1-

a: 

-

z 

0 

~ 

a: 

0 

J: 

-soz 

0 

N 

a: 

0 

J: 
--=-

~ 

~ 

LONGITUDINAL 

REFERENCE LINE 

ANGLE OF 

ATTACK(+) 

., ~ 

PITCH 

ANGLE(+) 

Figure A3.-Angle of attack. 

HORIZON 

=--

~~­

- "r~ 

.,...---.,.. 

J. 

.... 

I 
J: 

~ tJ: 

(!) 

::::i 

LL 

0 

tw 

> 

5 

w 

a: 

-52-
(6) Impact Angle 

(7) Impact Speed 

(8) Crush Line 

(9) Further Relationships 

of Definitions 

(10) Acceleration 

(11) G 

-53-

The algebraic sum of the flightpath angle and the 

terrain angle. (See figure AS.) Figure AS shows the 

relationship of the above definitions. 

The velocity of the airplane at the principal impact, 

expressed in ft/sec. Airspeed can be corrected for 

wind to obtain impact speed. 

The line denoting the extent of damage caused by · the airplane structure crushing against the ground. 

The crush line, which represents the ground plane, is 

used to show the depth of crush (stopping distance) 

and the airplane's attitude at impact. (See 

figure A7.) 

Pitch Angle-Flightpath Angle= Angle of Attack 

Flightpath Angle-Terrain Angle = Impact Angle 

Pitch Angle-Terrain Angle = Crush Line 

Crush Line-Impact Angle = Angle of Attack 

The rate of change of velocity. 

a= dV/dt where a = Acceleration 

V =Velocity 

t =Time · 

The ratio of an acceleration (a) to the acceleration 

due to gravity (g = 32.2 ft/sec2). 

G = a/g 
~ 

~J 

FLIGHT PATH ANGLE 

TERRAIN ANGLE 

Figure A5.-Impact angle. 

',1,, 

HORIZON 

~ 

~ ol:ao. 

I 
~ 

'~ 

..., 

~ 

,~-

u 

HORIZON 

f\.\G\-\1 p~1\-\ 

Figure A6.-Relationship of definitions. 

~-----------~~ 

~­ ··.:.- :./ 

.. 

HORIZON 

ch 

(.11 

I 
-56-
-57 

APPENDIX A 

NATIONAL TRANSPORTATION SAFETY BOARD 

GENERAL AVIATION CRASHWORTHINESS RECOMMENDATIONS 

AND FEDERAL AVIATION ADMINISTRATION RESPONSES 

Synopsis: On January 11, 1973, a Piper PA-28-180, N8964J, crashed landed in an orange 

grove after the engine failed in flight. Three occupants were seriously injured and one 

was fatally injured. As a result of its investigation of the accident, which disclosed 

failures in the rear passenger seatbelt cables, the Safety Board recommended on July 31, 

1973 that the FAA: . 

IsSue an Airworthiness Directive for all Piper PA-28-140/180 aircraft, 

which have the rear bench seat installation, to require replacement of 

the present 1/8-inch diameter seatbelt attachment cable with a stronger 

cable, or, alternatively, to reroute the present 1/8-inch cable to 

eliminate the stress concentration which may result from the cable 

contact with the seat frame. (A-73-56) 

On August 10, 1973, the FAA responded that the static. test of the seatbelt 

installation demonstrated a strength of 12g in the forward direction. The test conditions 

exceeded requirements, since the test loads included combined loading with forward, 

upward and sideward components, which resulted in more severe conditions than straight 

loadings in each design direction applied separately. An FAA review of the seatbelt 

installation showed that the attachment cable does not come into contact with the seat 

frame within the design envelope. The seat frame and structure would have to fail and 

deform before contact can be made. Since the rear seat frame in the area of the cable is 

a round tubing material, it would not result in an unusually high stress concentration on 

contact. The strength of the 1/8-inch diameter cable is 2,000 pounds in tension. This is 

higher than the minimum required seatbelt strength and the strength of the seat. Review 

of the PA-28 service records showed no previous case of this type of failure since type 

certification in 1960. The accident report indicated that high impact loads were 

transmitted to the structure as a result of hitting trees and the ground. The right wing 

was completely broken off, the left wing was almost severed, and major structural 

damage was inflicted. The FAA concluded that the installation met strength 

requirements but that loads in excess of design requirements were imposed. They 

therefore found no basis for issuance of an Airworthiness Directive. 

Status: Although the FAA response indicated that no further action would be taken, its 

research continued and resulted in fulfulling the intent of the recommendation by the 

issuance of AD-74-o9-o4. Therefore, the Safety Board classified safety recommendation 

A-73-56 as "Closed--Acceptable Action." 

Synopsis: On February 17, 1974, a Piper Seneca (PA-34-200) crashed near Taos, New 

Mexico. The Safety Board's investigation disclosed that the four standard passenger seats 

and one smaller passenger seat (7th seat) which were installed behind the pilot and copilot 

seats had separated from their attachments during the crash sequence and were found in a 

pile in the forward part of the cabin. The seats were attached to the floor by means of 

"quick disconnect" fittings so that the seats could be removed. Although the seatbelts 

were attached to the aircraft floor, none had been fastened around the empty seats. As a 

result of its investigation, the Safety Board made the following recommendations on June 

2, 1975, to the FAA: 
APPENDIX A -58-

Issue an Airworthiness Directive to require that an improved latching 

device be installed on all Piper aircraft designed with "quick disconnect" 

seat installations. (A-75-50) . 

On September 26, 1975, the FAA responded that it had undertaken a "study of the 

condition described in the recommendation. We have now come to the conclusion, after 

further investigation, that an unsafe condition may exist. Verification of this possibility 

and a determination of whether this is a maintenance or design problem will require a 

survey of actual installations of seats and attachments, evaluation of alternate designs, 

and operatiqnal practices. A plan of action will be completed by November 15, 197~. We 

will advise you of the action which will be taken." 

On December 5, 1975, the FAA stated that "an Airworthiness Directive, 

AD-75-24-22, Amendment 39-2422, was issued with an effective date of November 21, 

1975." 

. . 

Status: The Safety Board has classified the recommendation as "Closed--Acceptable 

Action." 

The Safety Board also recommended that the FAA: 

Amend 14 CPR 23. 785(f) to require dynamic testing of seats to insure 

more realistic protection of occupants from serious injury in a minor 

crash. (A-75-51) · 

On September 26, 1975, the FAA responded that it "is unable to amend 14 CPR 

23. 785(f) to require dynamic testing unless realistic criteria are established. Necessary 

data are now being obtained by full scale controlled crash tests being conducted at 

Langley Research Center. In addition, we are conducting seat/occupant tests at NAFEC 

and are establishing computer capability through mathematic modeling at our Civil 

Aeromedical Institute at Oklahoma City. When realistic criteria are established, 

regulatory action will be taken." 

On November 9, 1978, the FAA stated that "in addition to the various research and 

development contracts in support of the general aviation crashworthiness program, we are 

' in the process of developing a Notice of Proposed Rulemaking to amend TSO-C39a for 

seats. We expect to complete this project by the end of 1979." · 

On May 11, 1981, the FAA stated that '' Simula, Inc., is currently under contract to 

the FAA ·to complete and validate the single occupant, seat-restraint mathematical 

model. A draft report from Simula is due in September 1981. Following our review and 

incorporation of any changes, the final report will be available for .printing during 

December 1981. The model's ability to predict seat-occupant-restraint system r~action to 

a crash pulse will be validated by comparison with test results obtained by· the Civil 

Aeromedical Institute." 

Status: The Safety Board has clasSified safety recommendation A-75-51 as 

"Open--Unacceptable Action. 11 . 

Synopsis: On December 2, 1976, a Beech Debonair crashed near Glenville, New York. The 

airplane ·cabin remained structurally intact, providing a. survivable environment. 

However, the pilot was killed when he struck the control yoke; a broken rib punctured the 

pilot's heart. The Safety Board's investigation disclosed that seats did not fail and that, 

had the pilot been wearing a shoulder harness, upper torso rotation would have been 
(:t : .i..:; 

I \j 

-59 APPENDIX A 

reduced and the thoracic injury would have been prevented. Safety Board investigations 

of ~hree other general aviation aircraft accidents provided evidence which supported the 

effectiveness of shoulder harnesses in preventing occupant injury in small airplane 

accidents. 

On June 16, 1977, the FAA amended 14 CFR 23 and 91 to require the installation 

and use of shoulder harnesses on small general aviation aircraft. The amended 

airworthiness standards of 14 CFR 23 now require that front s~ats of general aviation 

aircraft be equipped with approved safety belts and shoulder harnesses and the amended 

operating and flight rules of 14 CFR 91 require that shoulder harnesses be installed at 

each front seat location and be worn during takeoff and landing. These regulations, which 

became mandatory for flight crewmembers on all aircraft manufactured after July 18, 

1978, represented a notable improvement to occupant safety. However, because the 

Safety Board believed that occupants of. the then existing fleet of fixed-wing general 

aviation aircraft--over 164,000 active airplanes--would be denied the level of protection 

affored the occupants of aircraft manufactured after July 18, 1978, it recommended on 

December 8, 1977, that the FAA: 

Amend 14 CFR 23.785 to require installation of approved shoulder 

harnesses at all seat locations as outlined in NPRM 73-1. (A-77-70) 

Amend 14 CFR 91.33 and .39 to require installation of approved shoulder 

harnesses on all general aviation aircraft manufactured before July 18, 

1978, after a reasonable. lead time, and at all seat locations as outlined 

in NPRM 73-1. (A-77-71) . 

~.· On February 8, 1978, the FAA responded that it had considered the proposal in t"W NPRM 73-1 and that "it was not considered supportable in the rulemaking process and the 

Board has provided no new information to justify further rulemaking action." In a 

February 15, 1979 letter, the FAA stated that ''based on the information available to the 

FAA at the time of their decisions on those amendments, the agency determined that a 

shoulder harness retrofit requirement was not appropriate. Further it was also believed 

that delethalization of light aircraft cabins would be preferable to a requirement that all 

seats be equipped with shoulder harnesses." The FAA stated, however, that it would 

reconsider its earlier decisions regarding the issues and would advise the Safety Board on 

its decision. 

On March 28, 1980, the FAA advised the Safety Board that it had completed a 

survey of shoulder harnesses in small airplanes, that it was proceeding with regulatory 

analysis, and that upon completing of the analysis, it would provide the Safety Board with 

a detailed response. 

Status: The Safety Board has classified safety recommendations A-77-70 and -71 as 

"Open--Unacceptable Action." 

Synopsis: On September 2, 1978, an Antilles Air Boats, Inc,., Grumman 21A, struck the · 

water while on a passenger flight from St. Croix to St. Thomas in the Virgin Islands. The 

aircraft broke apart and the captain and 3 of the 10 passengers drowned. As a result of 

its investigation, the Safety Board recommended on August 24, 1979, that the FAA: 

Amend 14 CFR 135 to require all aircraft conducting passenger service 

under Part 135 in any overwater operations be equipped with approved 

flotation-type seat cushions, and to require aircraft conducting extended 

overwater operations to also be equipped with an approved life· preserver 

equipped with an approved survivor locator light. (A-79-67) 
APPENDIX A -=60-

On June 15, 1981, the FAA Administrator responded that he had directed his staff to ()·~~. 

assemble operational statistics regarding survival aids in waters landings, analyze the j) 

statistics, and present him with a summary of alternative means to mitigate those risks. 

The Administrator also stated that his staff would also provide a detailed estimate of the 

costs of each .alternative action, considering all relevant data and recommenda-tions from 

the Board. 

Status: The Safety ·Board has classifed safety recommendation A-79-67 as 

"Open--Acceptable Action." 

Synopsis: The Safety Board's investigation of the Rocky Mountain Airlines DeHavilland 

DHC aircraft accident near Steamboat Springs, Colorado, on December 4, 1978, 

illustrated the need for survival training for crewmembers and for the installation of 

shoulder harnesses on crew seats. As a result of its investigation of this accident, the 

Safety Board recommended on September 6, 1979, that the FAA: 

Strictly enforce the compliance date for the istallation of shoulder 

harnesses as required by 14 CFR 135.171. (A-79-70) 

On December 5, 1979, the FAA responded that "this agency's action of granting 

certain operators extensions to the shoulder harness requirment under Part 135 is a logical 

solution to a supply problem. We are not aware of any abuses by operators in delaying the 

installation of shoulder harnesses in their aircraft." 

In an April 29, 1981 letter, the FAA stated that "all requests for extension of the 

compliance date were necessitated because of nonavailability of shoulder harness kits by· 

vendors of manufacturers prior to June 1, 1979. The letter further stated that the FAA 

had conducted a spot check with several regional venQ.ors and had found that air taxi 

operators granted extensions were in compliance with 14 CFR 135.10. 

Status: The Safety Board has classified safety recommendation A-79-70 as 

"Closed--Acceptable Action. n 

Synopsis: A special study conducted by the Safety Board on "General Aviation Accidents: 

Post Crash Fires and How to Prevent or Control Them" showed that postcrash fires 

occurred in approximately 8 percent of the 22,002 general· aviation accidents which 

occurred between 1974 and 1978. About 59 percent of those accidents involving postcrash 

fire resulted in fatailities. However, fatalities were involved in only 13.3 percent of those 

accidents without fire. As a result of its special study, the Safety Board recommended on 

September ,9, 1980, that the FAA: 

Amend the airworthiness regulations to incorporate the latest technology 

for flexible, crash-resistant fuel lines, and self-sealing frangible fuel line 

couplings at least equivalent in performance to those used in recent FAA 

tests and described in report No. FAA-RD-78-28 for all newly 

certificated general aviation aircraft. (A-80-90) 

Amend the airworthiness regulations to incorporate the latest technology 

for light weight, flexible, crash-resistant fuel cells at least equivalent in 

performance to those used in recent FAA tests and described in report 

No. FAA-RD-78-28 for newly certificated general aviation aircraft 

having nonintegral fuel tank designs. (A-80-91) 

€ 

' 
~~(· •' 

-61- APPENDIX A 

Require after a specified date that all newly manufactured general 

aviation aircraft comply with the amended airworthiness ·regulations 

regarding fuel system crashworthiness. (A-80-92) 

Fund research and development to develop the technology and 

promulgate standards for crash-resistant fuel systems for general 

aviation aircraft having integral fuel tank designs equivalent to the 

standards for those aircraft having nonintegral fuel tank designs. 

(A-80-93) 

Assess the feasibility of reqUirmg the installation of selected crash 

resistant fuel system components, made available in kit form from 

manufacturers, in existing general aviation aircraft on a retrofit basis 

and promulgate appropriate regulations. (A-80-94) 

Continue to fund research and development to advance the 

state-of-the-art with the view toward developing other means to reduce 

the incidence of postcrash fire in general aviation aircraft. (A-80-95) 

On December 8, 1980, the FAA responded that it believed that the recommendations 

·"merit consideration, but will require indepth investigation with regard to effectivity and 

feasibility. A project has been established · to consider the substance of these 

recommendations." 

Regarding recommendations A-80-90 through -92, the FAA responded on October 

15, 1981, that it. concurred with the intent of the recommendations and that it had 

initiated a preliminary effort to study the impact of actions associated with 

implementation of these recommendations. The FAA stated that if its studies and 

evaluations "indicate the potential benefits to society outweigh the potential costs of 

implementation, the FAA will further consider these recommendations and or appropriate 

alternatives for accomplishing the intent of the recommendations." 

Status: The Safety Board has classified safety recommendations A-80-90 through -92 as 

"Open--Acceptable Action. 11 • 

Regarding safety recommendation A-80-93 and -95, the FAA responded that 11a 

crashworthiness investigation team specializing in the collection of precise accident and 

injury information is being formed. Research and development efforts will be undertaken 

depending on the results of the teams's findings. Any such programs will include a . cost/benefit analysis to assure that the cost of installing crash-resistant tanks and fittings 

are commensurate with expected safety improvements." 

On October 15, 1981, the FAA stated that it concurred in the intent of safety 

recommendation A-80-93 and -95. "Research and development efforts will be dependent 

upon the results of a review of general aviation accident data currently underway. We are 

placing a high priority on this review and will continue to keep the Board informed of our 

efforts in this regard!' 

Status: The Safety Board has classified safety recommendations A-80-93 and -95 as 

"Open.,--Acceptable Action." 
APPENDIX A -62-

Regarding safety recommendation A-80-94, the FAA responded on October 15, 1981, 

that it had completed an evaluation of this recommendation. "We have concluded that it 

is not feasible to require the retrofit of existing general aviation airplanes with selected 

crash resistant fuel system components, such as crash resistant fuel cells. We find that 

the total economic impact associated with the costs for engineering, recertification, 

parts, and installation would be prohibitive for the large number of general aviation 

airplanes presently in. operation. In consideration of the necessary supply of parts for 

these airplanes, coupled with the massive and complex logistics that would be required, 

we estimate that it would require decades to accomplish a retrofit program." 

Status: The Safety Board has classified safety recommendation A-80-94 as 

"Open--Acceptable Action." 

Synopsis: On December 17, 1980, the Safety Board completed an assessment of the 

adequacy of occupant protection in general aviation aircraft during a crash. The study 

was conducted because of the Safety Board's longstanding concern that a majority of 

serious and fatal injuries which occur annually in these aircraft should be preventable. 

The Safety Board's report reviewed accident investigation findings, crashworthiness 

research and studies, and the regulatory requirements to assess the adequacy of occupant 

protection during general aviation conditions which should be survivable. 

.. 

As a result of the special study, the Safety Board recommended that the FAA: 

Require that those general aviation aircraft manufactured to include 

attachment points for shoulder harnesses at occupant seats be fitted 

with shoulder harnesses no later than December 31, 1985, and, in the 

interim, require this modification as a requisite for change in FAA 

registration. (A-80-125) 

Develop, in coordination with airframe manufacturers, detailed, 

approved installation instructions for installing shoulder harnesses at 

each seat location in current models and types of general aviation 

aircraft in which shoulder harness attachment points were not provided 

as standard equipment. Publish and provide these instructions to owners 

of these aircraft by December 31, 1982. (A-80-126) 

Require that those general aviation aircraft for which FAA-approved 

harness installiltion instructions have been developed be fitted with 

shoulder harnesses at each seat location no later than December 31, 

1985, and, in the interim, require this modification as a requisite for 

change in the FAA registration. (A-80-127) 

Extend the application of all newly established occupant protection 

provisions of 14 CFR 23 to all newly manufactured general aviation 

aircraft. (A-80-128) 

Revise 14 CFR 23. 785(j) to incorporate performance standards and test 

criteria to insure that an acceptable level of occupant safety is achieved 

through cabin "delethalization." (A-80-129) 

Revise current standards for seat and restraint systems to incorporate 

needed crash worthiness improvements identified in FAA research project 

reports. (A-80-130) 

Establish standards for the dynamic testing of occupant protection 

devices required in general aviation aircraft. {A-80-131) 
I \ I \ ~ 

~;: j.? 

w .. ;~ \ ~ 

l 

t 

f 

! 

I/~ 

r ·w 

-63- APPENDIX A 

On April3, 1981, the FAA acknowledged receipt of.the recommendations. 

Status: The Safety Board has classified safety recommendations A-8.0-125 through 

A-80-131 as "Open--Response Received." 

Synopsis: On February 26, 1980, a Cessna Model 172K (XP) crashed during normal 

takeoff from the Eagle Creek Airport near Indianapolis, Indiana. The pilot, a commercial 

flight instructor and the only occupant of the aircraft, was killed. According to 

witnesses, the aircraft pitched up to a steep nose high attitude, about 60° or 70°, and the 

sound of the engine power reduced abruptly from takeoff power to idle. The aircraft then 

pitched down and rotated about 160° to the left before crashing on the edge of the asphalt 

runway. 

As a result of its investigation, the Safety Board recommended on February 24, 

1981, that the FAA: 

Issue an · Airworthiness Directive for Cessna aircraft in which 

interference between seats in the full forward position and door jambs 

currently exists requiring that the seat rail stops be positioned to permit 

proper seat locking in all seat positions. (A-81-15) 

Require the Cessna Aircraft Company to include an adjustment and 

locking check of front seats, belts, and shoulder harnesses on the "before 

takeoff" checklists applicable to all Cessna aircraft. This item should be 

included on new checklists as soon as possible. (A-81-16) 

Regarding safety recommendation A-81-15, the FAA responded on May 26, 1981, 

that an "analysis of the accident data on the Eagle Creek Airport crash has raised 

questions concerning the probable sequence of events that caused the actual crash. This 

has placed in question the part that seat slipping may have had in causing the crash. In 

order to complete our analysis of whether some Cessna seats may not lock in place 

properly because of interference with the door jamb, we are analyzing our service 

difficulty reports, inspections of Cessna production aircraft, and some additional. data 

supplied by the Board on other accidents where slippage of the pilot's seat was determined 

to be a causal element. 11 

Status: The Safety Board has classifed safety recommendation A-81-15 as 

"open--Acceptable Action." 

Regarding safety recommendation A-81-16, the FAA responded on May 26, 1981, 

that "in view of our comments on safety recommendation A-81-15, we believe it prudent 

to withhold any decision or action on this safety recommendation until we have completed 

our analysis on the issues surrounding any seat problem that may exist." 

Status: The Safety Board has classified safety recommendation A-81-16 as 

"Open--Acceptable Action." · 

Synopsis: On August 28, 1970, the Safety Board forwarded a letter to the FAA suggesting 

that "it is time to take a new look at minimum standards as they are applied in the 

general aviation crash safety field." In the letter, the Safety Board drew attention to the 

difference in crash safety philosophy employed by the FAA and the safety philosophy 

adopted by its sister agency responsible for automotive safety. The Safety Board 

recommended that the FAA reevaluate its position on m1mmum general aviation 

crashworthiness standards, considering at least the five specific recommendations 

included in the letter. 
APPENDIX A -64-

The Safety Board recommended that: 

(Part 1) Shoulder harnesses should be required on all general aviation· 

aircraft at the earliest practical date. 

(Part 2) Delethalization of aircraft interiors - Suitable energy-absorbing 

padding should be required on all interior structures to protect 

occupants. 

(Part 3) Dynamic testing of aircraft seats should be required. 

(Part 4) Emergency landing conditions - Regulatory action be initiated to 

raise the "minor crash landing" inertia forces of FAR 23.561 to a level 

comparable to those produced by a moderate-to-severe crash landing. 

(Part 5) Crash fire protection - Fuel tanks and fuel systems should be 

designed to minimize the spillage of fuel in moderate to severe crashes. 

(CY-70-42) 

, On September 3, 1970, the FAA responded that they were "preparing a Notice of 

Proposed Rulemaking on the subject of this recommendation and that its staff will be in 

touch with the Board's technical personnel." The FAA enclosed a copy of its Disposition 

of Petition re. Ralph Nader's Crashworthiness Petition. 

On November 7, 1972, the FAA indicated that an NPRM covering parts Nos. 1 and 2 

of the recommendation would be released before the end of the year. Regarding parts 

Nos. 3, 4, and 5, the FAA indicated that there may be need for improvements in those 

areas, but the information presently available was not sufficient to support rulemaking 

action. 

It took the FAA 7 years to implement the recommendation. Safety Board followup 

action included responses to NPRM 73-2 and FAA's Notice No. 7 4-3, Airworthiness 

Review Program. Evaluation of implemented action on Part 23 and Part 91 are now 

amended to require the installation of shoulder harnesses for the front seats of all small 

airplanes manufactured after July 18, 1978. Crewmembers occupying seats with required 

shoulder harnesses must have them fastened during takeoff and landing. The requirement 

is not retroactive to previously manufactured small planes. Part 23 was amended with the 

following paragraph: 

The cabin area surrounding each seat, including the structure, interior 

walls, instrument panel, control wheel, pedals, and seats, within striking 

distance of the occupants's head or torso (with the safety belt fastened), 

must be free of potentially injurious objects, sharp edges, 

proturberances, and hard surfaces. If energy absorbing designs or 

devices are used to meet this requirement, they must protect the 

occupant from serious injury when the occupant experiences the ultimate 

inertia forces prescribed in Section 23.56l(b) (2). 

Status: The Safety Board has classified safety recommendation CY-70-42 as 11Closed--Acceptable Action. 11 Part 4 of CY -70-42 was reiterated with the issuance of 

safety recommendations A-80-125 through -131. 
\ -65-

APPENDIXB 

NTSB EXPANDED ACCIDENT/INCIDENT REPORT 

(NTSB FORM 6120.4) 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

1 D ACCIDENT 

3 Aircraft Registration Number 4 Flight NUITiber 

2 D INCIDENT 

For collision betw&en 

aircraft, enter reg. no. 

and fit. no. for other aircraft 

2 NTSB Accident/Incident Number 

2 0 FAA DELEGATED 

5 Aln:raft Regiatnltlon Number I Flight Number 

7 Clly/Piace 9 Zip Code (Firs/ S numbers only) 10 Accident Slllt Elevation 

FeetMSL 

11 Date of Accident 

(Nos. forM, D. Y) 

I, I I I. I 

Attach additional pages if necessary 

I II " I 14 TlmeZoM 

16 Addlllo.nal Persons Participating In !his Accidentllncldentlnveatlgatlon (Name, address. affilialion, attach additiOnal pages if necessary) 

17 Date 

(Nos. forM. D. YJ 
APPENDIX B -66-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT !INCIDENT 

Airport/ Approach/Landing Information 

25 Alrpo<l Name 26 Airport 27 Accident Location 28 Distance From Airport Center 29 D lrec:tlon From Airport 

ldentlflef 1 0 Off airporVairstrip (Nearest SMJ L!....J ' Magnetic 

AOtherW 2 0 On airport Uj SM A Other W 3 0 On airstnp A Other W A Other W 

30 VFR Approach/Landing (Multiple entry) 31 Type Instrument Approach Flown 1 Multiple entry) 32 Runway Usad ldendfier 

1 0 None 1 0 None l..L...LJ 2 t:J Traffic pattern 2 0 AOF!ND8 11 0 LOA A Other w 3 0 Straight-in 3 0 VOR/TVOR 12 0 ASR 

4 0 Valley/terrain lollowing 4 0 VOR/DME 13 0 PAR 33 Runway Length 

50 Touch and go 50 TACAN 14 0 Sidestep I I l I I I Feet 

6 0 Full slop 6 0 !LS-complete 15 0 Visual A Other W 

7 0 Stop and go 7 0 tLS-Iocalizer 16 0 Contact 34 Runway Width 

8 0 S1mulated forced landing 8 0 ILS-bac~course 17 0 Circling ~Feet 

9 0 Forced landing 9 0 RNAV 18 0 Practice A Other L.J 10 0 Precautionary land1ng 10 0 MLS A Other w A Other W 35 Airport Elevation 

I I I I I I Ft. MSL 

A Other w 

36 Runway/Landing Sur1ace 37 Runwayfl..anding Surface Status 

1 0 Macadam t 0 Dry 11 0 Water-glassy 

2 0 Asphalt 20 Wet 12 0 Rubber deposits 

3 0 Concrete 3 0 Ice covered 13 0 Soft 

4 0 Gravel 4 0 Snow-dry 14 0 Rough 

50 Dirt 50 Snow-wet 15 0 Slush covered 

6 0 Grass/turf 6 0 Snow-crusted 16 0 Holes 

7.0 Snow 7 0 Snow-compacted A Other w 

8 0 Ice 8 0 Vegetation 

9 0 Water 9 0 Water-calm 

A Other w 10 0 Water-choppy 

38 If accident/incident occurred during taxi takeoff, approach. landing or appropriate maneuvering phase of operations. check 

here Oand complete airport supplement. 

Aircraft lrifonnation .. . ,, ": ~-. " - " - -

.. 39 Aircraft Manufacturer 40 Aircraft Model/Series 41 Serial No. 42 Certltlealad Maximum 

GrouWelght 

A Other w A OtherW 

43 Type of Aircraft 44 Type Airworthiness Certificate 4S HomeBulll 

1 0 Airplane 5 0 Blimp.tdirigible Standard Special 1 0 Yes 6 0 Restricted 2 0 Helicopter 6' 0 Ultralight 1 0 Normal 7 0 Limited 2 0 No 

3 0 Glider 7 0 Gyroplane 2 0 Utility 8 0 Provisional A Other w 4 0 Balloon A Specify 3 0 AcrobatiC 9 0 Special flight 4 0 Tran~port 10 0 Experimental 50 Unknown A OtnerW 

NTSB Form 6120.4 !Rev 1.'831 Page 2 
-67- APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT /INCIDENT 

Aircraft lnform.llfon (continued):; ;• ~ : .. .. 4S Landing Gear f Multiple entry) 

1 0 Tricycle-fixed 4 0 Tailwheel-all retractable 7 0 Hull 10 0 Ski 13 0 High Skid A otherw 

2 0 Tncycle-retractable 5 0 Tailwheel-retractable mains a 0 Float 11 0 Ski/wheel 14 0 Body gear 

3 0 Tailwheel-alllixed 6 0 Amphibian 9 0 Emerg. float 12 0 Skid 15 0 Wing gear 

47 Ain:raft Damage 48 No. of Seats 49 Stall Warning System SO IFR Equipped 51 Icing Certification 

1 0 None l....J....tJ Installed 1 0 Yes 1 0 Yes 

2 0 M1nor A Other w 1 0 Yes 2 0 No 2 0 No 

3 0 Substantial 2 0 No A OtherW A Other LJ 4 0 Destroyed A Other w 

52 Engine Manufacturer 53 Engine Model and Series 54 Engine Rated HorMpoW91' 56 Engine Type 

A Otherw 1 0 Reciprocating-carburetor 

55 Engine Rated Thrust 2 0 Reciprocating-fuel injected 

_Lbs A.. Other L..J 3 0 Turbo prop 

57 Number of En!Jines 58 Type Maintenance Program 59 Type of Last Inspection 4 0 Turbojet 

w 1 0 Annual 1 0 Annual 50 Turbofan 

A Other LJ 2 0 100 hour 2 0 100hour 6 0 Turbo shalt 

3 0 AAIP/progressive 3 0 AAIP/progressive A OtherW 

4 0 Continuous a1rworthiness 4 0 Continuous airworthiness 

A Otherl..._j A Other L...J 60 Dale Last Inspection Performed 61 Time Since Inspection 62 Airframe T ot•t Time 63 Source of Maintenance Information 

1 Nos. for M. :J. Y 1 ~Hours I I I I I I Hrs. 1 0 Tach 4 0 Logbooks Records 

\ I I I I, I A Other w A Otherw 2 0 Flight 50 Estimate 

A Other W 3 0 Hobbs A OtherW 

Engme Time 

! /Hours) A Total Time B Time Since lnspec1ion c Time Since Major Overhaul D Other 

64 Engine No 1 I 65 Engine No 2 I 66 Hazardous Materials on Aircraft 67 Hazardous Material Spill/Factor Emergency Locator 1 2 A 

10 No 1. 0 Yes Transmitter (EL T) Yes No ! Other 

A 2 0 No 68 Installed 

B othe;w A Other w 69 Required 

70 Operated 

Operator Information ; -

71 Registered Alrcr•ll Owner 72 Address 

Name 

73 Operator ol Aircraft 1 0 Same as register!.d owner 74 Address 1 0 Same as registered owner 75 Operator Certificate No. 

A Name: A 

B dba A Other W 

c Other L.J B Other w NTSB Form 6120.4 rRcv 1 831 Page3 
APPENDIX B -68-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT/INCIDENT 

: "" 

~Operator lnfOI'I'IIIdlon (continued) ,_ ,~: . -~:···. , ;·~.: -~L ... .. 76 Operator Status ol This Aircraft 77 Pilot Status of This Aircraft 

1 0 Owner 4 0 Borrower 1 0 Owner 4 0 Borrower 

2 0 Lessee 5 0 Unauthorized 2 0 Lessee 5 0 Unautnorized 

3 0 Renter A Other W 3 0 Renter 6 0 Employee 

A Other W 

Type of Certificate(s) Held 78 None 0 (Go to block 82) 

79 Air Carrier Operating Cel11ficatl! 80 Operating Cl!l111icate 81 Operator Cl!rtlficale 

1 0 Flag carrier/domestic {121) 4 0 Large helicopter (127) 1 0 Aor travel club 1 0 RotorcraM-externalload operator (133) 

2 0 Supplemental 5 0 Commuter aor earner 2 0 Other operator of 2 0 Agricultural aircraft (137) 

3 0 All cargo (418) 6 0 On-demand au taxi large atrcraft 

Regulation Flight Conducted Under 

82 Regulation FUghl Conducted Under 

1 0 14 CFR 91 {only) 4 0 14 CFR 125 7 0 14 CFR 135 A Spec•ty 

2 0 14CFR91D 50 14CFR127 sO 14 CFR 137 

3 0 14 CFR 121 6 0 14 CFR 133 9 0 14 CFR 129 (Fore;gn /lag) 

Type of Flight Operation Conducted 

(Complete 83, 84, and 85 ONLY if flight was a revenue operation conducted under 121. 125, 127, 129, 135) 

83 84 85 

1 0 Scheduled 1 0 Domestic 1 0 Passenger 3 0 Passenger/cargo 

2 0 Non-scheduled 2 0 International 2 0 Cargo 4 0 Mail contract ONLY 

(Complete 86 ONLY if flight was NOT a revenue flight conducted under 121. 125. 127, 129, 135) 

86 

1 0 Personal 4 0 Executwe/corporate 7 0 Other work use 10 0 Positioning 

2 0 Busmess 5 0 Aerial apphcat•on 8 0 Public use 

3 0 Instructional (Including air earner training) 6 0 Aenal observation 9 0 Ferry A Specify 

t~·nformatlon .. 

;' ~' .. ·· · 

· ..,;~_}. :·: .. "· ,:;:,;t::; >r~; "·'""r'-.:~ ~ ~~-;.,; ,:s?{f&i~~Q~:2,ij;~.;~i::::·;~';:~~;;?~(:;},:1;;,.~:,.:.·." 87 Na1114!1 (Last. Firs/, lmllal) sa Pilot Certllicale No. 89 Street Address 

A Other w A Otherl_,J A Other w 90 City 91 State 192 Date of Bil1h 1 Nos. lor 93 Age 194 Sex I I I I I I I MD. Y) L,J Yrs 10 Male 

A Other l J w A Other L,_j A Otherl.J 2 0 Female 

95 Seal Occupied 96 Pl1nelpal Profession 97 Cerlificale(s) rMultrple entry) 

1 0 Lefl . 1 0 Pilot-civilian 7 0 Doctor/dentist 13 0 Farmer/rancher 1 0 Student 60 Flight Engineer 

2 0 Right 2 0 Pilot-military 8 0 Police 14 0 Ret~red 2 0 Pnvate 7 0 Military 

3 0 Center 3 0 Other-military 9 0 Student A OlherW 3 0 Commerc1al 8 0 None 

4 0 Front 4 0 Aircraft mechanic 10 0 Clergy 4 0 Alfhne Transport 9 0 Foreign 

50 Rear 50 Business 11 G Teacher 5 0 Flight Instructor A Other LJ A Otherl,J 6 0 Lawyer 12 0 Engineer (Complete block 101) 

NTSB Form 6120.4 I Rev 118.lJ Page4 
~}···;' lY~ .. 

r. 

l· 

l 

,, 

H 

r ,. 

,. 

t~ 

0 . 

' 

-69- APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT/INCIDENT 

!!e:=~.::,~·~:~!~~~~:~~;?r~:r~~:~:~;~~:r .. 

.. 

98 Ratings-Airplane 99 RotorcraiVGIIder/L TA 100 lnatrumenl Rating 101 Instructor Rating(s) 

1 0 Single engine land 1 0 Helicopter 10 None 10 Airplane SE sO Instrument airplane 

2 0 Multiengine land 2 0 Gyroplane 20 Airplane 20 Airplane ME 70 Instrument helicopter 

3 0 Single engine sea 3 0 Airship 30 Helicopter 30 Helicopter 

4 0 Multiengine sea 40 Free balloon 40 Gyroplane 

S 0 Ghder sO Glider 

102 Ground Instructor 103 Rating/Endorsement This Aircraft 104 Months Since Check/Endorsement 105 Biennial Flight Review 

10 Basic 1 0 Yes w Months (Or equivalent) 

20 Advanced 20 No (Go to block 70S) A Other w 10 Yes 

30 Instrument A Other w 20 No 

40 None A Other L.J 

106 Months Since Last BFR 107 BFR (Or equivalent) Aircraft Make/Model 108 Medical Certificate 109 Medical Certificate Validity 

w Months A Make tO Class 1 1 0 Valid medical-no waivers/llmitat•ons 

A Other LJ B Model 20 Class 2 20 Valid medical-with waivers/limitations 

COiher W 30 Class 3 30 Non valid medical lor lhis flight 

A Other L..J 40 Expired 

sO ·No medical certificate 

110 Date of Las! Medical (Nos. lor M.D. Y) 111 Medical limitation for 112 Medical waiver tor A Other L.....J 

I I I I I I I 1 0 Vision 10 Vis•on 

A Otherl.J A Specify 20 Heanng 

A Specify 

8 tither L..J 8 Other L..J 113 Statement of Demonstrated Ability 114 Correcting Lenses (Multiple entry 1 115 Source ot Pilot Flight Time 

1 0 Yes 1 0 Required to be 1n possession 10 Pilot log sO Estimate 

2 0 No 2 0 Required 10 be worn 2 0 Company sO Relative 

A otherw 30 Worn at time of accident 3 0 FAA A Other w 

A Other LJ 4 0 Operator 

c 

A • c D E F lnsuument G H I J K 

Flight Time AUA C lhrs Mall(- Ar'Piane Arrprane Nrght Aclua! Srmulateo Rotorcrah G110er LrgnTe• Other 

& Mooe• Srng1e E ngrnp Mullrengrne Tl'\8~"· Art 

135 Total Time 

136 Pilot in Command (PIC) 

137 Instructor 

138 This Make/Model 

139 Last 90 Days I I 140 Last 30 Days I I I 141 Last 24 Hours I I I 142 Landings-Last 90 Days All AlrcraH 144 Landings-Last 90 Days 146 Person at Controls 147 Degree of Injury 

-This Make/Model ~ 1 0 Pilei in command sO No one 1 0 None ~Day A Other W l...t__._j Day A Other 2 0 Second p1lot A Otherl........ 2 0 M.no• 143 Landings-Last 90 Days All Aircraft 145 Landings Las190 Days 3 0 Both pilots 3 0 Senous -This Make/Model W ~Night A Other w L..__,_j Night A Other 4 0 Non-pilot 4 0 Fatal 

148 Seatbelta Available 149 Seatbelts Used 150 Shoulder Harness Available 151 Shoulder Hamess Used 152 Autopsy Pertormed ( Thrs piloli 

1 0 Yes 1 0 Yes 10 Yes 1 0 Yes 10 Yes 

20 No 20 No 20 No 2 0 No 20 No 

A OtherW A Otherw A Other L...J A othe•w A Other L...J 

NTSB Form 6120.4 tRev 1 8J1 Page -

o 

___________ ..... .. ........ ----------
J • 

I 

I 

[ 

I 

APPENDIX B -70-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT/INCIDENT 

Pilot Information (continued) 

153 Toxicology Performed ( Thrs pilot) 154 Second Pilot 

1 0 Yes A Other w 1 0 Yes rComp/ete ;econd pilot supplement) 

2 0 No 2 0 No 

Flight Itinerary Information 

155 Last Departure Point (Multiple entry 1 157 DesUnallon ( Mullipte entry) 158 Flight Plan Filed 

1 0 Same as accidentJincident location or 1 0 Same as acc~dentiinclden~ location or 10 Vrsual Fhght Rules (VFRJ 

A Airporl identifier 2 0 Local flight 20 Instrument Flight Rules (IFRJ 

B Cuy;Ptace A Arrport loentrher 30 VFR!IFR 

C StateW D Other w B Cily/Piace --·· 40 Company iVFR) 

156 Time of Departure estate W sO Military (VFR) 

A Time~ C Other L.J 0 Other w sO None 

B Time zone~ A OtherL.J 

159 type of Clearance 160 Air11pace 

tO None 1 0 Uncontrollecl 8 0 Stage II TRSA 15 0 Warnmg area 

2 0 Spec•al VFR 2 0 Controlled 9 0 Stage Ill TRSA 16 0 FAR 93 (Spec•al air traffic areas) 

3 0 IFR 3 0 Airport trallic area 10 0 Prohrblted area A Other w 4 0 Special IFR 40 Control zone t 1 0 Restricted area 

sO VFR on top 5 0 Airport advisory area 12 0 M!lrtary Operating Area ;MOA) 

60 Cruise 6 0 Positive con trot area 13 0 Student Jet T rainrng Area 

A Other LJ 7 0 Termrnal control area 14 0 Demo Area 

161 Control Area 162 Route 163 Two Way Communications Established 

1 0 Vrctor arrway 1 0 Standard instrument departure 6 0 IR route (military) 10 No 

2 0 Jet airway 20 Standard te(m1na1 ar nval 70 SR route (military)' 2 0 Yes 

30 Control airway 3 0 Area navigatron sO Refuelrng route (military) A Facility identifier 

40 Colored arrway 4 0 Drrect A OtherL..J ---- A Other LJ 5 0 VR route (military) B Other w 

Aln::ndt Loading lnfonndon 

164 Fuel on Board at Takeoff I Multiple entry) 165 Fuel Types 

1 0 Estrmated 1 0 80!87 50 Kerosene 90 Mixture 

2 0 Verified 20 100 low lead 6 0 JP3.4.5.6 100 Automotive 

A Gallons or 30 100<130 7 0 Je-t A 11 0 Anti ice additive added (If known) 

B Pounds 40 115!145 8 0Jet6 A Other w C Other [..J. J 166 Airerafl Weight at Takeoff 1 Multiple entry 1 167 Aircraft CG at Takeoff 1 Multrple entry 1 

1 0 At or below max cert. gross takeolt werght 40 Verified 1 0 Wrthrn limits 4 0 Exceeded lateral limit 

20 Above ma.x certificated gross takeoff we1ght A Other w 2 0 Exceeded fwd limrt 5 0 Estrmated 

3 0 Estimated 3 0 Exceeded aft limit 6 0 Veritred 

A Other w 168 Aircraft Weight at Accident (Multiple entry 1 16!1 Alrcralt CG at Accident (Multiple entry I 

1 0 Same as takeolf sO Verif1ed 1 0 Same as takeoff sO Exceeded lateral lrmit 

2 0 At or below max cert. gross takeoff weight A Other L.J 2 0 Within lrmrts eO Eshmated 

3 0 Above max certifrcated gross takeolf werght 30 Exceeded fwd limit 70 Verified 

4 0 Estimated 4 0 Exceeded aft limit A Other w 

NTSB Form 6120.4 rRt" t e.<J Page 6 

• ,, 
-71- APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT /INCIDENT 

_.Aircraft Loading lnf(lf'ln8tlon (continued) 

170 Load Description 174 Simulated Instrument Flight 175 VIsion Restricting Device Used 

1 0 None i 0 Parachutists t 0 Yes 1 0 Yes 

2 0 Passengers 8 0 Water 2 0 No 2 D No 

3 0 Cargo 9 •0 Chemical A Other l J A Other l J 4 0 Towing glider 10 0 Livestock 176 Parachute Required 177 Parachute Used 

5 0 Towing banner 11 D mega! cargo t DYes 1 0 Yes 

6 0 Other external A OtherLJ 20 No 2 D No 

A Otner L J A Other l.1.J 

. Meterologlcallntormatlon 

180 Source of Weather Briefing (Multiple entry I 181 Method ol Briefing (Multiple entry/ 

t 0 No record of briefrng 6 0 Company t 0 In person 

2 0 National Weather Service (NWS) 7 0 Commercial weather service 2 0 Teletype 

3 0 Flignt Service Station sO TV!radio wea1her 3 0 Telepnone 

4 0 PATWAS (Pilot Automated TeL WX Answenng SVCI 90 Military 4 0 Aorcraft radro 

5 0 VRS (Voice Response System) A Other w 5 D TV1radio 

A Other w 182 Completeness of Weather briefing 183 Investigator's Source ol Weather 184 Weather Obeervallon Facility !Direct entry) 

1 0 Wealher not penment Information A Identifier ___ 

2 0 Full 1 D Pitot!Go to block 185) B Time of observalion zone __ 

3 0 Partial-limited by pilot 2 D Witness rGo to bloch t85) C Elevation teet MSL 

4 0 Partial-limited by brieler/lorecaster 3 0 Weather observation facility D Distance !rom accident site __ NM 

A Other w E Direction from accidenl site 'magnetic 

185 Basic Weather Conditions 186 Conditions of Light 187 Lowest Sky/Cloud Condition .188 Lowest Ceiling 

1 0 Visual Meteorological Conditions (VMC) 1 D Dawn 1 D Clear 1 0 None (Clear) 

20 Instrument Meteorological Condrtions (IMC) 2 D Daylight 2 D Scattered 2 0 Bro~en 

A OtherW 3 D Nrghl (Dark) 3D Thin broken 3 0 Overcast 

4 D Night (Bright) 4 D Thin overcast 4 0 Obscured 

189 VIsibility 190 Temperature 50 Dusk 5 0 Partial obscuralion A ---Feet AGL 

__ SM • F A OtherL.J A Feet AGL BOther w A ~er l J B Olher w 191 Dew Point 192 Wind (From) 193 Wind Velocity 194 Gusts 195 Altimeter Selling 196 Density Altitude 

--'F t 0 Variable 10 Calm t D None W.w..J··Hg Feel 

A Otherl.J A c. Magnetic A __ Kts A __ Kts. A Other w A Other w B Other W B OtherW B OtherLJ 

197 Restrictions to VIsibility 198 Type of Precipitation 

t D None 7 0 Ground log (GF) 1 0 None 7 0 Snow shower (SW) 13 0 Ice crystals (I C) 

2 0 Haze (H) 8 D Stowing spray I BY) 2 0 Rain (R) 8 D Drizzle (L) 14 0 tee pellet shower (IPW) 

3 0 Dust (D) 9 0 Blowing dust !BD) 3 0 Snow (5) 9 D Ice pellets (IP) A Other w 4 D Smoke (K) 10 D Blowing snow iBS) 4 D Hail (A) 10 0 Snow pellets (SP) 

5 D Fog (FJ 11 0 Blowing sand (BNI 5 D Rarn showers (RW) 1 t 0 Snow grarns (SG) 

6 D Ice tog (IF! A Other W 6 0 Freezing rain (ZRl 12 0 Freezing dnzzle tZL) 

200 Intensity ol Preeipllallon 201 Aircrafl Fire 202 Explosion 203 Damage lo Proparty 

1 D Light 1 0 None I 0 None 1 D None 5 0 Vehrcle(s) 

2 0 Moderate 2 D In-flight 2 D ln-lhgnt 2 0 Residence 6 0 Arrport facll•ty 

3 0 Heavy 3 0 On ground 3 0 On ground 3 0 Residential area 7 D Trees 9 D Wires!potes 

A Otr>erW A OtherW A OtherW 4 0 Commercial bldg 8 D Crops 10 0 Otner properly 

NTSB Form 6120.4 •R•·v 1 Ur Page 7 
APPENDIX B -72-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

ACCIDENT /INCIDENT 

::, .. ~~.P-'·· .·· ~.~?''·"·~: · ·· ... rt~~.L:i:.2.:~.· ~;~{$ll~~· .. ~~·;d .. ·<, .. ·.·. :,·. ···· ··· 

< : .... ,,.,, '.'';/:/, ;;::;, ·,;,;.' ·'';·~~;·', (i.<::: •.'·;j,·l~~~:--;;~;,;;,~~~· ·.:..;...· ~;;;..;·~··...;..;;. _____ -t 204 Pari Failure/Malfunction (Mullrp/e entry) 205 Incorrect Part (Multiple entry} 

1 0 None 3 0 Part/component #2 A Other W 1 0 None 3 0 Part/compdnent #2 A Other W 2 0 Part/component #1 4 D Part/component #3 2 0 Part/componenl # 1 4 0 Part/component •3 

I-:=-:-::-:-P::-a-r1~N_a_m_e _____ +-__ A_P_a_rll_c_om_po_n_e_n_t_•'---·t--•zc~mponen1#2 

205 ATA Code 

206 Manufacturer 

207 Mfg. Pari • 

208 Mig. Model • 

209 Serlalt 

210 Pari Condition 

211 Total Time 

212 TSO 

213 TSI 

214 Cycles T otsl 

215 Cycles Since Overhaul 

216 Cycles Since lnapectlon 

217 S..rYice Difficulty Repo.; or 

Mallunctlon/Defecl Repori 

Submllled 

I\ITSB Form 6120.4 1 Rnv 1 '1\:l; 

, 1 0 Yes 

I 

2 D No I 0 Yes 2 0 No 

C Part/Component #3 

--------------------

1 0 Yes 2 0 No 

PageS 
-73- APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

NTSB Accident/Incident Number 

Supplement !-Crash Kinematics ' '' · ·. · 

1 Accident Slle Geographic Coordinates -Latitude 

10 North A W W 

2 0 South B Other L..J 

3 Impact Sequen.,.._l Number .n sequence. Multrple entry. 1 

1 D None 7 D Ground 

2 D Rock face 8 D Dirt bank 

3 Ci Rigid structure 9 c::::J Scrub tree 

4 =:J Rocks to 1' diam. 10 CJ Trees/hmbs to 6" dram. 

50 Rocks 1'-2'diam. 11 c::::JTrees!limbs 6"-9" diam. 

6 D Rocks > 2' diam. 12 CJ Trees/limbs 9"·12" diam. 

4 Terrain At Principal Impact Point 

1 0 Wet cultivated soil 

2 0 Dry cultivated soil 

3 0 Dry packed clay 

4 0 Soggy swampy 

5 0 Packed snow 

6 0 Loose snow 

7 0 Concrete 

8 0 Asphalt 

9 0 Loose rock 

10 0 Dry sod 

5 Airspeed AI Impact (Enter d~rect or mark estimated range) 

1 0 0·15 6 0 75·90 11 0 210 plus knots 

2 Accident Site Geographic Coordinates-Longitude 

1 0 East 

2 0 West 

Trees/limbs 12" diam. and up 

Frangtble approach aid 

Non-frangible approach aid 

Submerged obstacle 

Vehicle 

Aircral! 

16 0 Ice 

17 0 Mud 

18 0 Sand 

19 D None 

A 

A L..J' L.J 

B Other LJ 

19 0 Runway light 

200 Water 

21c::::JWire 

220 Pole 

23 D Snow bank 

A Other W 

2 0 15-30 7 0 90-120 A Knots 

3 0 30-45 8 0 120-150 6 Other W A 

8 

__ Degrees 

Other W 4 0 45-60 9 0 150-180 

5 0 60-75 10 0 180-210 

7 Pitch Attitude AI Impact (Enter direct or mark est•mated range. 1 

Pitch Attitude Nose Down Angle With Honzon Nose Up Angle With Horizon 

1 0 Down I I ~ ¢ ~ ~ ~ ~- ~ '\\ 'l 2 0 Up D 75 0 60 0 45 0 30 D 15 D o 0 t5 0 Jo 0 45 D 80 0 1s 0 

A __ Qeg. 

~\\\\~~~~.PP.fif~ 90 0 75 0 60 0 45 0 30 0 t5 0 0 0 15 0 30 0 45 0 60 0 75 0 . 90 

v Roll Attitude At Impact !Enter direct or mark estimated range. 1 

Atrcraf1 Rolled Left Alfcraf1 Rolled Righi 

Roll 

1 0· Left 

~'"~~--- ..... ,....?'11 2 0 R1ght 

0105 0 120 D 135 0 1so 0 165 0 180 0 1ss 0 1so 0135 0 120 0 10s 0 

A ---Deg. 

~ /t ! . ,~-· ..¥ ~ ...- ~ ~ \.. ~ ' ~ 90 0 75 0 60 0 45 0 30 D IS 0 0 0 15 0 30 0 45 0 60 0 75 0 90 

NTSB Form 6120.4 Supplement I i1t83) 

B 

orOther L....J 

B 

orOther L..J 

Page 1 
APPENDIXB -74-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement !-Crash Kinematics (continued) 

9 Yaw A !Illude allmpacl (Enter direct or mark estimated range.) 

1 0 Nose left 

2 0 Nose nght 

A --~De9 

Alfcrafl Yawed Left Aircraft Yawed Right 

90 0 75 0 60 0 45 0 30 0 15 0 0 0 15 0 30 0 45 0 60 0 75 0 90 

or 

B Other 

a.;)).·). 1)}' I 
WI () 

I; 

l 

6 L 

'I 

NTS8 Form 612G.4 Supplement I (1183) 

-75-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Elevation View 

APPENDIX B 

'' 

'' 

3 
1.¥13 lidliifMiliNii?M 

APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

-76-

NTSB Accidentllnciden1 Number 

Supplement K-Occupant. Survival and Injury Information 

1 Seat No. 

A L.J B If Seat Unknown Enter 

Persons Name 

C Other l J 

2 Potlllon 

1 0 Pilot in command 

2 0 Second p•lot 

3 0 Other crewmember 

4 0 Passenger 

A Other W 

3 Age 

A L.Jvrs 

B Under 24 mos .. enter 

mon1hs W 

C OtherW 

4 Height 5 Weight 

--- Inches 

A Other W A Other 

Los 

w 

6 Injury tncte• 1 0 None 

7 Condition Prior to ACCident 

1 0 Smoker 

8 Phyolcany Handicapped 

10 No 

9 Seal Belt Adjustment 

1 0 Not fastened 

10 Shoulder Harness Adjustment 

1 0 Not faste~ed 

2 0 Minor 

3 0 Serious 

4 0 Fatal 

A Other L.J 

2 0 Language difficulty 

3 0 Pre-extsting d<sease 

4 0 Prothesis 

A Other W 

2 0 Blind 

3 0 Mobility impaired 

4 0 Deal 

A Other W 

2 0 Loose 2 0 Loose 

3 0 Snug 3 0 Snug 

4 0 T•ght • 0 r.gnt 

5 0 Seat not equipped 

A Other -l j 5 0 Not seated 

A Other W 11 Knew lmpacVAccidenl Coming 

1 0 Yes 

12 Braced lor Impact 

1 0 Yes 

13 Direction of Movement atlmpacll Multiple en1ry J 

2 0 No 

A Other W 

E•it Diagram 

CL Cockp•t 

1L 

2L 

3L 

! 16 Bt!efed on Emeogency Proc:edutes 

1 0 No 

2 0 Behlfe takeofl 

3 0 Before impacVaccident 

A Other W 

1 0 Forward 3 0 Upward 5 0 Left 

2 0 No 2 0 Rearward 4 0 Downward 6 0 Righi A OtherW 

A Other W 

Use following co<ies lor overnead 14 Exll Used tUse d•agram; 

hatches 

CR A Other L.J 

Cockpit 99 

1R 

Cat>m88 

2R 

Tailcone 77 

3R 

J 

17 Olllk:ully In Using E•ll 18 Escape Hampered 

1 0 Yes 1 0 Yes 

20No 20No 

A Other L.J A Olher W 

19 Evacuation Aided by 

1 0 Passenger 

2 0 Crew 

3 0 Bystander 

4 0 CFR personnel 

A Other L.J 

15 Escape Hampered by 

1 0 Not hampered 

2 0 Smoke 

3 0 Heat 

4 0 ln1unes 

50 Trapped 

6 0 Darkness 

7 0 Oebns 

8 0 DiSonentatiOn 

A Specify ---~ 

B, Other U 

20 Injured During Evacuation 

1 0 Yes 

2 0 No 

A Other W 

Complete this section if oxygen was used, 

21 Type of Equlpfi.ent 

1 0 Supplemental 

2 0 Portable 

A Other w 

NTSB Form 6120.4 SUpplement K (1183) 

22 Dlfflc:ully In Use 

10 Yes 

20 No 

A Other W 

23 Type of O•ygen SySiem 

1 D Solid state 

2 0 Gaseous 

A Spec tty --------- B Otner L.J 

Page 1 

I 

I 

) 
~ ""I li . I . . \ .. ' . 

'"'··."' 

-77- APPENDIX B 

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement K-Occupant, Survival and Injury Information (continued) 

Complete this section for accidents involving fire. 24 0 No fire involved (Go to block 29) 

25 Are First Sighted 1 Location) 26 Smol<e Mask or Gogglefl Used 27 Material of Clolh1!11 Wom 26 Exposu111 to HeaVFrlll 

1 0 Inside aircraft 10 No 1 0 Synthetic 1 0 Head/face 

2 0 Outside aircraft 2 0 Yes 2 0 Nonsynthetic 2 0 Arm(s) 

3 0 Both 3 0 Both 3 0 Fire resistant 3 0 Hand(s) 

A Other w 4 0 Difficulty in use 4 0 Mix-synthetic and nonsynthetic 4 0 Leg(s) 

A Other w A Other w 50 Torso 

60Feet 

A Other L..J 

Complete this section for accidents involving ditching/water impact. 29 0 No watenmpact (Go to block 36) 

A Available c Used E Familiar 

With Use 

G Problems 

In Use 1 Malfunctione<l WilhUse 

K Eqwpment 

Damaged FlotatiOn Dev1ces 

1 Yes 2 B No Other 1 Yes 2 No 0 Other 1 Yes 2 No F Other 1 ves 2 No H Other '1 s\2 No \J i Yes Other 1 Yes 2 No L 

Other 

i 

30 Lilerall !wi iw w w Wi L.J 

31 Vest-Inflatable w w w w! w L.J 

32 Vest-Non-Inflatable w w w L.J w w 

33 Cushion L..J iw w w LJ w 

34 TIITHI in Water 35 Rescued by 

A __ Hrs. 10 Boat 3 0 Helicopter 50 Swimmer 

B Mins. c Other L.J 2 0 Airplane 4 0 None A Other 

Occupantlnjuries-Comp/ele applicable parts for survivors and nonsurvivors. 

Items 36 thru 43 apply ONLY to flight crewmembers. For non crew members, go to block 44. 

36 Medication Prescribed 37 Medication Being Taken 38 Hours Since Taken 39 Medication Dosage 40 Time Since Last Meal 

1 0 No 1 0 No Hrs. ___ Hrs. 

A Yes !S{)IJCify: __ 1 A Yes(Specily: __ ) A Other w A Other w A Other w B Other w B Olher w 

41 Medication/Drugs Found 42 Location Medication/Drugs Found 43 Pre-exlaUng Disease Found at Autopsy 

10 No 1 0 On body 1 0 No autopsy performed 

A Yes !Specify: --1 2 0 In personal effect 2 0 None reported 

B Other LJ 3 0 In aircraft A Yes S{)IJCily: 

4 0 Outside aircraft 

A Other w 8 OtherW 

NTSB Form 6120.4 Supplement K {1183) Page2 
APPENDIX B -78-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement K-Occupant, Survival and Injury Information (continued) 

Results of Toxicological Analyses-Complete as applicable for survivors and nonsurvivors. 

44 Toxicology 

1 0 Not ordered 3 0 Ordered-perlormed 50 Embalmed 

2 0 Not ordered-perlormed 4 0 Ordered-not perlormed 6 0 Specimen not available/unsuitable for analysis A Other W A Test Results 

Substances 1 Positive 2 Negative 8 Other c Level of Substances Found 

45 Ethanol (Alcohol) 

46 CO (Carbon Monoxide) 

47 hb (Hemoglobin) 

46 HCN (Hydrogen Cyanide) 

List any additional tox1cotogtcal substances 

discovered below. 

A Substance 

Code 

49 L...__._j 

50 L.........J 

51 L.......LJ 

52 Lw.J 

53 L......J 

54 L.......J 

55 Lw.J 

56 L........J 

57 l........J.J 

58 L...__._j 

59 L.........J 

60 L........J 

61 Lw.J 

62 Lw.J 

B Level of Substances Found 

NTSB Fonn 612o.4 Supplemenl K (1/83) 

w Mg% 

w % Saluration 

w gm% 

Microgramrml 

Toxicological Substances/Codes 

Acetamenophen . . . 001 

Acetaldehyde . . . . . . . 002 

Acetone . . . . . 003 

Amoxapine . . . . . . . . . .. . . . . 004 

Amitriptyline ................ 005 

Amobarbital .' ................ 006 

Amphetamine ............... 007 

Benzoyiecgonine . 008 

Brompheniramine ........•... 009 

Butalbital ................... 010 

Butabarbital .. .. . . 011 

Caffene . .. . . ............... 012 

Cannabin01ds ............... 013 

Chlorazepate .. . .. .. .. .. .. .. . 014 

Chlordiazepoxide ...........• 015 

Chlorphentermine ............ 016 

Clonazepam ................. 017 

Cocaine .................... 018 

Codeine .................... 019 

Desipramine .. . . . . .. . . . .. . . . . 020 

Diazepam ................... 021 

Dihydrocodeinone ........... 022 

Diphenhydramine .......•.... 023 

Diphenylhydantoin . . . . . . . . . . 024 

Doxepin . .. .. . .. .. • . . . .. .. . . 025 

Desall<ylflurazepam •......... 026 

Demoxapam ................ 027 

Ethcnlorvynol ....... , . . . . .. 026 

Flunitrazepam ............... 029 

Flurazepam . .. .. . .. .. .. . .. .. 030 

Fluphenazine .. . . .. . . . .. . . . . . 031 

Glutethimide ................ 032 

Haloperidol ................. 033 

Hexobarbital ................ 034 

Imipramine .................. 035 

Isopropanol . . . . 036 

Ketamine ... 037 

Li<locai ne . .. . . . . .. 036 

Mecloqualone . . . . 039 

Meperidine 040 

Mephentermine . . . . . . . . . . . . 041 

Meprobamate ............... 042 

Methanol .................... 043 

Methadone . . . 044 

Methamphetamine . . . . . . . . . 045 

Methaqualone . . . . . . 046 

Loxaplne . . . . . . . . .... 047 

Methylenedioxyam .... 045 

Phetamine .. . . .. .. . .. . .. . .. 049 

Methylphenidate .... 050 

Methypryton . . . • . . . .. . . . . . . .. 051 

Menthol . . . . .. . . • . . . . . . .. . .. . 052 

Morphine . . ................ 053 

Medazepam . . .. . . .. . . • . • .. .. 054 

Nicotine .................... 055 

Nortripl)lline . .. . . . . . .. .. .. • . . 056 

Oxazepam • . .. .. .. . . . . .. • .. . 057 

Pentazocine ................. 058 

Phenobarbital . : .. , .......... 059 

Procaine .................... 060 

Propoxyphene ............... 061 

Secobarbital ................. 062 

Thioridazine . . . . .. . . . . . ..... 063 

T emazepam . . . . .. . . . . . . . . .. . 064 

Nordiazepam ................ 065 

Pentobarbital . .. .. . . ........ 066 

Phencyclidine .. .. .. .. . .. . .. . 067 

Phendimetrazine ............. 068 

Prazepam ..........•. : .. 068 

Page3 

.

. ' •

•• 

•; ,. 

•.,. 

'.\!1\ ' • I 

' 
., 

' .. 

.J 

I 

r il ... 

-79-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

APPENDIX B 

Supplement K-Occupanl, Survival· ~nd Injury Information (continued) 0 ' 

63 0 For multiple extreme traumatic injuries, check box, and go to next applicable supplement. 

Occupant Injury Coding Chart (Complete for survivors and non survivors as applicable.) 

A Body Reg•on B Aspect C Lesron D A.I.S. §everity F G System/Organ 6 Injury Source 7 Source of Data 

64 

65 I 

66 

67 

68 

69 I 

I 

70 

11 

72 I I 

I 73 I 

Body Region - A 88 Injured aspect unknown 05 Uver Source ol Data - G 

99 Other 06 Nervous System 01 Head (Skull, scalp. ears) 07 Brain Ollicial 

02 Face (Forehead. nose. eyes. mouth) Lesion- C 06 Spinal cord 01 Autopsy records with or without 03 Neck (Cervical spone. C1-C7) 01 Lacera1 ion 09 Ears hospital/medical records 04 Shoulder (Clavicle. scapula. joint) 10 Arteries veins 02 Hospital/medical records 05 Upper limb (Whole arm) 02 Contusion 11 Heart 03 Emergency room records 06 Arm (Upper) 03 Abrasion 12 Spleen 04 Private or treating physicians 07 Elbow 04 Fracture 13 Urogenital 06 Forearm 05 Concussion 14 Kidneys Unollicial 

09 Wrist 06 Avulsion 15 Respiratory 10 Hand-lingers 07 Rupture 16 Eye 05 Lay coroner 

11 Chest (Anterior and posterior ribs) 06 Sprain 17 Pulmonary/lungs 06 E.M.S personnel 

09 Dislocation 07 Interviewee 12 Abdomen (Diaphragm and below) 10 Crush 18 Airway 06 Police 13 Back (Thoracsic spine T1·T12) 11 Amputation 19 Muscles 09 Other source 14 Back (Lumbar L 1-LS) 20 Integumentary 15 Pelvis-hip 12 Burn 21 Thyroid (Thyroid or other endocrine gland) 

16 Lower limb (Whole leg) 13 Fracture and dislocation 88 Injured. unknown system or organ 17 Thigh (Femur) 14 Severence (Transection) 99 Other 

18 Knee 15 Strain 

19 Leg (Balow knee) 16 Detachment (Separation) Abbrevtaled Injury Scate · E 

20 Ankle 17 Perforation (Puncture) 

21 Foot-toes 88 Injured unknown lesion 00 Not injured 

22 Whole bOdy 99 Other 01 Minor injury 

88 Injured. unknown region 02 MOderate injury 

99 Other Syalem/Organ - 0 03 Serious injury (Not life-threatening) 

04 Severe injury (Lite-threatening survival probable) 

Aapecl Of Injury - B 01 Skeletal 05 Critical inJury (Survival uncertain) 

02 Vertebrae 06 Maximum (untreatable) 

01 Right 03 Joints 07 Injured (Unknown severity) 

02 Lett 04 Digestive 88 Unknown if injured 

NTSB Form 6120.4 Supplement K (1/63) Page4 
i , 

APPENDIX B -80-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement K-Occupant, Survival and Injury Information (continued) 

Injury Soun:e List - F 

01 Windshiel<l 

02 Windshield frame 

03 Window 

04 Wondow frame 

05 lnstrumenl panel 

06 Side console 

07 Center console 

06 Conlrol s!ickicycl'c stick 

09 Collective 

10 Control yoke column 

1 t Throttle ouadranVIevers 

12 Rudder pedals , 

13 Ceiling 

14 Sidewall 

15 Floor 

16 fuselage framing; structure 

17 Table 

18 Seal 

19 Seatback tray 

20 Restraonts-seatbeiV!Iedown 

21 Restraints-shoulder harness 

22 Unsecured item(s) in cockpit 

23 Unsecured item(sl in cabin 

24 Other occupants 

NTSB Form 6120.4 SUpplement K 11/83) 

25 Ground/runway 

26 Unsecured seat(s) 

27 Outside Ob!ectls) entenng aircralt 

28 Galley item(s) 

29 Food/beverage item(s) 

30 Other interior ObJeCts 

31 Other extenor objects 

32 Evacuation shdetslide raft 

33 Escape rope/tape 

34 Escape inertia dev1ce 

35 Ejecled from aircraft 

36 Propeller/rotor blades 

37 Exterior a~rcraft surface 

38 Engone 

39 Wheel!lores 

40 Ground vehicle 

41 Toxic/noxiouS/Irritant fumes 

42 Fore/radiant heat 

43 Flying glass 

44 Door/hatches 

45 Acceleratoon torces 

46 Exposure 

88 Unknown 

99 Other 

PageS 
-81- APPENDIX B 

National Transportation Safety Board NTSB Accident!lncidenl Number 

FACTUAL REPORT 

AVIATION 

A Other L.J 1 0 Type certificate ( Al(/rame manufacturer 1 

2 0 Non-TSO 

5 Seat Type (Multiple entry 1 

1 0 Cockprt crew 

A 

B 

TSO (Specify! 

Other 

4 0 Fotdrng stowable 

A 

2 D Flight attenelant srngte jumpseat 

3 D Flight atlenaant double iumpseat 

S 0 Single passenger seat 

6 0 2 passenger seat unit 

7 0 3 passenger seat unit 

8 0 Sofa/Bench 

A Other L..J 

7 Total Seat Destruction iMultrple entry) 

1 D impact /Go to blocl< 30) 

2 D Fire (Go ro block 30; 

A Other W 

A Other W 

NTSB Form 6120.4 Supplement L (1/83! 

A 

8 Seat Anchored 

1 0 Bulkhead,wall 

2 0 Floor 

A Other L.J 

Other L..J 

9 Seal Primary Structure 

1 D Tube 

2 0 Sheet metal 

3 0 Composite 

4 0 Wood 

33 Restraint System Design 

1 0 2-point 

2 D 3-pomt 

3D 4-poont 

4 0 5-pomt 

A Other L.J 

1 0 Inside aircraft-attached 

2 0 Inside aircraft-separated 

3 0 Outsrde aircrall 

A Other 

11 Evidence of Fire/Heat Damage 

1 0 None 

2 0 Cushtonstcovers 

3 D Structure 

4 0 Restraims 

A 

34 Type Release/Buckle 

1 0 Metal to metal 

2 0 Fabriciputl thru 

A Specofy 

,B Ott.er W 

F 
APPENDIX B -82-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement L-Seat, Restraint System and Fuselage Deformation (continued) 

Aestraini System Desogn 

{ I I ~ -l Two Pomt 

Component 

Yes 

35 Lapbell 

36 Shoulder Harness 

37 Inertia Reel 

38 Tiedown Strap 

A 

Three 

~:4 Poont 

] .( ~ Four Poont 

A Installed 

2 B 

No Other 

L J 

w 

L J 

L J B 

Fire D~mage I EvidencEe of Use 

1 2 0 1 2 F 

Yes No Other 1 Yes No Other 

l Jl L j 

Li..J L....J 

L Jl Ld 

L Jl w c 

1 

Seat 

~ 

2 

Wall 

t L J ~ 

Ia.) Five Point 

G Location of Anchor Points 

3 I 4 

Floor Ceoling 

0 

5 

8ulkhea<J 

H 

Other 

w 

l J 

L J 

l J 

WebbongJStotchong Aestraont Attach Fottmgs SeattStruc1ure Attach Fitttngs 

Component "' Ol 

E "' 

Cl 

0 

z 

39 Lapbell I 40 Shoulder Harness I 

41 Other Damage Release Buckle 

1 0 Yes 

2 0 No A Other 

46 Fuselage Collapse Around This Seal 

1 0 None 

2 0 Collapse 

3 0 Dosmtegrationllnconerated 

1 

l 

0 

~ 

Cl "'

47 Interior Surface Damage To This Seat 

1 0 Yes 

2 0 No 

A Other W 

I 

I 

2 3 1 I 2 

I 

3 I 4 

" ,Ji "0 "' "0 

"' "' i "' i :a; 

'" E ,.. ,_- =" "" e "' -., - <ii Cl "'"' ., - ;;; ~ ·-= 8- -;::a. a. 

8:~ "' i 0 I ~ "'"' "' z 01 O..Cil 

I I 

I I 42 Other Damage Tie Down Strap 

1 0 Yes 

2 0 No A Other W 

5 1 2 3 

"' ~ 

"' ! 

~ 

~ "0 

~ "' e "' Cl ~ c 0 

z Cl "' co 

43 Other Damage Inertia Reel 

1 0 Yes 

4 

,._ji 

=" "'-

=~ O..<n "'"' 

2 0 No A Other 

48 Fuselage Collapse Measurements Around This Seal 

tEnter inches on drawing; 

Nose of AiC 

A Other c...~.J ' A r--;.;Fo:;;r.;.;w.;:;ar;.:d;_,._, 

·~ 

A 

01recuon of Detormat10n Fr---.,.....-, 

Th1s Seat 

5 

"0 

j§ "' 

"' a. 

"' "' 

Cabtn.- !ntenor 

Deformat10n Around Th1s 

Seat !Select cooes /rom 

list below) 1 I 2 I 3 

Forward j Rearward ; Left 

4 

Righi 

5 6 8 

Up I Down Other 

on Iso Code w i o.---....~-......,......., 

w on. 

cl linl 

51 Code 

52 Code 

Roof ( Downwara collapse 1 

53 Code Lt._! Nole: Arrow 1 1 shows dlfeCiton of displacement 

NTSB Form 6120.4 Supplement L (L83) Page2 

• ';l 

•

'1 

' y 
F 

r 

[' 

t. 

II'~ 

I 

r 

[ 

i 

I 

' i 

r 

i 

l 

I I; 

I 

i 

r 

r 

-83-

National Transportation Safety Board 

FACTUAL REPORT 

AVIATION 

Supplement L-Seal, Restraint System and Fuselage Deformation (continued) 

(COdes to be used in 50·53 above) 

01 Wlndsh•eld 

02 WindshieiCJ frame 

03 Window 

04 Window frame 

05 Instrument panel 

06 Side console 

07 Center console 

08 Control sucklcychc st1ck 

09 Collective 

10 Control yoke/column 

11 Throttle quadranVIevers 

12 Rudder pedals 

13 Ceiling 

14 Sidewall 

15 Floor 

NTSB Form 61211.4 Supplement L !1183) 

16 Fuselage framing/structure 

17 Table 

18 Seat 

19 Seatback tray 

20 Restra>nts-seatbeltitiedown 

2, Restraints-shoulder harness 

22 Unsecured item(s) 1n cockp<t 

23 Unsecured 1tem(s) in cab1n 

24 Other occupants 

25 Ground/runway 

26 Unsecured sea1(S) 

28 Galley <temls) 

30 Other interior objects 

44 Door'hatches 

APPENDIX B 

Page 3 
-84-

APPENDIXC 

COMPUTER PROGRAM FOR CRASHWORTHINESS ANAL YSJS 

Computer Program Summary 

Data defining the curve for an estimated crash pulse is entered into the computer, 

and the program is run. The acceleration curve is generated from the data, and the area 

under the curve is integrated, yielding a curve for velocity. The area under the velocity 

curve is integrated yielding a curve for distance. This is accomplished by dividing the 

acceleration curve into 100 equal time increments. The change· in velocity and distance 

for each increment is calculated using an average acceleration and average velocity for 

that increment. 

Additional documentation of the program is included below. Refer to the following 

lines in the program listing: 

Line 56: DV = (y + Yold) *CONST * DT 

DV (ft/sec) = velocity change for a given increment 

Y, Y01d (G's) =The acceleration in G's at the end (Y) and 

at the beginning (Y old) of each increment 

CONST (constant) = 16.1 = 32.2/2, where 32.2 is the gravitational 

constant, to translate G's to feet per second2• Division by 

2 results in a value for an average G (Y & Y01d) for the 

increment. 

DT (sec) = The time increment, equal to the total time of the 

crash pulse divided by 100. 

Line 57: V(I} = V(I - 1) + DV 

V(I-1) (ft/sec) = velocity at the start of the increment 

V(I) (ft/sec) = velocity at the end of the increment 

Line 58: DIS (I)= ((V(I) + V(I-1)) *.5) *DT 

DIS (I) (ft) = Distance change for a given increment. 

Multiplication by 0.5, results in a value for the average velocity for 

V(I} + V(I-1). 

Line 59: DIS <n = DIS (I) + DIS (1-1} 

DIS (I) (ft) = Cumulative distance of crush, as opposed to the 

incremental distance change calculated on line 58. 

L 

'

-· .. \. 

,· 
,{() 

ir 

f 

~ ! 

r 

' L. 

-85- APPENDIX C 

--.,-------:-.::-----------···------------ ·-·--·------ ~ORTMAN IV V02.2•1 TUE 28•JUN•83 1~:51:19 PAG~ 001. 

,LP:=DL1:(1,77]HUMAN 

_ 0 011.1.------ ... _ . . .. P RO.GR.4ld- !:ill!tEAc....__ .. ________ -------

<.: 

C CREATED 8~ MONTY MONTGUM~MY. OF NTS6 fE-6U 

C JuLY, 198:l . 

···--···-··· c ----------- ------------ ··---------------·-----·-··----.. --------·-" 

l)\.) 0 2 

0003. 

0004 

000~ 

\1006 

0007 

1

)008 

ll\)09. 

0010 

0011 

0012 

0013 

0014 

0015. 

•.) 0 16 

0 !} 1., 

01.118 

L)019. 

C THIS PROGRA~ READS ACCELERATION DATA AND fARGET 

C VALUES fOH VELOCitY AND DIStANCE fROM A USER 

C CREAT~D FILE. TH~ PNOGRAM I~TEGRATES 1HE ACCELERATION . C AND. THE THE. VELOCITY .... :rO....G~:.1:.0ISTAt.lC!!: .. C THE INTEGRATiONS ARE PLUltEO ON THE d04HD 1 S OI IT~L 

C .i:JLOTTI::N TO ALLOW THF: USER TO St:E If HIS ACCt::l .. t:RATlON 

C EStiMATES ARE APPROPRIATE. 

c. ·-·------ ... _.,_-- - ... ___ ---------------------------·-·------·------ c THE ~UANO'S COMPUTER IS A DIGITAL EOUIPME~T CORPORATION 

C POP•ll/40 RUNNl~G RSX•ll/M SOFTWARE. 

C THIS PRUG~A~ IS WRITTEN IN ANSI•66 FORTMAN. c' -.... ··--- ----------·------------ ---------··-------- ---·------ c OI~ENSIU~ D VARIABLES ANO lN!TIALIZAf!UN 

c 

C- . c 

2 

c 

C. 

c 

:la __ c 

c 

c 

32 

3 \ 

c 

c 

c 

c. 

c 

REAL•4 NA{100),fA(100),K(10UJ,fHAC~(l0) 

REA. I..* 4--- . .V. (. 5.0.0 ) .t 01 S-( !>-0-U+rl', S 0-0.) ? X!:tA-C ~!.-- (. 4.0..}-- ... OlME~SIUN VHALK(20),VTIM(20) Dl/'ll~NSION A(500) LUGICAL*l ~UF(80) 

PNO~PT USER fOR DATA ~IL~ AND OPEN IT 

Til-l!:: 1 t'UI-V~AT( I E~TEi-1 INPUT fiLENAMt:: 'S) 

ACCE..PT ... 2 •. 1C..JiUE. ..... -- ----- ....... .. CALL ASSIGN(3,BUf,IC) r0RMAT(Q,80All 

READ .. TA.RGET.. . .VELOCl.TY.._\lA.LUES. At~u. T 1/Yl.t::S.- -· 

~EAD(.),J;l)NVHACK 

0 0 2 ):! 1 = l ,-,~ V H A C K 

Hf.AU.(.3 ,_.33.) V.T! M"U.l#-.W'HA.CK.( I 1. 

R~AD TARGET DISTANCE VALU£S AND 1l~~S 

READ(. 3.12) !HACK------ ------------- fflR,.,AT(lRl 

DtJ .;} 1=1, IliACK 

REAU(J,jj)TnACK(!),XHACKll) 

c u ~· s.r.;; l.b.,..l-.... ..\..... 1--" G-. 12-... -.... ----- . ~---- ---·--

READ ACCEL~RATION VALUES AND TIM~S 

AND CONStRUCT A LihEA~ PIEC~-~ISI:: fUNCTIO~ ARRA¥ 

. ! E •· S L 0 fl t:: S .. A~..U . LN tE.HC.E.£1 S...EO.JL.A.L.L. .. D EF. IN ElL l.N.T t::R~A.L.S-. ___ _ 

0020 ~PARf:O 

0021 READ(J,JJJTA(l),Al . 0U22 ...... - LOO .... J-<J::AO C 3.,.1J.,.L"i0;.9..ll..W: .. 2.~, A....,.2"----:-·-·--------------·---- 0023 33 f0R~AT(2rt0.0) 
APPENDIX C -86-

·--------------- ---------- FU~TNAN IV V02.2•1 TUE 2ij•JUN•8J 12:51:19 _PAGE 002 

,LP:=DL1:(1,77JHUMAN 

0 0 2 4- . - -- -- .. i~ P ART:.n PA 1<-1'_.-t- ----- 0025 IA(Nt:>ART+ll=!'2 0026 ~A(~PARTJ:((A2•AlJ/(T2•TA(hPAMT))) 

0027 b(NPAR£):A~·MA(N~ARTl•T2 

0028------ -AJ..:A-2--------- -----· 0029 GU TO \00 

c 

C INTEGRATION AHEA ••• VELOCIT¥ = VELOCITY + AVG ACCEL~RATIUN * TIM£ 

C- --·- . LliST.At.lCE: =--0 1-'H AN-Cg_-+--AVE:;RAt;E-- VE:~OCIT i-'*-- :f.J-Me;.--------. 

c 

C 1~~ TOTAL Gl~EN lNTEMVAL IS OlVIO~D INTO 100 SUBINTERVALS 

C FOR A PIEC~·wlSE INTEGkAflON • . -·. --C------- ------- ---· ·-··· ----· --··--·- -----

!l030 

0031 

0032-

0033 

(1034 

0(}35 

c T[~ER IS A SUBROUTINE ~HICH METURNS AN ACCELERATION 

C· VALUE FO~ TH~ SPECifiED SUBINTEHVAL, USING TrlE . C PIECE-wiSE LINEAR ARRAY CONSTRUCTED FHO~ THE ACCELERATION 

C--- PO-I NTS----I~-.--:f.t!(!;-.If>i.i<>-U-'t--to~ 1-b-l!;...--- ---·------· ------- ------- C 

":133 CON'[' { N U£ 

TfHN=fA(l) 

T ;,tAX: T A.(.N.P Al< f-+--1.+--------·----·-·--·····--------- ----- DT:(T~AX•TMIN)/100. 

fA(l)~TAll)•.OOOOl 

TACNPARTtl):TA(NPARTtl)t.OOOOl 

() 0 l 0----· -- .. 0 I) 3 7 

T u:.fM I!ll--- - -- -- ---·-·-----· . -- --- ......... . CALL Tl~£R(TO,Y,TA,MA,B,NPART,!FLG) 

lHifLG.NE.Ol GO TO 9000 

. ____ , ___ , _________ _ () i) 3 i:3 

0040 

0041 

0042 

0043 

0044 

004!:i 

Ot)46 

0t)4 7 

0048 

u04~:L .. 0051 

0052 

!J I) 5 3 

9800 

Oil 54. 9900 uo~5 

oo!>o 

iJIJ57 

~) lJ 5 !:s 

0059 

0()60 

0vo1 10 

c - - c 

c 

c 

A(lJ~i 

YUL.U::f 

T<ll=lO 

V(l):VHACK·(t) 

D!S(l >=XHACI\.(1) 

uu 10 l=2.10t.. 

ro=rO+uT 

T(l):TO 

CALL flMEH(10,¥,fA,~A,~,~PAR1,IfL~J 

IF ( 1 L' LG .li.U •. u ). C.U-'l:U. .. 9~00-.- .. TYPE -..;800 ~·!JRMAT( 1 TlMli'lG E:RROk IN fORCING i'UhCTION TIME') ~u l'O 9ooo 

Ci.JN T u~ut.: .. A(l):y 

JV:(Y+YOLOJ*CUNS!*DT 

V( 1 ):V(l-1 )t-Ui/ 

DiS ( L .J: ( (.\1.. ( 1 ).-t.\l. ( l.'!" .. J, • .}..). '-· ~-}. *· U.t -· 01S(1J=UIS(l)+DIS(1•1) 

'iULD=Y 

CONTINUE 

..... ----------------·--·-------

... . .. ··-·· ~·······~·---·-~-·--·--·--·--·----··-··--· ··-···-· .. -" -~~--------~------·--·-

rrlE l~TEGRATt:O VALIJES Ar1D 11--11:: ACCI::LERAflflN F'UNCTiOi~ 

A~£ PLOT11::D HF~I-<E. 

0062 .... ·--. - 0063 

CALL. .. ASS t.c;.t.L{-l._,_!.aL,.:.,.L) ____ ---------·----------------··---------------- CALL CLUSE(3) 

.... ____ , ____ _ 

• 
-87- APPENDIX C 

fORTRAN IV V02.2•1 PAGE 003 ~LP::or.,t: L1,77lHUMAN 

0 1)64---- -- ----CA.L..L.-. ASS-IGN...(.~'"'""""..._,_·+------------------------------·--------~--' 

0065 CA~L PLOTS(O,Oil 

0066 CALL fACTOR(l.O) 0067 CALL NEwPEN(l) . Ou6i:I--------CA.L.L--R£CT.(.0...-.-.0.....rl-l--..--.-~O-r-W--~--··----~----- 0069 CALL PLUT(l.S,.~,-3) 

0070 CALL GR1DCO.,O.,.S,.5,20,20) 0071 CALL SCALE(T,10.,101,1) . 0 0 72.. .CALL.. .SCALE( A ,.1 0...,...;-l-.O.l .. ,_!!L1+--.----------·-·--- U07) CALL ~~~PEN(2) 

0074 CALL AXIS(0.,0.,4HTINE,•4,10.,0.,T(l02),T(103ll 

0075 CALL AXISCO.,O.,bHACC ,6,10.,90.,A(102),A(103)J 

007&___ CALL--SYMtH.li..-C-'!!!....!125, 5.25-,....,..U ... r0-.. 9..U.<>--#-.!"'1.)..----- -----------~ 

0077 CALL L1NECT,A,101,1,1,0) 0078 CALL NE~PEN(3) 

0079 J=101 

0080..------ -- D0-4.0.- I=-1-,-N V-"!AC~---------------------,-------------------------

U081 J=J+l 

00ij2 40 V(J):VHACK<ll OU8J CALL SCALE(V,lO.,J,l) 

u 08 4-------- ... - .. V (.1 0-2-J-=-l/..C...J-+ 1-J.----------·-----·----------------------------- 0085 V{l03}=VCJ+2) 0086 DO 41 J=l,NVHACK 0087 XP=(vTIMlJl•T(102))/TC103) 

0 0 8 8...... Y 1?:...( v 1-i.ACK ( J.).~-~(.1.0 2.}.)../.V-.(..l...Q.J.J..~--------· - -- --·--- -- U089 CALL PLOTCX~·.25,YP,3) 

0U90 CALL PLOT(XP+.25,YP,2J 0091 CAt.L PLUf(XP,tP-.25,J) 

0092. CALL PLO'I.(.tP,¥e.t.25.~<2..l--..... ___ --·-··-·-·· 0093 41 CALL CIRCLCXP+.25,¥P,0.,360.,.25,.25,0.) 0094 CALL AXIS(•.S,O.,bHVEL ,b,10.,9U.~VllU2),V(103)) 

0095 CALL SV~BOL(·.~l25,5.25r.14,1,90.,•ll 

0096 CALL. LHa:cr..il~.l.O.l.,..l,l,.J.J-_ ··- - .... 0097 CALL NEw~EN(4) 

009H J=lOl 

Ou99 DO 42 l=l,IHACK 

g f g ~- 4 2 ~-~~-t-3 y; x -~fAc KT!T---~--~-~---~·-··~ ··--·~---··~~· . -·· ~~----- ... ·---~-----

oto2 CALL SCALf(OIS,lO.,J,l) 

0103 DlS(l02l=OIS(J+1J IJl 0 4.... D 1 S.Ll 03 );;OJ S (J :t :Ll .. Vl05 UU 43 J=l,IHACK 

0106 XP=(THAC~(J)-f(102))/~(10JJ 

0 1 0 7 'i P = ( X HACK ( J l -DIS ( 1 0 2 l ) I 0 IS ( 1 1)3) 

0 1 0 li CALL. t-lLUT ( X..t'-~--• 2.S.,..X.E .. ,..3...).. __________ -----------. -·--·. ·-- .. ---··- ---·· 

0109 CALL PLOTlXP+.25,YP,2J 

0110 CALL PLOT(XP,YP•.25,3) 0111 CALL PLOT(XP,YP+.25,2) 0112 43 . CALL. .. Cll~C.L.(.X.B:t.25.#-¥E..,..O.,..,..J.6.0. ...... -25.,..2!>.,.0 . 0113 CALL AXlS(-l.,O.,bHS ,6,10.,90.,01 ~~~~ CAL~ SVMAOL(•l.Jl25,5.2~,.14,2,YU.,-1J 

0115 CALL Ll~~(T,DIS,101 1,1,2) . 0116 ___ CALL. PLO'L.(.l.A ... ,.~ .. s..,_'!'j J -------·----- 0117 CALL PLOT(0.,0.,999) 

L 
APPENDIX C -88-

FORTHAN I~ V02.2-1 

,LP:=DLt:£1,77JHUMAN 

TU£ 2H-JUN-bl 12:51:19 PAGE 004 

0 1 UL--9 00-0- C A!..l.--CWSg.-(..4..)__ ___ _ 

0119 CALL EXIT 

0120 ENU 
-89- APPENDIX C 

··-- ··--------------- fORTRAN IV STORAGE MAP fOR PROGRAM UNIT HUMfAC 

l,OCAL 

NAME 

Al 

OT 

lC 

J 

TMAX 

T2 

'tOL.D .. -

VARIABLES, .PSECT SDATA, S!ZE = 023042 ( 4881. NQRDS) ·----·····--·--·----·----·------·---··----··-------·------··- --- -----------'--

TYPE UF~S~T NAM~ TYPE OFfSEt NAM~ TYPE OffSET 

R*4 022656 A2 R*4 022666 CONST R*4 022b50 

R*4 022702 OV H*4 022724 I 1*2 022644 

L f 2 _____ Q 2 2.£i..4..Q_ ___ .!E I.£____ .... U 2 0 2 2-1 J..b------- . l~CL- I * 2 ..CU2 b 4 o 

1*2 022730 ~PART 1*2 022654 NVHACK I*2 022642 

R*4 022676 TMlN R*4 022672 TO R*4 022706 

k*4 0226b2 XP R*4 022732 Y R*4 022712 

tH( 4--- 0227 20..-. --- .'tP------·--I:L*4--- .. 0 22-7 ).6.... . ·---·----··-~ 

LUCAL AND CUMMON AHRA~S: 

,~AME------- TYPE.. .•. S£.CT.lU.N-.-OEE'SE~."!~~-~~SI.z.r.;.."!'!.~."!--'"! .. '!!!.. O..t..~<S-I.Olll.~-------' 

A ·R*4 SOATA 016540 003720 ( 1000.) (500) B k*4 SDATA 001440 000620 ( 200.) (100) 

BUF' L*l SDATA Ol2460 000120 ( 40.) (SO) 

t.> IS ......... Rf 4- -···-··- S DA.T-A-.-.-O.Ob-J.l.o__O.O..l~z.o_c.. .. 1.0.0.0.. •. .}.... ( . .50 .0.+-------- ~A W*4 SOATA 000000 000620 ( 200.) (100) 

r H*4 SUATA 012240 003720 ( 1000.) (500) fA R*4. SOATA OU0620 000620 ( 200.) (100) r HACK.. '"'* 4 ... ----- . Sll A.U •. -- u.O.:l2 o.(J.___U.OV.l-2-0.-(-~ -..40-.. -} .... ( 2 0.>--·-------· 

v R*4 SUATA 002400 003720 ( 1000.) (50~) 

VHACK R*4 $DATA 0lb300 000120 ( 40.) (20) vrlM H*4 SDATA 016420 000120 ( 40.) (20) X HACK .. 1H4.... SOA..T.A_ ___ 0.1.616.Q.. ___ Q..O.O.l20..-C-- 4.0 •• ) ... ..(..2.0l------·-· 

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-91- APPENDIX C 

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APPENDIX D e 

CRASHWORTIDNESS PROGRAM INVESTIGATIONS TO DATE 

SIIINT 01 tMSIIIII'!liiiQS ~~ID'I'S 

Ali!J>l.AIIE TOTAL DATE MU AJID P[R$0115 IIIJURI PHASE or TYI'E or 

1982 MODEL OP£AATIOII TUAA!M ACC!O[N'T TYPE 

t-10 I(Qt(T LNIOIIIG TREES, SHRUBS, COll!SIO!t WITH GROIJliO 

II20G Cl1T TREE STOOS 

2·1 BEECH APPROACH AIRPOI!'T COLl!S!Oit WITH GROIJliC 

8£-99 

2·15 PIP£R l.AIIDIHG AIRPORT COll!SIO" WITH OBST~Cl· 

PA·28R-180 

2-27 CESSIIA APPROACH AIRPORT COlliSION WITH GROIJliO 

C·150 

3-8 PIPER CRUISE FARI'I.A/40 COlllSION WITH OSSTACI 

PA·28-180 

3·28 PIPER • 4 T'-UOFF HILlS COLLISION WITH GRO~NC 

PA-28-140 

5·6 PIP£R L'-NO!IIG MOU!lTAlNS COLLISION WITH GROUND 

PA-28R-180 

5·9 BEECH l.AIIOIHG GOLF COURSE COLLISION WITH GROCND 

8£-833 

6-4 CESSIIA IWIEUYERIHG FAAIUHO COlliSIO!t WITH WIRE/ 

C-152-11 GROUND 

6-13 PIPER CRUISE !IAASHLANO COlliSION WITH TREES/ 

PA-28-181 GROUND 

6·17 CESSIIA CRUISE CNI'SITE COlliSION WlTH GROIJliO 

C·152 

7-9 PIPER LNIOIIIG AIRPORT COLLISION WITH GR0\110 

PA-24-250 

1·9 PIPER APPROACH DIRT GAM MIOAIR COUUION/ 

·~) PA-28-160 COLLISION WITH GROIJliC 

7-21 PIPER l.AIIDIHG FARMLAND COLLISION WITH GROUND 

PA-34-ZOOP 

8·1 BEEC~ GO·AROUHD AIRPORT COLLISION WITH GROl'IIC 

BE-23 

8-18 BELl.AIICA CRUISE BEACH 'COLLISION WIT!; GROIJliO 

7ECA 

8-18 PIPER I.AADIIIG AIRPORT COLLISION WITH GROIJliD 

PA-28-235 

8-27 CESSIIA TAKEOFF FARIUHO COLLISIOn WITH TELEPHl 

t-207 POLE 

9·5 PIPER CRUISE RIVER BED COLLI_SION WITH GROUNC 

PA-32·300 

9-20 CESSIIA T'-KEOFF DESERT COLLIS!()!( WITH GROIJliC 

C·I82P 

10-4 BEEOi 2 I.AAOI "G DITCH COLLISIIJI WITH GROUND 

BE-56TC 

10·5 CESSIIA LAHOIHG DITCH COLLIS!ON W!Tf' GROUNC 

C-T210L 

10·18 CESSIIA l.AIIOIHG !YIRSHl.AIID COlLISIOH WITH TREES/ 

t-17Z GROUND 

10-21 PIP£R 4 l.AIIDIIIG PASTURE COLLISION WITH TREtSi 

PA-28-181 GROUND 

10-23 CESSIIA 4 I'AIIEUYERII!G I«JUUITA!N SLOPE COLLIS I ON WITH GROUNC 

C-172 

10-24 PIPER 4 TAKEOff fAR!UHO COLLISION WITH GROUNC 

PA-32-300 

11-8 BEEOi CRUISE fARI'LAHO COLLISION WITli GROUNG 

BE-23 

11-8 CESSIIA APPROACH ROAOS!O[ COLLISION WITH GROu•t 

t-172 

11·18 PIPER GO·AROU!IO AIRPORT COLL!SIO!t WITH GROIJliC 601P 

ll-21 GR~ lAKOIHG AIRPORT COLLISION WITH TREES 

ll-30 

M-5 

C£SSIIA LAJIOING AIRPORT COLL!SII)!j ~!TH TREES ,, C·PZlO