U.S. Department 

of Transportation

Federal Railroad 

Administration

Illinois High-Speed Rail Four-Quadrant 

Gate Reliability Assessment

Safety of Highway Railroad Grade Crossings 

Office of Research

and Development

Washington, D.C. 20590

DOT/FRA/ORD-09/19 Final Report OOOOOOOOOOO

OOO 2009
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1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE

October 2009

3. REPORT TYPE AND DATES COVERED

September 2004 - September 2008

4. TITLE AND SUBTITLE

Illinois High-Speed Rail Four-Quadrant Gate Reliability Assessment

5. FUNDING NUMBERS

RR97/EG081

RR97A1/EG222

6. AUTHOR(S)

Adrian D. Hellman and Tashi Ngamdung

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

U.S. Department of Transportation

Research and Innovative Technology Administration

John A. Volpe National Transportation Systems Center

Cambridge, MA 02142

8.PERFORMING ORGANIZATION 

REPORT NUMBER

DOT-VNTSC-FRA-09-07 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

U.S. Department of Transportation

Federal Railroad Administration

Office of Research and Development

1200 New Jersey Avenue SE.

Washington, DC 20590

10. SPONSORING/MONITORING

AGENCY REPORT NUMBER

DOT/FRA/ORD-09/19

11. SUPPLEMENTARY NOTES

Safety of Highway-Railroad Grade Crossings series

12a. DISTRIBUTION/AVAILABILITY STATEMENT

This document is available to the public through the FRA Web site at http://www.fra.dot.gov

12b. DISTRIBUTION CODE

13. ABSTRACT (Maximum 200 words)

The Federal Railroad Administration (FRA) tasked the John A. Volpe National Transportation Systems Center (Volpe Center) to 

conduct a reliability analysis of the four-quadrant gate/vehicle detection equipment installed on the future high-speed rail (HSR) 

corridor between Chicago and St Louis. A total of 69 highway-rail grade crossings on a 120-mile (193 km) segment of the 280-

mile corridor were equipped with four-quadrant gates and inductive loop vehicle detection technology. This segment, between 

Mazonia and Springfield Illinois, will eventually carry passenger trains at speeds up to 110 mph (177 km/h) at many of the 

highway-rail grade crossings. 

The analysis was based on maintenance records obtained from the Union Pacific Railroad, the owner and operator of the 

highway-rail grade crossings. The results were used to assess the impact of the equipment reliability on the proposed HSR 

timetable. The Volpe Center study showed that the total average delay to the five scheduled daily high-speed passenger 

roundtrips was an estimated 10.5 minutes, or approximately 1 minute per train. Overall, extensive analysis of the trouble ticket 

data showed that the four-quadrant gate and vehicle detection equipment had a minimal direct impact on the frequency and 

duration of grade crossing malfunctions. Moreover, an overwhelming majority of crossing malfunctions equally impacted 

operations of both the entrance and exit gate equipment. 

14. SUBJECT TERMS

Four Quadrant Gate, highway-rail intersection, accident reduction, alternative safety measures, 

safety, reliability assessment, high speed rail, signaling/control technologies, vehicle detection, 

inductive loops

15. NUMBER OF PAGES

47

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(cm2)

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1 square foot (sq ft, ft2) = 0.09 square meter (m

2

) 1 square meter (m2) = 1.2 square yards (sq yd, 

yd2)

1 square yard (sq yd, yd2) = 0.8 square meter (m2) 1 square kilometer (km2) = 0.4 square mile (sq mi, mi2)

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1 ounce (oz) = 28 grams (gm) 1 gram (gm) = 0.036 ounce (oz)

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1 short ton = 2,000 

pounds (lb)

= 0.9 tonne (t) 1 tonne (t) =

=

1,000 kilograms (kg)

1.1 short tons

VOLUME (APPROXIMATE) VOLUME (APPROXIMATE)

1 teaspoon (tsp) = 5 milliliters (ml) 1 milliliter (ml) = 0.03 fluid ounce (fl oz)

1 tablespoon (tbsp) = 15 milliliters (ml) 1 liter (l) = 2.1 pints (pt)

1 fluid ounce (fl oz) = 30 milliliters (ml) 1 liter (l) = 1.06 quarts (qt)

1 cup (c) = 0.24 liter (l) 1 liter (l) = 0.26 gallon (gal)

1 pint (pt) = 0.47 liter (l)

1 quart (qt) = 0.96 liter (l)

1 gallon (gal) = 3.8 liters (l)

1 cubic foot (cu ft, ft3) = 0.03 cubic meter (m3) 1 cubic meter (m3) = 36 cubic feet (cu ft, ft3)

1 cubic yard (cu yd, yd3) = 0.76 cubic meter (m3) 1 cubic meter (m3) = 1.3 cubic yards (cu yd, yd3)

TEMPERATURE (EXACT) TEMPERATURE (EXACT)

[(x-32)(5/9)] F = y C [(9/5) y + 32] C = x F

QUICK INCH - CENTIMETER LENGTH CONVERSION

0 1 2 3 4 5

Inches

Centimeters 0 1 2 3 4 5 6 7 8 9 10 11 12 13

QUICK FAHRENHEIT - CELSIUS TEMPERATURE CONVERSION

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For more exact and or other conversion factors, see NIST Miscellaneous Publication 286, Units of Weights and Measures. Price $2.50 

SD Catalog No. C13 10286 Updated 6/17/98
i

Acknowledgements

The authors wish to thank Leith Al-Nazer and James Smailes (retired), Federal Railroad 

Administration, Office of Railroad Development, for their insight, guidance and direction in 

developing this report. We would also like to thank Stan Milewski and Brian Vercruysse of the 

Illinois Commerce Commission, Rail Safety Section, for providing invaluable technical support 

and data analysis assistance. Special thanks to William Breeden, Director Signal Engineering

(retired), Union Pacific Railroad, who graciously satisfied all of our data requests. We would

also like to express our appreciation to Rick Campbell of Rio Grande Pacific Corporation and 

Matthew Ablett of Railroad Controls Limited for insightful technical discussions about the Exit 

Gate Management System.

Anya A. Carroll, Principal Investigator, Highway-Rail Grade Crossing Safety Research, the 

Volpe National Transportation Center, provided overall direction of the technical information 

and the report preparation, and also provided invaluable guidance and leadership.
ii

Acronyms

AADT average annual daily traffic

DI Delay Index

EGM Electronic Gate Monitor

EGMS Exit Gate Management System

FHWA Federal Highway Administration

FRA Federal Railroad Administration

HSR High-Speed Rail

IDOT Illinois Department of Transportation

km/h kilometers per hour

LRT light rail transit 

m meters

MTTR mean time to repair

MUTCD Manual of Uniform Traffic Control Devices 

MWRRI Midwest Regional Rail Initiative

mph miles per hour

NAJPTC North American Joint Positive Train Control

NEC Northeast Corridor 

PTC Positive Train Control

s seconds

SEHSR Southeast High Speed Rail

UPRR Union Pacific Railroad

USDOT U.S. Department of Transportation

Volpe Center John A. Volpe National Transportation Systems Center
iii

Table of Contents

EXECUTIVE SUMMARY ............................................................................................................ 1

1 Introduction............................................................................................................................. 2

1.1 North American Joint Positive Train Control Program ........................................................ 3

1.2 Purpose............................................................................................................................ 4

1.3 U.S. Four-Quadrant Gate Experiences............................................................................ 4

1.4 Report Layout ................................................................................................................. 5

2 Illinois HSR Corridor.............................................................................................................. 6

2.1 Four-Quadrant Gate Design............................................................................................ 8

2.2 Illinois System Operational Overview.......................................................................... 10

2.3 Vehicle Detection System Operational Sequence......................................................... 10

3 Research Methodology ......................................................................................................... 13

3.1 Evaluation Assumptions ............................................................................................... 13

3.2 Analysis of Entrance and Exit Gate Data ..................................................................... 14

3.3 Theoretical Analysis of Average Time to Fix............................................................... 17

3.4 Theoretical Analysis .................................................................................................... 17

3.5 Calculating Delay.......................................................................................................... 19

4 Results and Discussion ......................................................................................................... 22

5 Conclusions........................................................................................................................... 28

References..................................................................................................................................... 30

Appendix A................................................................................................................................... 32

Appendix B................................................................................................................................... 34

Appendix C................................................................................................................................... 35

Appendix D................................................................................................................................... 36

Appendix E ................................................................................................................................... 38
iv

Tables

Table 1. NAJPTC Program Objectives (Polivka, 2005)................................................................. 3

Table 2. NAJPTC System Functionality (Polivka, 2005)............................................................... 4

Table 3. Typical Representation of the Chicago-St. Louis High-Speed Rail Timetable.............. 14

Table 4. Exit Gate Malfunction Type Definitions........................................................................ 15

Table 5. Malfunction Events Ranked By Event Frequency.......................................................... 23

Table 6. Malfunction Events Ranked by DIMTTR.......................................................................... 26

Table 7. Trouble tickets issued on 11/24 -11/25 of 2004 ............................................................. 27
v

Figures

Figure 1. Midwest High-Speed Rail Network (Transportation Economics and Management 

Systems, Inc., and HNTB Corp., 2004).......................................................................................... 2

Figure 2. Illinois HSR corridor (Tse, 2005).................................................................................... 6

Figure 3. AADT Distribution of the 69 Four-Quadrant Gate Crossings ........................................ 7

Figure 4. Four-quadrant gate (a) single track and (b) double track configurations........................ 9

Figure 5. Four-quadrant gate crossing system timing................................................................... 12

Figure 6. Pareto distribution of malfunctions from Data Set I by reported cause ........................ 15

Figure 7. Exit gate trouble ticket distribution from Data Set I ..................................................... 16

Figure 8. Pareto distribution of malfunctions from Data Set II by reported cause....................... 17

Figure 9. Example of log-normal distribution .............................................................................. 19

Figure 10. Speed profile of a 110 mph train approaching a 15 mph grade crossing .................... 21
1

Executive Summary

The implementation of high-speed rail (HSR) technology, at speeds of 80–110 miles per hour 

(mph), or 129–177 kilometers per hour (km/h), on corridors with pre-existing conventional rail 

service (up to 80 mph (129 km/h) poses several significant challenges, including extensive 

employment of at-grade highway-rail crossings. Frequently, these crossings cannot be closed or 

grade separated, and they are equipped with insufficient warning device technologies to support 

HSR operations. One solution was four-quadrant gates, with inductive loop vehicle detection, 

installed at 69 grade crossings on a 120-mile (193 km) segment of the future 280-mile (451 km) 

HSR corridor between the cities of Chicago and St Louis. This segment, between Mazonia and 

Springfield in the State of Illinois, will carry passenger trains at speeds up to 110 mph (177

km/h) at many of the highway-rail grade crossings. These and other infrastructure improvements 

were completed to reduce the Chicago to St. Louis travel time from 5 1⁄2 to 3 1⁄2 hours and 

increase the number of daily round-trips in each direction from three to five.

The U.S. Department of Transportation’s (USDOT) Research & Innovative Technology 

Administration’s John A. Volpe National Transportation Systems Center (Volpe Center), under 

the direction of the USDOT Federal Railroad Administration’s (FRA) Office of Research and 

Development (R&D), conducted a reliability analysis of the four-quadrant gate/vehicle detection 

equipment based on maintenance records obtained from the Union Pacific Railroad, the owner 

and operator of the grade crossings. The results of this analysis were used to assess the impact of 

the equipment reliability on the proposed HSR timetable.

The Volpe Center study showed that the total average delay to the five scheduled daily highspeed passenger round-trips was an estimated 10.5 minutes or approximately 1 minute per train. 

Overall, extensive analysis of the trouble ticket data showed that the four-quadrant gate and 

vehicle detection equipment had a minimal direct impact on the frequency and duration of grade 

crossing malfunctions.

Analysis of trouble ticket data can be used to identify recurring maintenance issues that may 

require further study. This process may eventually lead to optimization of railroad inspection 

and maintenance procedures, which in the past, railroad inspection and maintenance procedures 

have been modified to minimize the frequency and impact of malfunction events. Fortunately, 

longitudinal analysis of maintenance data will facilitate identification of such long-term trends.

On the basis of this research, railroad and state engineers will be able to review and, if necessary, 

modify maintenance procedures to optimize operation of the four-quadrant gate technology.
2

1. Introduction

The Intermodal Surface Transportation Efficiency Act of 1991 designated five future high-speed 

rail (HSR) corridors (Federal Railroad Administration (FRA), 1997):

 Pacific Northwest

 California

 Chicago Hub Network

 Florida

 Southeast

The Chicago HSR corridor established a ―hub-and-spoke‖ system centered on Chicago, IL, with 

termination points in St. Louis, MO, Detroit, MI, and Milwaukee, WI (FRA, 1997). This effort, 

part of the broader Midwest Regional Rail Initiative (MWRRI), will eventually interconnect nine 

states over a 3,000-mile (4,631 km) system shown in Figure 1. The overall goal of the MWRRI 

is to achieve reliable and frequent HSR service with trains operating at speeds between 90–110 

mph (145–177 km/h). The features of this service will include new train sets, track 

infrastructure improvements, four-quadrant gate warning device technology at high-speed 

highway-rail grade crossings, and railroad signals accommodating the increased speed regimens

(Transportation Economics and Management Systems, Inc. et al., 2004). 

Figure 1. Midwest High-Speed Rail Network (Transportation Economics and Management 

Systems, Inc., and HNTB Corp., 2004)
3

These HSR systems are being implemented on pre-existing rail corridors, with highway-rail 

grade crossings that usually cannot be closed or separated. Typically, these crossings are not 

equipped with the risk mitigation technologies recommended by the United States Department of 

Transportation (USDOT) Federal Railroad Administration (FRA) for rail operations in the 80-

110 mph (145–177 km/h) speed regime (FRA, 1994a). These recommendations, although not 

required, include the installation of sophisticated traffic control/warning devices such as fourquadrant gates equipped with constant warning time and vehicle detection equipment.

1.1 North American Joint Positive Train Control Program

The North American Joint Positive Train Control (NAJPTC) program was created in 1998 under 

the sponsorship of the FRA in a public-private partnership with the Association of American 

Railroads and the Illinois Department of Transportation (IDOT) (FRA, 2008). The ultimate goal 

of this program was a reduction of the Chicago–St. Louis train timetable from 5 1⁄2 to 3 1⁄2 hours. 

In 2000, IDOT selected the 120-mile (193 km) segment between Springfield and Mazonia as a 

test bed for the program, incorporating 110 mph (177 km/h) passenger train service and 

employing radio-based positive train control (PTC) technology. The complete objectives of the 

program are listed in Table 1 and the system functionality is shown in Table 2.

NAJPTC train control technology proved to be very complex and required substantial further 

development before being ready for revenue service operations. In January 2007, the program 

was transferred to a train control test bed at the Transportation Technology Center in Pueblo, 

Colorado. IDOT then elected to install a traditional cab-signal system that will provide the 

safety-critical functionality necessary for safe 110-mph (177 km/h) HSR operations. Once the 

Springfield–Mazonia segment is operational, IDOT expects to upgrade the 30 mile (48 km) 

Joliet–Dwight and the 90 mile (145 km) Springfield–Granite City segments in a similar fashion, 

thereby further reducing the Chicago-St. Louis trip time further (FRA, 2008; Midwest High 

Speed Rail Association, n.d.).

Table 1. NAJPTC Program Objectives (Polivka, 2005)

Objective Description

Safety

Demonstrate PTC safety functionality

 Prevent train-to-train collisions

 Enforce speed restrictions

 Protect roadway workers operating under specific authorities

Interoperability

Develop interoperability standards

 Nonproprietary design

 Railroads own the design (including source code)

Cost Produce cost-effective design with maximum use of commercial-off-the-shelf

components

Mixed mode 

operation

Develop revenue-ready system for high speed passenger trains intermixed 

with freight trains
4

Table 2. NAJPTC System Functionality (Polivka, 2005)

1.2 Purpose

Although installed on a limited basis, grade crossings equipped with four-quadrant gates and 

inductive loop vehicle detection have proven to be an excellent solution in situations where grade 

separation or closure are precluded. The typical application for this crossing treatment, 

especially on HSR corridors, involves about one-half dozen crossings separated by several miles 

of right-of-way.

The NAJPTC system, with 69 four-quadrant gate crossings in a span of 120 miles (193 km), is 

the first large-scale deployment of this treatment type. FRA tasked the USDOT Research & 

Innovative Technology Administration’s John A. Volpe National Transportation Systems Center 

(Volpe Center), to evaluate the reliability of the grade crossing equipment and the potential

impact, if any, on the proposed HSR timetable.

1.3 U.S. Four-Quadrant Gate Experiences 

Although four-quadrant gate technology has been extremely successful as a grade crossing safety 

treatment, HSR experience in the United States has so far been limited to the Northeast Corridor 

(NEC) in Connecticut and the Southeast High Speed Rail (SEHSR) corridor in North Carolina. 

The benefits of the use of this treatment at crossings on these corridors, which demonstrate the 

operational range of four-quadrant gate technology, have been well documented (FRA, 2007; 

FRA, 2001). In addition, the Los Angeles County Metropolitan Transit Authority has 

aggressively deployed four-quadrant gate technology through its light rail transit (LRT) system. 

 Warnings/enforcement of authorities and speeds

 Modular design–for tailored or evolutionary deployment

 Locomotive activation of highway crossing warning systems

 Eliminates need to extend crossing track circuits for high-speed operation

 Fail-safe (vital) implementation and moving block

 Potential to reduce delay during overtakes and recovery from 

 disruptions

 Potential to increase capacity without adding track

 Potential to alleviate need for wayside signals

 Enables high-speed (passenger) train operation

 Open, nonproprietary design–for interoperability & lower recurring cost

 Remote control of switches from locomotive

 Boundary protection

 Handling of equipped and unequipped trains on same track

 Detection, reporting, and protection against rogues & emergencies

 Remote monitoring of train locations and movements

 Potential for paperless bulletins and authorities
5

Through June 2008, a total of 24 crossings have been installed on the Los Angeles Blue and 

Gold LRT lines (A. Zohbi, personal communication, June 2, 2008).

The original NEC HSR improvement strategy was to either close or separate all remaining public 

grade crossings on the corridor (FRA, 1994b). However, neither solution was feasible at eight 

grade crossings in Connecticut for two particular reasons: environmental implications of grade 

separation and the potential disruption to local communities resulting from crossing closure. 

This situation precipitated the deployment of four-quadrant gate technology currently in revenue 

service. In this configuration, an inductive loop vehicle detection platform is vitally integrated 

with the track circuit based cab signaling system. This system is activated by conventional track 

circuits and secures the crossing to prevent motor vehicles from entering during a train event. 

The grade crossing signaling and control system is interconnected with the wayside and in-cab 

signaling systems of Amtrak, the NEC HSR service provider. Any compromise in the integrity 

of the grade crossing equipment is communicated to the locomotive engineer by means of the 

cab signaling system and results in a speed restriction of as low as 15 mph. A motor vehicle 

occupying the crossing, even temporarily, will produce a speed restriction in the vicinity of the 

crossing and cause the exit gates to ascend (FRA, 2001). 

The ―Sealed Corridor‖ initiative is a three-phase analysis of the SEHSR corridor between 

Charlotte and Raleigh, NC. This corridor consists of 216 grade crossings, 44 of which are 

private. The crossing treatments include median barriers, long gate arms, four-quadrant gates, 

and closing of redundant crossings. Other elements of the initiative include traffic separation 

studies to consolidate crossings, video enforcement, video monitoring, data collection, studies of 

driver behavior and the demographics of violators, innovative warning devices, and use of 

improved signs at private crossings. 

The Phase I Sealed Corridor Report to Congress (FRA, 2001) examined 100 at-grade crossings, 

of which 52 were either improved or closed, including 13 treated with four-quadrant gates. 

Unlike the Amtrak system in Connecticut, the North Carolina four-quadrant gate warning 

devices do not employ vehicle detection. The exit gate operation is timed, with an exit gate 

delay in the range of 4–10 seconds (s), to allow motor vehicles to clear the crossing before train 

arrival (Norfolk Southern Corporation and North Carolina Department of Transportation, 2000). 

Through 2007, 49 four-quadrant gate crossings have been installed on the SEHSR, though 

without vehicle detection functionality. 

1.4 Report Layout

Section 2 of this report provides an overview of the Illinois HSR corridor and a technical 

explanation of the four-quadrant gate and vehicle detection systems. Section 3 presents a 

description of the research methodology and an analysis of the reliability data and Section 4 

presents the results of the data analysis and a subsequent discussion.
6

2 Illinois HSR Corridor 

Figure 2 shows the HSR corridor between Chicago and St. Louis. The corridor is owned and 

operated by the Union Pacific Railroad (UPRR), and contains a mix of freight, intercity 

conventional passenger rail, and commuter rail service. The majority of the line is single track 

and at the time the HSR program was initiated, Amtrak operated three daily round-trip passenger 

trains. In 2006, the frequency was increased to five daily round-trip trains. 

The initial goal for the HSR service was eight round trips per day between Chicago and St. 

Louis, with one-way end-to-end travel time of approximately 3 1⁄2–4 hours. However, lower than 

expected funding precluded any further infrastructure improvements between Chicago and 

Dwight, Illinois. Furthermore, fewer high-speed train sets than originally anticipated are being 

procured. As a result, the level of service is now projected at three round-trips per day, with a 

one-way trip time of 4-4 1⁄2 hours. 

The yellow highlighted portion in Figure 2, between Springfield and Mazonia, has undergone 

extensive track rehabilitation, including construction of 12 miles (19 km) of double track and 22 

miles (35 km) of freight sidings, and now satisfies FRA Class 6 track regulations for 110 mph

(177 km/h) train service. 

Figure 2. Illinois HSR Corridor (Tse, 2005)
7

During the initial environmental impact assessment process, 322 public and private crossings 

were identified on the corridor of which 11 have since been closed, leaving 311 remaining. In 

the draft environmental impact statement (DEIS), 68 vehicle and 17 pedestrian crossings were 

proposed for closure. However, opposition from many impacted communities limited the 

number of closures proposed in the final environmental impact statement (FEIS) to 10 vehicle 

and 14 pedestrian crossings. As a result, 174 grade crossings were scheduled to be equipped 

with upgraded warning devices. This consisted of 118 crossings with four-quadrant gates and 

vehicle detection as required by Illinois Commerce Commission regulations for train speeds in 

excess of 79 mph (127 km/h), 51 dual-gate crossings, 4 pedestrian crossings with bells and 

flashers, and one locked gate at a private crossing . Ultimately, the total number of fourquadrant gate crossings was reduced to the 69 grade crossings between Springfield and Mazonia, 

including 49 that support HSR operations highlighted in red in Appendix A (Federal Highway 

Administration (FHWA), FRA, and IDOT, 2003). 

Of the 69 four-quadrant gate crossings, 62 were classified as rural and seven were classified as 

urban. As depicted in Figure 3, average annual daily traffic (AADT) at more than two-thirds of 

the crossings is less than 1,000. 1 This type of low-motor vehicle traffic environment lends itself 

particularly well to the implementation of four-quadrant gate crossing operations at speeds 

between 90 and 110 mph (145–177 km/h). 

0

5

10

15

20

25

30

35

40

1-10 10-100 100-1000 1000-10000

Number of Crossings

Average Annual Daily Traffic Count

Figure 3. AADT Distribution of the 69 Four-Quadrant Gate Crossings

 

1

FRA Office of Safety Analysis database (safetydata.fra.dot.gov)
8

2.1 Four-Quadrant Gate Design

Of the 69 four-quadrant systems installed, 12 were manufactured by Union Switch and Signal

and 57 by Western Cullen Hayes. The grade crossing equipment is continually monitored for 

faults by a solid-state controller. These faults include: crashing of entrance gate arms resulting 

from a sudden power loss, pumping of gate arms, crashing of counterweights if a gate arm 

becomes detached, and overloading of motors caused by a stuck gate arm.

The four-quadrant gate crossing system is comprised of the exit gate management system 

(EGMS), the vehicle detection subsystem, and the gates. The EGMS, manufactured by Railroad 

Controls Limited, is a microprocessor-based controller that works in tandem with the vehicle 

detection system to resolve motor vehicle presence within the grade crossing and supply the 

appropriate gate response. During a train event at the crossing, the EGMS prevents the exit gates 

from lowering until motor vehicle traffic is no longer detected in the crossing (Railroad Controls 

Limited, 2004). If the EGMS detects a compromise in the health of the vehicle detection 

equipment, it instructs the exit gates to ascend.

The four-quadrant gate equipment was designed for compliance with the Manual of Uniform 

Traffic Control Devices (MUTCD) (MUTCD Chapter 8D, 2003). Each gate arm is fully 

reflectorized on both sides with red and white stripes and equipped with three red flashing lights. 

At grade crossings with two-way highway traffic, back-to-back flashing light signals are 

installed on each side of the tracks in all four quadrants. On multilane, one-way streets and 

divided highways, flashing lights are installed on both sides of the road at the entrance to the 

crossing. When the gates are closed, each gate is required to extend across the entrance and exit 

gate lanes of road traffic. 

The vehicle detection subsystem was designed in accordance with Part 3.1.15 of the American 

Railway Engineering and Maintenance-of-Way Association Communications and Signaling 

Manual, Recommended Functional/Operating Guidelines for Control of Automatic HighwayRail Grade Crossing Warning Systems (Milewski, 2005). Each inductive loop consists of a 

prefabricated shared conduit with a single-turn check loop that runs the entire perimeter of the 

three-turn primary loop. The detector amplifier periodically shorts the check loop, resulting in a 

change in inductance, thereby simulating detection of a motor vehicle. If the inductance change 

is not equal to a predefined reference value, the detector displays a message indicating failure of 

the loop. Under this scenario, either the EGMS will direct the exit gates to ascend or the 

crossing will revert to timed operation mode (Reno A and E, undated).

The vehicle detection technology consists of inductive loops embedded within the roadway, 

connected to a solid state vehicle detection unit on the wayside. At single track locations, four 

loops are installed in each approach and exit highway quadrant inside the grade crossing gates. 

For double-track grade crossing applications, an extra pair of loops is installed between the 

tracks. These configurations are illustrated in Figure 4. As described previously, this technology 

has been successfully implemented on Amtrak’s NEC HSR corridor in Connecticut. However, 

the Illinois configuration is not integrated with the train control system.
9

Gate D

Gate A

Gate B

Gate C

Chicago

St. Louis

Northbound Approach

Circuit: 4750 ft

Southbound Approach

Circuit: 4750 ft

S

N

D1

A1 C1

B1

Gate D

Gate A

Gate B

Gate C

Chicago

St. Louis

Northbound Approach

Circuit: 4750 ft

Southbound Approach

Circuit: 4750 ft

S

N

D1

A1

B2

A2 C1

B1

a) Single track configuration

b) Double track configuration

Figure 4. Four-quadrant Gate (a) Single Track and (b) Double Track Configurations
10

2.2 Illinois System Operational Overview

The EGMS operates in two modes with respect to exit gate operation; ―dynamic‖ and ―timed.‖ 

In dynamic mode, which is the primary operational state, exit gate function is dependent on the 

presence and detection of vehicles within the grade crossing. If no vehicles are detected, the 

entrance and exit gates descend simultaneously. Timed mode is the EGMS backup operational 

state. If failure occurs in the EGMS hardware or the vehicle detection subsystem, exit gate 

descent is delayed until the entrance gates have reached the horizontal position. This operational 

mode provides an exit means for vehicles within the crossing when the warning system is 

activated.

The system is designed for fail-safe operation, meaning that the equipment will fail in the most 

restrictive operational state, so as to minimize the increase in risk. Thus, in either dynamic or 

timed operational mode, a loss of system power will result in the entrance gates descending and 

the exit gates ascending. Like the previous description of timed mode, this condition provides a 

path for vehicles within the crossing to exit if power fails. Because the entrance gates remain 

lowered, the railroad civil speed limit at the crossing is reduced to 15 mph (24 km/h).

The basis for the high-speed capability of the four-quadrant gate crossings is the advanced 

activation function in which an approaching PTC-equipped train interrogates the health status of 

the grade crossing using a radio-based communication link. This function is an overlay to the 

underlying conventional track circuit crossing activation circuitry. However, advanced 

activation provides vital support to high-speed operations at the four-quadrant gate crossings in 

two key respects; 1) a constant warning time for train time to arrival and 2) a safe distance for

responding to speed restrictions if the crossing health status is compromised.

Each PTC-equipped locomotive contains an onboard computer with a database of equipped 

crossings, including location, track circuit configuration, conventional approach speeds, and 

warning times. As the locomotive approaches a grade crossing, the locomotive computer 

initiates an advanced activation session with the PTC equipment at the grade crossing. Once the 

advanced activation session is established, the locomotive computer transmits the estimated train 

arrival time to the crossing based on its predicted speed, current locomotive control settings, and 

train and track characteristics. The grade crossing equipment processes the information and 

transmits a response to the locomotive that includes the operational status of the advanced 

activation function and the total time the crossing has been activated (ARINC and CANAC, 

2000). If the crossing equipment is either inoperative or the equipment status cannot be

established, the PTC system will generate a speed restriction equal to the track circuit 

configuration of the crossing, typically 79 mph (127 km/h) (Weber, G., personal communication, 

May 29, 2007).

2

2.3 Vehicle Detection System Operational Sequence

The four-quadrant gate crossings are designed for a 30-second minimum warning time for 

passenger and freight trains operating at 79 mph (127 km/h) and 60 mph (97 km/h), respectively.

 

2 Although the PTC technology is being replaced by a conventional cab-signal system, IDOT anticipates that the 

advanced activation functionality will be integrated within the cab-signal system.
11

When a grade crossing is activated, the gate warning lights flash for 5 seconds. In dynamic 

mode operation, if no motor vehicles are detected and the crossing equipment is operating 

normally, both the entrance and exit gates will descend in tandem. All four gates will arrive at 

the horizontal position within 10 seconds of beginning descent and remain there for a minimum 

of 15 seconds before train arrival. This sequence is depicted in Figure 5. During this time, if a 

vehicle is detected within the crossing, the exit gates will cease lowering and begin to ascend. 

Once the detection system verifies the crossing is unoccupied, the exit gates will resume 

descending. When all of the gates reach the horizontal position and the grade crossing island 

circuit is activated by a train, the vehicle detection system is inhibited. This prevents the train 

from being incorrectly detected as a highway vehicle, which would result in the inadvertent 

raising of the exit gates by the EGMS. Once the rear end of the train clears the island circuit, the 

gates begin to ascend and return to the vertical position within 12 seconds. 

Any malfunction of the EGMS, crossing gates, or the vehicle detection system, will result in the 

four-quadrant gate system automatically defaulting to timed mode operation. In this scenario, 

the exit gates do not initiate descent until the entrance gates are in the horizontal position, 

thereby allowing motor vehicles to clear the crossing. Additionally, all the gates are required to 

be in the horizontal position a minimum of 5 seconds before the arrival of a train at the crossing.

Under certain conditions, speed restrictions are issued to the locomotive as it approaches a fourquadrant gate grade crossing. The first case involves either a non-PTC-equipped locomotive or 

faulty advanced activation functionality at a crossing. In response, the PTC system will revert to 

the underlying track circuit signaling system and the corresponding maximum track speeds. On 

the IDOT HSR corridor, these speeds are typically 79 mph (127 km/h) and 60 mph (97 km/h) for 

passenger and freight operations, respectively. The second scenario is a consequence of the 

crossing equipment being activated more than 2 minutes. If the activation time falls between 2 

and 5 minutes, the existing track circuit speed limit is enforced. In situations involving the 

equipment being activated greater than 5 minutes, a locomotive speed restriction of 15 mph (24 

km/h) is generated.

When a crossing alarm is activated, a trouble ticket is automatically issued and a maintainer is 

dispatched to the crossing. Once the issue is resolved, the maintainer updates and closes out the 

trouble ticket. These records are stored electronically by the UPRR at its central office in Omaha, 

Nebraska. A sample trouble ticket is shown in Appendix B. 
12 CROSSING

TOTAL APPROACH TIME

TOTAL 

WARNING TIME

EQUIPMENT 

RESPONSE

ADVANCED 

PREEMPTION

30 SEC MINIMUM

ALL LIGHTS FLASH

Equipment Response Time

Advanced Preemption Time = 0

Entrance Gate 

Delay 3 Sec. 

Minimum 

Before Gates 

Start to Descend

(IL = 5 Sec.)

Entrance 

Gate Descent

Entrance Gate 

Horizontal 

15 Sec. Min. 

Before Train Enter 

Crossing

Clearance 

Time

(IL = 0)

Buffer Time

(IL = 0)

Exit Gate 

Horizontal

FOUR QUADRANT GATE

Exit Gate 

Delay

EG CT

Exit Gate 

Descent

Start Adv.

Activation

Session

Figure 5. Four-quadrant Gate Crossing System Timing
13

3 Research Methodology

The evaluation process consisted of 1) identifying and characterizing the malfunction types, 2) 

calculating the probability of occurrence and mean time to repair (MTTR) for each malfunction 

type, and 3) estimating the resulting cumulative delay on the proposed HSR timetable.

In April 2005, FRA sent a formal request to UPRR requesting trouble ticket reports for fourquadrant gate vehicle detection technology installed on the Illinois HSR corridor (see Appendix 

C). In May 2005, the UPRR forwarded trouble tickets pertaining to the exit gates, EGMS, and 

the vehicle traffic detection loops for the period from May 9, 2003, and May 3, 2005, (Breeden, 

personal communication, May 13, 2005). In November 2005, the Volpe Center made a second 

request to UPRR for trouble ticket reports relevant to both entrance and exit gate maintenance 

calls. UPRR satisfied this request in February 2006 by providing trouble ticket reports from 

January 2004 through December 2005 (Breeden, personal communication, February 23, 2006). 

These two sets were evaluated by the Volpe Center for trends in malfunction occurrences and 

maintenance downtimes that may impact the future HSR timetable. The second set was 

employed as part of a ―before and after‖ case of the original dual-gate technology on the HSR 

corridor with the four-quadrant gate and vehicle detection systems. Both datasets were used to 

characterize the impact from grade crossing equipment malfunction on the future HSR timetable 

from the types and frequencies of grade crossing equipment malfunctions.

3.1 Evaluation Assumptions

 A constant train velocity of 110 mph (177 km/h) was assumed for the entire corridor. 

 The anticipated number of daily round-trip HSR trains ranges from 6 to 16, depending on the 

available level of funding support for the service.

 The high-speed alternative, the most ambitious approach, has a one-way trip travel time of 

3.5 hours and a 110 mph (177 km/h) maximum train velocity on most of the corridor with 

125 mph (202 km/h) on an 18-mile (29 km) stretch between Lincoln and Springfield, Illinois. 

The preferred alternative has a one-way trip travel time of 4 to 4.5 hours, subject to the extent 

of the infrastructure upgrades. The maximum train velocity under this option is 79 mph (127 

km/h) between Chicago and Dwight and 110 mph (177 km/h) between Dwight and St. Louis. 

The values employed in this analysis, 10 round-trip trains per day and a one-way travel time of 3 

hours and 50 minutes, fall between these two estimates. The high-speed timetable shown in 

Table 3 reflects these assumptions. 
14

Table 3. Typical Representation of the Chicago-St. Louis High-Speed Rail Timetable

3.2 Analysis of Entrance and Exit Gate Data

Data Set I refers to the 93 trouble ticket records for the time period from May 9, 2003, to 

2005. This data set, collected over 726 days, reflects 14 different malfunction types, as 

by the Pareto distribution in 

Figure 6. Analysis of the data showed that four malfunction types contributed to 75 percent of 

the total number of trouble tickets, and the remaining 10 types were responsible for the other 25

percent. 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Gate Mechanical Failure

No Cause Found

Electronics Failure

Gate Hung Up In 

High Wind Bracket

All Was Working

As Intended

Replaced/RepairedGate Arm or Lights

Broken/Damaged

Equipment

Electronics Adjust

Damage By Vehicle

Not Dispatched

Open/Short Circuit

Other

Rehung Gate Arm

Track Circuit Occupied

Malfunction Types

Percent of Total

Mile Southbound: Read Down Northbound: Read Up

0 6:45a 8:15a 3:20a 5:15p 7:15p Chicago 8:25a 10:25a 12:20a 7:00p 9:00p

12 Summit

37 Joliet

74 Dwight

92 Pontiac

124 Normal

156 Lincoln

185 Springfield

224 Carlinville

257 Alton

284 10:35a 12:05p 7:10p 9:05p 11:05p St. Louis 4:35a 6:35a 8:30a 3:10p 5:10p
15

Figure 6. Pareto Distribution of Malfunctions from Data Set I by Reported Cause

The 14 malfunction types were reclassified into the nine categories related to grade crossing 

equipment reliability shown in Table 4. As shown in the Figure 7 pie chart, four malfunction 

types, totaling 28 percent of the trouble tickets—EGMS, loop detector, loop sensor, and exit gate 

activation—were specific to exit gate equipment. Exit gate activation issues, mostly arising from 

oversensitive loop sensors and detectors, accounted for 22 percent of the trouble ticket reports. 

This condition was typically resolved by decreasing detector sensitivity, but maintaining it above 

the motor vehicle detection threshold.

Table 4. Exit Gate Malfunction Type Definitions

Category Definition

Electronic gate 

monitor (EGM) Malfunctions in this group require the EGM to be reset.

Exit gate activation

This is potentially related to the loop detection system sensitivity being set 

too high, usually in conjunction with some form of external electrical 

noise. In the event of this type of malfunction, a loop may indicate vehicle 

detection when no vehicle is present.

Exit gate management 

system

A failure of the EGMS hardware or firmware is resolved by either 

resetting or replacing the EGMS controller board.

Gate mechanical

This type of malfunction results from dirty gate cams not making full up 

or down contact, thereby causing entrance or exit gates to not report 

horizontal or vertical position properly. Replacing or repairing the 

mechanical parts that control gate movement usually resolves this issue.

Loop detector

The loop detector is installed inside the EGMS rack and monitors the 

status of the inductive loops. A failure in the loop detector is indicated by 

an EGMS alarm. This is resolved by either resetting or replacing the loop 

detector controller board.

Loop sensor

If the self-check function detects an inductive loop component failure, a 

loop detector alarm is activated and the exit gate operation defaults to 

timed mode.

Nonspecific Although malfunction causes were observed, they could not be assigned to 

a specific category type. 

Wind

Usually indicative of gates hung up on the high wind brackets or gates 

pumping up and down from high wind. Normally, repositioning the exit 

gates and adjusting the gate contacts resolve this issue.

Wiring

This is manifested by a loose or broken wire in the crossing/vehicle 

detection electronics or the electromechanical equipment controlling gate 

movement.
16

Electronic Gate Monitor, 14, 15%

Non-Specific, 8, 9%

Loop Sensor, 2, 2%

Loop Detector, 2, 2%

Exit Gate Activation, 20, 22%

EGMS, 2, 2%

Gate Mechanical, 22, 23%

Wind, 22, 24%

Wiring, 1, 1%

Figure 7. Exit Gate Trouble Ticket Distribution from Data Set I

Data Set II entrance and exit gate malfunction data were used to analyze the impact of the fourquadrant gate/vehicle detection system on the HSR corridor timetable. The data collection 

period spanned 677 days between February 2004 and December 2005. In total, 889 unique 

trouble tickets were tabulated, equating to an average of 1.31 malfunctions per day. Altogether, 

37 different malfunction types were identified as being specific to the grade crossing equipment. 

Analysis of the data showed that seven malfunction types, as depicted by the Pareto distribution 

in 

Figure 8, contributed to 80 percent of the total number of trouble tickets. The other 30 types 

accounted for the remaining 20 percent. 
17

Figure 8. Pareto Distribution of Malfunctions from Data Set II by Reported Cause.

The weighted probabilities of occurrence and MTTR for each malfunction type were used to 

calculate the impact of the four-quadrant gate/vehicle detection system on the proposed HSR 

timetable. Further analysis of the MTTR data revealed a significant time-based component with 

several orders of magnitude between the highest and lowest values. This is more typical of a 

log-normal distribution rather than a normally distributed, symmetric distribution. For this type 

of application, the geometric mean, which is related to the log-normal distribution, provides a 

more realistic depiction for averaging data. 

3.3 Theoretical Analysis of Average Time to Fix 

For normally distributed, symmetric data, the arithmetic mean would typically be used. 

However, analysis of the MTTR data revealed a significant time-based component with several 

orders of magnitude between the highest and lowest values. Also, the data sets are positively 

skewed and bounded by zero. These characteristics are associated with a log-normal distribution 

rather than a normally distributed, symmetric distribution. 

For this type of application, the geometric mean, which is related to the log-normal distribution, 

provides a more realistic average time to fix estimate. Figure 9 shows an example of a lognormal distribution compared to a normal distribution how the data distributions for the No 

Cause Found type responded to the geometric mean.

3.4 Theoretical Analysis 
18

Consider a set of positive data containing n elements,  a a an

, , ,

1 2 

. The geometric mean of this 

set is defined as the nth root of the product of all the elements. This is expressed as 

n

n

i

ai

1/

1















 = 

n a a an

 

1 2

(1)

This value is less than or equal to the arithmetic mean of the data set and, the two means are 

equal if and only if all data elements are identical.

By using the logarithmic identity,

 

n n a

a e

ln



, the formula may be written as 

n

n

i

ai

1/

1















 = exp















n

i

ai

n

ln 1

(2), where

exp















n

i

ai

n

ln 1

= 

1/ ((ln( ) (ln( ) (ln( )) n a1 a2 ai e  

Since 

ln x  ln y  ln(x  y)

, equation (2) can be rewritten as

exp





























 

n

i

ai

n 1

ln 1

(3), 

and can be reduced to

n

n

i

ai

1/

1

















(4)

This is the exponentiated arithmetic mean of the logarithm transformed values of ai or the 

geometric mean (Mian, 2002). Here ai is the set of repair time values for a single failure type.
19 a) An example of an-adjusted log-normal 

distribution.

b) An example of a log-normal 

distribution on log-normal scale.

c) Unadjusted No Cause Found

 malfunction frequency distribution.

No Cause Found

0

10

20

30

40

0.52.03.55.06.58.09.5

11.012.514.015.517.018.520.021.523.0

Time to Repair (Hours)

Malfunction Frequency

No Cause Found

1

10

100

0.52.03.55.06.58.09.5

11.012.514.015.517.018.520.021.523.0

Time to Repair (Days)

Log (Malfunction Frequency)

d) No Cause Found malfunction frequency distribution 

on log-normal (geometric mean) scale.

Figure 9. Example of Log-Normal Distribution

3.5 Calculating Delay

Let 

MT

= Total number of malfunctions

DT

= Total days

M

= Average number of malfunctions per day

Then
20

T

f

f M

V

P 

T

T

D

M

M 

(5)

Also, let 

Vf = Malfunction code frequency

Pf

= Probability of malfunction code

Then

(6),

the contribution of each malfunction type to 

M = Pf

M

(7), and the average weighted daily 

delay (AWDD) resulting from a malfunction type is 

f NE AWDD  P M 220s , (8)

where the number of affected trains per day is

NE

the total schedule delay from a malfunction, assuming it has occurred is 

NE 110s

(9).

In calculating

NE

, the following assumptions were used:

The geometric MTTR of each malfunction type equals the average time a malfunction will 

affect the HSR timetable,

The proposed Chicago–St. Louis HSR trip time is 3 hr 50 min,

The end-to-end trip time implies an average train speed of 73.2 mph, and

 10 trains will operate daily between Chicago and St. Louis daily (5 round-trips).

Similarly, several assumptions were used in the total schedule delay, NE 110s:

Under worst-case conditions, the maximum allowable train speed at a malfunctioning grade 

crossing is 15 mph (24 km/h),

The train deceleration and acceleration rate is 1 mph/s (0.621 km/s), 

Train length is 500 ft (151 m), including the locomotive, and

A typical crossing is 150 ft (45 m) in length.

Under these assumptions, a train will require 95 seconds to decelerate from 110 mph (177 km/h) 

to 15 mph (24 km/h), while covering a distance of 8,650 ft (2,621 m). At 15 mph (24 km/h), the

train will require 30 seconds to traverse the crossing and clear the island circuit. The process is

then repeated as the train accelerates back to 110 mph (177 km/h), for a total time of 220 seconds

(Meyer 2001). This speed profile is illustrated in Figure 10. Conversely, a train that is not 

required to reduce speed will traverse the entire 17,950 ft (5,440 m) in approximately 110

seconds. The difference between the two times, 110 seconds, is the delay a train will incur due 

to a single malfunctioning crossing.
21

0

20

40

60

80

100

120

0

290053007000820088009200

1140013900159001720018000

Distance (ft)

Speed (mi/hr)

v= 110 mi/hr t=110 s

a = -1 mi/hrs t=95s a = 1 mi/hrs t=95s

t=30s

8650 ft 8650 ft

Figure 10. Speed Profile of a 110 mph Train Approaching a 15 mph Grade Crossing

NE

for each malfunction type was resolved manually by scanning the proposed HSR timetable 

for the interval, equal to the MTTR, in which the maximum number of trains will be present on 

the corridor. Because not all trains on the corridor will be affected by an individual malfunction, 

an approach was developed to estimate the number of trains that will experience a delay. The 

arrival times for each train at the four-quadrant gate crossings, shown in Appendix D, were 

estimated using the proposed 3 hr 50 min schedule.

For example, the MTTR for the ―no cause found‖ malfunction type was calculated as 2 hours 11 

minutes, which was rounded down to 2 hours. The maximum number of trains on the corridor 

for any two hour time period is five. Because the first 64 and last 106 miles (171 km) of the 

corridor are not in high-speed territory, only three of the five trains were found to be affected by 

the ―no cause found‖ malfunction type during the 2-hour time intervals.
22

4 Results and Discussion

In this analysis, 889 unique malfunction tickets were recorded over 677 days, resulting in an 

average of 1.31 malfunctions per day. The probability of each malfunction type, ranging from 

4

11 10

to

2

23.2 10

, was calculated by applying the above delay equations to the data in 

Appendix E. Additionally, the total average daily delay was 10 minutes and 38 seconds, 

equivalent to an average of about one minute per train. Thus, on average, the impact from the 

malfunction codes on the HSR timetable was minimal.

The second and third columns of Table 5 show the malfunction types ranked by event frequency 

and probability of occurrence, unadjusted for MTTR or duration. Two types, no cause found and 

other were typically entered by the grade crossing maintainer when a malfunction was reported 

or an alarm was recorded but could not be duplicated. In many cases, the trouble tickets were 

related to the exit gate equipment, including improper lowering of one or more exit gates, and 

wind issues. Although no cause found and other were not conclusive indicators of delay to the 

HSR timetable, they could not be eliminated as potential predictors of future crossing equipment 

induced delays. 

The geometric averaged weighted daily delay for each malfunction type is shown in the fourth

column of Table 5. These values were calculated from the product of the event probability, the 

number of trains affected per day assuming a 10-train schedule, and the worst-case delay 

experienced by a single train from a malfunction (110 seconds). This calculation yielded a 

probabilistic estimate of the contribution from each malfunction to the average of 1.31

malfunctions/ day. These values, including the total average weighted delay for the entire set of 

malfunction types, are found in the fourth column of Table 5. The sum of the seven malfunction 

types responsible for approximately 80 percent of the trouble tickets contributed over 8 minutes 

to the total 10.5 minutes of average weighted daily delay. Assuming a 10-train daily schedule, 

this equates roughly to an average of one minute per train.

The last column in Table 5 is an estimate of the HSR timetable delay attributed to each 

malfunction event, assuming 100 percent probability of occurrence. These results typify the 

expected delay until a malfunction event has been resolved. Of importance is the marked 

difference from the average weighted delay values. More significantly, these results show that 

the average weighted delay, which is directly related to event probability, may not necessarily be 

the best measure of the impact from a malfunction. A new metric for characterizing the impact, 

delay index (DI), is presented in column 5. This is a measure of the delay incurred on the HSR 

timetable resulting from a particular malfunction type and is analogous to the expression for risk 

in safety-related research. DI is expressed as the product of the event probability, Pf, and the 

average weighted daily delay (eq. 8) resulting from each malfunction type. The formula,

DI AWWD Pf AWDD , (10)

is akin to the expression for risk in safety-related research, where AWDD is the severity term. 

Delay is often used as an alternative metric for risk. However, in this study, the delay index was

employed as a means to measure the delay impact for a grade crossing malfunction, so as to 
23

maintain the distinction with the traditional definition of risk. As shown in fifth column of Table 

5, the average delay term weighs the DI ranking such that the electronics failure and sand, rust, 

or other deposit on rail terms have a stronger impact on timetable delay than as a function of 

event frequency or probability only.

Table 5. Malfunction Events Ranked By Event Frequency

Top 20% of

Malfunction

Events

Event

Frequency

Event 

Probability

(%)

*Average 

Weighted

Daily Delay

(mm:ss)

(DIAWDD) 

No cause found 206 23.17 1:40 38.62

Electronics failure 147 16.54 2:22 39.14

Gate mechanical failure 98 11.02 0:47 8.63

AC power failure 53 5.96 0:42 4.17

Sand, rust, or other 

deposit on rail 48 5.40 1:18 7.02

Gate hung up in high 

wind bracket/cantilever 40 4.50 0:32 2.40

Other 40 4.50 0:19 1.43

Not Dispatched 31 3.49 0:10 0.58

Planned Work 24 2.70 0:19 0.86

Gate Arm Rehung 23 2.59 0:11 0.47

Totals

Highest 20% 710 80 08:20

Remaining 80% 179 20 02:08

For all types 889 100.00 10:38

*This calculation was based on the worst-case condition of 110 s induced delay per train from the time the 

trouble ticket was opened until it was closed. Actual conditions may vary depending on the state of the 

crossing equipment and the discretion of the maintainer.

The following example illustrates how the values in Table 5 were calculated.

In this analysis,

MT

= 889

DT

= 677

So 

M

= 889/677 = 1.31

Consider the electronics failure malfunction code,

where

NE

=6 trains

MTTR = 9 hr 55 min

3 hr 50 min Chicago-St. Louis high-speed rail schedule 

Average train speed of

73.2mi hr

on the corridor 

10 daily trains.
24

In this case, 

Vf =147, yieldingPf =147/889 = 0.1654

The average weighted delay is the product of

f NE P  M 110s

, = (0.1654)(1.31)(110)(6), 

approximately 143s or 2 min 23 sec.

An alternative approach to ranking the impact of malfunctions is presented in 
25

Table 6 with DI now expressed as a function of MTTR. Although not a direct measure of delay 

to the HSR timetable, MTTR is a strong predictor. Here, the delay index is expressed 

as

DI MTTRR Pf MTTR , where MTTR is the severity term. Under this scenario, lower

probability events with large MTTR values may generate a significantly higher DI rank than 

frequently occurring events. These low probability events may also occur concurrently at 

multiple grade crossings, potentially resulting in an amplification of the impact on the HSR 

timetable. 

Consider the case of sand, rust, or other deposit on rail, with a DIMTTR of 896. This malfunction 

type could potentially result in loss of shunt and, under worst-case conditions, yield a significant 

delay. Factors such as the number of impacted crossings and the repair time are highly variable 

and could cause the effect on the HSR timetable to vary significantly. Although the

Pf

for this 

malfunction type (5.40 percent) is in the lower tier of the most frequently occurring malfunction 

types, the MTTR of about 166 hr is the highest of all types. A widespread episode of loss of 

shunt occurred during a two week period 2004 in which virtually all of the sand, rust, or other 

deposit on rail trouble tickets were recorded. The shunt loss encompassed a 25-mile (40 km) 

segment of the corridor, including 30 four-quadrant grade crossings. This resulted in the 

issuance of 30 trouble tickets and a 15 mph (24 km/h) temporary speed restriction at the 

crossings between August 30 and September 13, 2004. For the 30 trouble tickets, the MTTR 

was approximately 272 hours. For the proposed HSR timetable, an estimated 115 trains were 

calculated to be delayed, with the typical train experiencing a delay of almost 55 minutes. These 

values contrast strongly with the MTTR estimate over the 2-year evaluation period of 166 hours

and an average weighted daily delay of 1 minute 18 seconds.
26

Table 6. Malfunction Events Ranked by DIMTTR

Top 10 Malfunctions Based 

on Delay Index Ranking

Event 

Frequency

Event 

Probability

(%)

MTTR

(hh:mm:ss) (DIMTTR)

Sand, rust, or other deposit on rail 48 5.40 165:57:41 896.04

Electronics failure 147 16.54 9:55:26 164.05

No cause found 206 23.17 2:10:59 50.35

Salt/ice in crossing 13 1.46 30:35:33 44.44

AC power failure 53 5.96 6:53:25 41.04

Card/electronic component replace/repair 14 1.57 17:56:55 28.15

Gate mechanical failure 98 11.02 2:10:45 24.01

Broken/damaged equipment 8 0.90 19:55:11 17.55

Open/shorted underground 2 0.22 78:56:10 17.45

Planned work 24 2.70 6:06:28 16.29

Another malfunction episode that impacted railroad operations occurred during a single day. On 

Wednesday, November 24, 2004, Central Illinois was severely impacted by a winter storm. 

Several inches of heavy wet snow fell and changed to ice. The recovery effort was hindered by 

wind speeds over 50 mph (80 km/h) and rapidly falling temperatures. This resulting damage 

included downed power lines, trees, and utility poles. The downed transmission lines resulted in 

loss of power to several electrical substations, impacting large areas of Central Illinois.

3

A total of seven malfunction types, resulting in 31 trouble tickets, were issued at 29 different 

grade crossings during the 24-hour period in which the storm impacted Central Illinois. The 

MTTR for these events was approximately 23 hours. For the proposed HSR timetable, an 

estimated 10 trains would be delayed, with a single train potentially experiencing a delay of 

almost 53 minutes. However, numerous delays occurred during the day of the storm that 

impacted the Amtrak timetable.

Table 7 illustrates the occurrence of malfunction events from November 24–25, 2004. The 

second column shows that two malfunction types, AC power failure and gate mechanical 

contributed to 23 of the 31 trouble tickets. This was equivalent to almost 75 percent of the 

trouble tickets issued. As shown in the third column of 

Table 7, the incidence of these two malfunction types during the snow and ice storm was 

disproportionate to their overall weight in the general population of Data Set II. The most 

plausible explanation for this discrepancy is that these malfunction events were a direct result of 

the snow and ice storm, especially in light of the trouble ticket descriptors supplied by the 

railroad signal maintainers. The descriptors included commercial power failure, snow on the 

 

3

http://www.menard.com/Nov.%2004%20Storm.htm
27

island circuit, ice and snow on gate arms, and high winds preventing the exit gates from 

ascending.

Table 7. Trouble Tickets Issued on 11/24 -11/25 of 2004

Malfunction Event

Event 

Frequency

Event 

Probability

(%)

Data Set II

Event 

Probability

(%)

AC power failure 18 58.1 5.96

Gate mechanical failure 5 16.1 11.02

Other 4 12.9 5.40

Replaced/repaired gate 1 3.2 0.90

Gate hung up in high wind 

bracket/cantilever 1 3.2 4.50

Wet/bad ballast 1 3.2 0.79

No cause found 1 3.2 23.17

Total 31
28

5 Conclusions 

HSR corridors are usually green-field developed dedicated rights-of-way with grade separated 

highway-rail crossings or no crossings at all. However, this optimal state is not always possible, 

especially with incremental HSR deployments. The Illinois HSR corridor, currently under 

development between Chicago and St. Louis, is typical of such a system, where rail corridors are 

upgraded incrementally from the conventional passenger rail speed of 79 mph to 90, 110, 125, 

and eventually 150 mph. Whereas other mechanisms of risk such as inferior signaling systems 

and track can easily be mitigated, highway-rail grade crossings are particularly problematic if 

they cannot be grade separated or closed. One promising treatment, which involves upgrading 

conventional dual-gate crossings to four-quadrant gate systems with inductive loop vehicle 

detection, has been successfully implemented at eight grade crossings on Amtrak’s NEC system 

in Connecticut.

The Illinois implementation, featuring 69 four-quadrant gate/vehicle detection systems over a 

span of 120 miles (193 km), represents the largest installation of this technology to date on a 

HSR system. The purpose of this research was to evaluate the timetable impact, if any, from the 

reliability of the 69 four-quadrant gate/vehicle detection systems installed on the future Illinois 

HSR corridor. Since a HSR timetable was not in existence, the authors constructed a 

representative ―best-guess‖ estimate that is a synthesis of likely one-way trip timetables and 

daily round-trip frequencies published in the public domain.

Equipment reliability was determined using a probabilistic model developed by applying

statistical analysis to identify trends in grade crossing equipment trouble tickets. The 37

malfunction types were sorted by type, frequency (which was used to derive probability), and 

resolution time (which was used to calculate MTTR). The weighted probabilities of occurrence 

and MTTR for each malfunction type were used to calculate the impact of the four-quadrant 

gate/vehicle detection system on the proposed high-speed timetable.

The total average daily delay is 10 minutes and 38 seconds, equivalent to an estimated average of 

one minute per train for a 10-train daily schedule. As such, the reliability of the four-quadrant 

gate/vehicle detection system will incur minimal impact on the HSR timetable. However, some 

interesting insights resulted from this research. First, the majority of trouble tickets were related 

to the maintenance of railroad signaling system components that are interconnected with the 

grade crossing electronics and not an indication of the four-quadrant gate/vehicle detection 

system reliability. Moreover, an overwhelming majority of crossing malfunctions equally 

impacted operations of both the entrance and exit gate equipment. However, the malfunction or 

improper operation of a small subset of components was predicted to result in potentially 

prolonged disruptions to passenger rail operations. These low probability events may occur 

concurrently at multiple grade crossings, potentially resulting in an amplification of the impact 

on the HSR timetable. 

Second, analysis of trouble ticket data can be used to identify recurring maintenance issues that 

may require further study. This may eventually lead to optimization of railroad inspection and 

maintenance procedures. Railroad inspection and maintenance procedures have been modified 

to minimize the frequency and impact of these events. Fortunately, longitudinal analysis of 
29

maintenance data will facilitate identification of such long-term trends. On the basis of this 

research, railroad and state engineers will be able to review and, if necessary, modify 

maintenance procedures to optimize operation of the four-quadrant gate technology.
30

References

ARINC & CANAC. (2000). IDOT PTC Project System Specification Version 3.0. 

www.cours.polymtl.ca/ind6115a/pdf/idot_sss.pdf. 

FHWA, FRA, and IDOT (2003). Final Environmental Impact Statement Chicago - St. Louis 

High-Speed Rail Project. Washington, DC: Federal Railroad Administration, Federal Highway 

Administration, U.S. Department of Transportation, and Illinois Department of Transportation.

FRA (1994a). Rail-Highway Crossing Safety Action Plan Support Proposals. Washington, DC: 

Federal Railroad Administration, U.S. Department of Transportation.

FRA (1994b). The Northeast Corridor Transportation Plan – Report to Congress. Washington 

DC: Federal Railroad Administration, U.S. Department of Transportation. 

FRA (1997). High-Speed Ground Transportation for America. Washington DC: Federal 

Railroad Administration, U.S. Department of Transportation. 

FRA (2001). North Carolina “Sealed Corridor” Phase I U.S. DOT Assessment Report Report to 

Congress. Washington DC: Federal Railroad Administration, U.S. Department of 

Transportation.

FRA (2008). North American Joint PTC (NAJPTC). http://www.fra.dot.gov/us/content/947.

Hellman , A. (2007). Evaluation of the School Street Four-Quadrant Gate/In-Cab Signaling 

Grade Crossing System. Washington DC: Federal Railroad Administration, U.S. Department of 

Transportation. 

Manual on Uniform Traffic Control Devices, Chapter 8D. (2003). Washington, DC.

Meyer, G. (2001). Advanced Grade Crossing Activation Design. Lockheed Martin Presentation.

Mian, M.A. (2002). Project Economics and Decision Analysis, Volume 2: Probabilistic Models. 

PenWell Books, pp. 35-36.

Midwest High Speed Rail Association (n.d.). Five-Year Passenger Train Development Plan for 

Illinois. Chicago, IL.

Milewski, S. (2005). Evaluating 4-Quad Gates on HSR Corridors. 2005 National Highway-Rail 

Grade Crossing Safety Training Conference. Austin, TX.

Norfolk Southern Corporation and North Carolina Department of Transportation (2000). Exit 

Gate-Arm Fail-Safe Down Test. Raleigh, NC.

Polivka, A. (2005). North American Joint Positive Train Control (NAJPTC) Program Update. 

Sixth International Conference on Communications-Based Train Control. Washington, DC.
31

Railroad Controls Limited (2004). Exit Gate Management System User’s Manual Version 2.3 

Software. Benbrook, TX.

Reno A and E (n.d.). PLC Preformed Loop for Railway Applications. Reno, NV. 

Transportation Economics and Management Systems, Inc. and HNTB Corp. (2004). Midwest 

Regional Rail System, Executive Report. Madison WI.

Tse, T. (2005). FRA Initiatives–PTC. National Transportation Safety Board Positive Train 

Control Symposium. Ashburn, VA.

Western Cullen Hayes (2003). Service and Installation Manual for Model 10 Signals Equipped 

with 3597 Gate Mechanisms. Chicago, IL. 
32

Appendix A

Locations of Four-Quadrant Crossings.

(49 that support HSR operations highlighted in red)

Milepost

Mile (km)

Crossing 

Number Crossing Name Location County

Maximum 

Speed

mph (km/h)

64.07 (103.17) 290 517Y Storm Road near Gardner Grundy 79 (127)

64.36 (103.63) 290 518F Washington St. in Gardner Grundy 79 (127)

64.47 (103.81) 290 519M Division St. in Gardner Grundy 79 (127)

64.63 (104.07) 290 521N

Jackson 

/Jefferson St in Gardner Grundy 79 (127)

64.75 (104.26) 290 522V Main St. in Gardner Grundy 79 (127)

65.50 (105.47) 290 525R Maher Rd. near Gardner Grundy 79 (127)

66.91 (107.74) 290 527E Gorman Rd. near Gardner Grundy 79 (127)

69.09 (111.25) 290 531U Stonewall Rd. near Dwight Grundy 79 (127)

70.52 (113.55) 290 533H Scully Rd. near Dwight Grundy 79 (127)

71.14 (114.55) 290 534P Mazon Rd. near Dwight Grundy 79 (127)

71.95 (115.86) 290 535W Livingston Rd. near Dwight Livingston 79 (127)

74.93 (120.66) 290 729C TR 19B near Dwight Livingston 79 (127)

75.93 (122.27) 290 730W TR 220 near Dwight Livingston 79 (127)

76.88 (123.80) 290 732K TR 216B (2400E) near Dwight Livingston 79 (127)

78.96 (127.14) 290 734Y TR 41C (2800N) near Odell Livingston 110 (177)

80.21 (129.16) 290 735F TR 47B (2700N) near Odell Livingston 110 (177)

81.43 (131.12) 290 736M Prairie St. in Odell Livingston 110 (177)

81.52 (131.27) 290 737U Scott St. in Odell Livingston 110 (177)

81.65 (131.48) 290 738B Tremont St. in Odell Livingston 110 (177)

81.72 (131.59) 290 739H Hamilton St. in Odell Livingston 110 (177)

82.69 (133.15) 290 742R TR 69 near Odell Livingston 110 (177)

86.92 (139.96) 290 747A Main St. in Cayuga Livingston 110 (177)

88.90 (143.15) 290 748G

TR 113A/Bunge 

Rd. near Cayuga Livingston 110 (177)

95.85 (154.34) 290 765X TR 159 (1400N) near Chenoa Livingston 110 (177)

98.08 (157.93) 290 770U CR 8 near Chenoa Livingston 110 (177)

99.20 (159.74) 290 771B TR 195A near Chenoa Livingston 110 (177)

100.87 (162.43) 290 774W TR 209 near Chenoa Livingston 110 (177)

101.44 (163.34) 290 775D

TR 1B (Co. Line 

Rd.) near Chenoa McLean 110 (177)

102.04 (164.31) 290 776K Division St. in Chenoa McLean 110 (177)

102.37 (164.84) 290 779F Owsley St. in Chenoa McLean 110 (177)

102.57 (165.16) 290 780A

US 24 (Cemetery 

St.) in Chenoa McLean 110 (177)

103.69 (166.97) 290 781G TR 23A (3000N) near Chenoa McLean 40 (64)

105.93 (170.57) 290 786R TR 35A near Chenoa McLean 40 (64)

108.90 (175.36) 290 790F Orange St near Lexington McLean 40 (64)
33

Milepost

Mile (km)

Crossing 

Number Crossing Name Location County

Maximum 

Speed

mph (km/h)

110.10 (177.29) 290 791M North St. in Lexington McLean 110 (177)

110.27 (177.56) 290 792U Main St. in Lexington McLean 110 (177)

110.36 (177.71) 290 793B Chestnut St. in Lexington McLean 110 (177)

111.65 (179.79) 290 794H TR 83 near Lexington McLean 110 (177)

113.49 (182.75) 290 795P Killian Rd. near Lexington McLean 99 (159)

115.18 (185.47) 290 798K TR 358A near Towanda McLean 99 (159)

118.12 (190.20) 290 801R Madison St. in Towanda McLean 99 (159)

118.25 (190.41) 290 802X Jefferson St. in Towanda McLean 99 (159)

120.03 (193.28) 290 803E

TR 306A / 

Airport Rd near Towanda McLean 99 (159)

127.19 (204.81) 290 949X Miller St. in Bloomington McLean 110 (177)

128.09 (206.26) 290 950S Six Points Rd.

near 

Bloomington McLean 110 (177)

133.70 (215.29) 290 955B TR 443

near 

Bloomington McLean 79 (127)

136.35 (219.56) 290 957P Funks Grove Rd. near McLean McLean 79 (127)

139.12 (224.02) 290 960X TR 533 near McLean McLean 79 (127)

140.91 (226.90) 290 962L Railroad Ave. in McLean McLean 110 (177)

141.16 (227.31) 290 964A US 136 in McLean McLean 110 (177)

143.72 (231.43) 290 967V TR 38 near Atlanta McLean 110 (177)

145.75 (234.70) 290 971K Elm St. in Atlanta Logan 110 (177)

145.81 (234.79) 290 972S Vine St. in Atlanta Logan 110 (177)

145.85 (234.86) 290 973Y Race St. in Atlanta Logan 110 (177)

147.60 (237.68) 290 975M

Lazy Row 

Rd./TR 51 near Atlanta Logan 110 (177)

149.75 (241.14) 290 977B Main St. in Lawndale Logan 110 (177)

150.15 (241.78) 290 978H Lincoln St. in Lawndale Logan 110 (177)

152.18 (245.05) 290 980J TR 222 near Lincoln Logan 110 (177)

153.46 (247.11) 290 982X TR 93 near Lincoln Logan 110 (177)

159.40 (256.68) 294 260E

TR 128 / Prison 

Road near Lincoln Logan 110 (177)

161.30 (259.74) 294 261L TR 149A near Broadwell Logan 110 (177)

163.45 (263.20) 294 263A Main St. in Broadwell Logan 110 (177)

167.30 (269.40) 294 267C Ogelsby St. in Elkhart Logan 110 (177)

168.50 (271.33) 294 269R TR 199A near Elkhart Logan 110 (177)

169.80 (273.42) 294 270K TR 50A

near 

Williamsville Logan 110 (177)

172.35 (277.53) 294 272Y TR 5

near 

Williamsville Sangamon 110 (177)

173.00 (278.58) 294 275U Main St. in Williamsville Sangamon 110 (177)

176.70 (284.54) 294 280R TR 33/Wolf Rd. near Sherman Sangamon 110 (177)

177.87 (286.42) 294 281X Andrew Rd. in Sherman Sangamon 110 (177)
34

Appendix B

Sample Trouble Ticket Report

Ticket # : XXXXXXXXX

CallerType : MAXM

Rptr Name : 

Credible? : N

Occur D/T : 5/9/2003 12:30:59

Dispatched : 5/9/2003 15:42:34

Hold4Mon : 5/13/2003 17:17:33

Hold4Parts : 5/9/2003 16:53:40

Temp Fix Date : 

Closed Date : 5/13/2003 17:18:27

MP Prefix : 0

MP : 064.7500

Status : CLOSED

Control Point : 

DOT : 290522V

Subdiv Nbr : 025

Sub Name : JOLIET

Location : MAIN ST

City : GARDNER

Description : HIGH PRIORITY ALARM.../AWK/

Gang Nbr : 8294

Mtnr Name : XXXXXXX

MSM Nbr : 0785

MSM Name : XXXXXXX

Dept. Cd : 1

Equip Cd : 3

FRA Cd : 2

Resolution Cd : 74

Repair Descr : 74 Electronics Failure -- MTR REPORTS THAT EXIT GATES 

WILL NOT

 COME DOWN UNTIL ENTRANCE GATES ARE HORIZONTAL, , ET REPLACED THE A&E 

 LOOP PROCCESSOR..CMS

Agency : 

PD Notify : 

Req Dispatcher : 

Req Date (XH) : 

Rel Dispatcher : 

Rel Date (XH) : 

Req Dispatcher : 

Req Date (XG) : 

Rel Dispatcher : 

Rel Date (XG) : 

XS DispatchReq : 

XS DispatchReL : 

Work Log : 5/9/2003 12:31:53 EENG384

 Changed Status to: PAGED - 8294

 

 5/9/2003 14:31:31 EENG384

 REPAGED MTR SANDAGE../AWK/

 

 5/9/2003 15:42:37 ENGB440

 Changed Status to: DISPATCHED - 8294

 

 5/9/2003 16:53:43 ENGB440

 Changed Status to: HOLD4PARTS - Test Made: 234.257 System 

 operation.8294

 
35

Appendix C

Letter of Request to Union Pacific Railroad
36

Appendix D

Estimated Arrival Times of High-Speed Trains at Four-Quadrant Gate 

Crossings

Read Down Read Up

M.P Train 1 Train 2 Train 3 Train 4 Train 5 Train 6 Train 7 Train 8 Train 9 Train 10

Chicago 6:45 AM 8:15 AM 3:20 PM 5:15 PM 7:15 PM 8:25 AM 10:25 AM 12:20 PM 7:00 PM 9:00 PM

64.07 7:37 AM 9:07 AM 4:12 PM 6:07 PM 8:07 PM 7:32 AM 9:32 AM 11:27 AM 6:07 PM 8:07 PM

64.36 7:37 AM 9:07 AM 4:12 PM 6:07 PM 8:07 PM 7:31 AM 9:31 AM 11:26 AM 6:06 PM 8:06 PM

64.47 7:37 AM 9:07 AM 4:12 PM 6:07 PM 8:07 PM 7:31 AM 9:31 AM 11:26 AM 6:06 PM 8:06 PM

64.63 7:37 AM 9:07 AM 4:12 PM 6:07 PM 8:07 PM 7:31 AM 9:31 AM 11:26 AM 6:06 PM 8:06 PM

64.75 7:37 AM 9:07 AM 4:12 PM 6:07 PM 8:07 PM 7:31 AM 9:31 AM 11:26 AM 6:06 PM 8:06 PM

65.50 7:38 AM 9:08 AM 4:13 PM 6:08 PM 8:08 PM 7:31 AM 9:31 AM 11:26 AM 6:06 PM 8:06 PM

66.91 7:39 AM 9:09 AM 4:14 PM 6:09 PM 8:09 PM 7:29 AM 9:29 AM 11:24 AM 6:04 PM 8:04 PM

69.09 7:41 AM 9:11 AM 4:16 PM 6:11 PM 8:11 PM 7:28 AM 9:28 AM 11:23 AM 6:03 PM 8:03 PM

70.52 7:42 AM 9:12 AM 4:17 PM 6:12 PM 8:12 PM 7:26 AM 9:26 AM 11:21 AM 6:01 PM 8:01 PM

71.14 7:42 AM 9:12 AM 4:17 PM 6:12 PM 8:12 PM 7:26 AM 9:26 AM 11:21 AM 6:01 PM 8:01 PM

71.95 7:43 AM 9:13 AM 4:18 PM 6:13 PM 8:13 PM 7:25 AM 9:25 AM 11:20 AM 6:00 PM 8:00 PM

74.93 7:45 AM 9:15 AM 4:20 PM 6:15 PM 8:15 PM 7:23 AM 9:23 AM 11:18 AM 5:58 PM 7:58 PM

75.93 7:46 AM 9:16 AM 4:21 PM 6:16 PM 8:16 PM 7:22 AM 9:22 AM 11:17 AM 5:57 PM 7:57 PM

76.88 7:47 AM 9:17 AM 4:22 PM 6:17 PM 8:17 PM 7:21 AM 9:21 AM 11:16 AM 5:56 PM 7:56 PM

78.96 7:49 AM 9:19 AM 4:24 PM 6:19 PM 8:19 PM 7:20 AM 9:20 AM 11:15 AM 5:55 PM 7:55 PM

80.21 7:50 AM 9:20 AM 4:25 PM 6:20 PM 8:20 PM 7:19 AM 9:19 AM 11:14 AM 5:54 PM 7:54 PM

81.43 7:51 AM 9:21 AM 4:26 PM 6:21 PM 8:21 PM 7:18 AM 9:18 AM 11:13 AM 5:53 PM 7:53 PM

81.52 7:51 AM 9:21 AM 4:26 PM 6:21 PM 8:21 PM 7:17 AM 9:17 AM 11:12 AM 5:52 PM 7:52 PM

81.65 7:51 AM 9:21 AM 4:26 PM 6:21 PM 8:21 PM 7:17 AM 9:17 AM 11:12 AM 5:52 PM 7:52 PM

81.72 7:51 AM 9:21 AM 4:26 PM 6:21 PM 8:21 PM 7:17 AM 9:17 AM 11:12 AM 5:52 PM 7:52 PM

82.69 7:52 AM 9:22 AM 4:27 PM 6:22 PM 8:22 PM 7:17 AM 9:17 AM 11:12 AM 5:52 PM 7:52 PM

86.92 7:55 AM 9:25 AM 4:30 PM 6:25 PM 8:25 PM 7:13 AM 9:13 AM 11:08 AM 5:48 PM 7:48 PM

88.90 7:57 AM 9:27 AM 4:32 PM 6:27 PM 8:27 PM 7:11 AM 9:11 AM 11:06 AM 5:46 PM 7:46 PM

95.85 8:02 AM 9:32 AM 4:37 PM 6:32 PM 8:32 PM 7:06 AM 9:06 AM 11:01 AM 5:41 PM 7:41 PM

98.08 8:04 AM 9:34 AM 4:39 PM 6:34 PM 8:34 PM 7:04 AM 9:04 AM 10:59 AM 5:39 PM 7:39 PM

99.20 8:05 AM 9:35 AM 4:40 PM 6:35 PM 8:35 PM 7:03 AM 9:03 AM 10:58 AM 5:38 PM 7:38 PM

100.87 8:07 AM 9:37 AM 4:42 PM 6:37 PM 8:37 PM 7:02 AM 9:02 AM 10:57 AM 5:37 PM 7:37 PM

101.44 8:07 AM 9:37 AM 4:42 PM 6:37 PM 8:37 PM 7:01 AM 9:01 AM 10:56 AM 5:36 PM 7:36 PM

102.04 8:07 AM 9:37 AM 4:42 PM 6:37 PM 8:37 PM 7:01 AM 9:01 AM 10:56 AM 5:36 PM 7:36 PM

102.37 8:08 AM 9:38 AM 4:43 PM 6:38 PM 8:38 PM 7:01 AM 9:01 AM 10:56 AM 5:36 PM 7:36 PM

102.57 8:08 AM 9:38 AM 4:43 PM 6:38 PM 8:38 PM 7:00 AM 9:00 AM 10:55 AM 5:35 PM 7:35 PM

103.69 8:09 AM 9:39 AM 4:44 PM 6:39 PM 8:39 PM 6:59 AM 8:59 AM 10:54 AM 5:34 PM 7:34 PM

105.93 8:11 AM 9:41 AM 4:46 PM 6:41 PM 8:41 PM 6:58 AM 8:58 AM 10:53 AM 5:33 PM 7:33 PM

108.90 8:13 AM 9:43 AM 4:48 PM 6:43 PM 8:43 PM 6:55 AM 8:55 AM 10:50 AM 5:30 PM 7:30 PM

110.10 8:14 AM 9:44 AM 4:49 PM 6:44 PM 8:44 PM 6:54 AM 8:54 AM 10:49 AM 5:29 PM 7:29 PM

110.27 8:14 AM 9:44 AM 4:49 PM 6:44 PM 8:44 PM 6:54 AM 8:54 AM 10:49 AM 5:29 PM 7:29 PM

110.36 8:14 AM 9:44 AM 4:49 PM 6:44 PM 8:44 PM 6:54 AM 8:54 AM 10:49 AM 5:29 PM 7:29 PM

111.65 8:15 AM 9:45 AM 4:50 PM 6:45 PM 8:45 PM 6:53 AM 8:53 AM 10:48 AM 5:28 PM 7:28 PM

113.49 8:17 AM 9:47 AM 4:52 PM 6:47 PM 8:47 PM 6:52 AM 8:52 AM 10:47 AM 5:27 PM 7:27 PM

115.18 8:18 AM 9:48 AM 4:53 PM 6:48 PM 8:48 PM 6:50 AM 8:50 AM 10:45 AM 5:25 PM 7:25 PM

118.12 8:21 AM 9:51 AM 4:56 PM 6:51 PM 8:51 PM 6:48 AM 8:48 AM 10:43 AM 5:23 PM 7:23 PM

118.25 8:21 AM 9:51 AM 4:56 PM 6:51 PM 8:51 PM 6:48 AM 8:48 AM 10:43 AM 5:23 PM 7:23 PM

120.03 8:22 AM 9:52 AM 4:57 PM 6:52 PM 8:52 PM 6:46 AM 8:46 AM 10:41 AM 5:21 PM 7:21 PM

127.19 8:28 AM 9:58 AM 5:03 PM 6:58 PM 8:58 PM 6:40 AM 8:40 AM 10:35 AM 5:15 PM 7:15 PM
37

Read Down Read Up

M.P Train 1 Train 2 Train 3 Train 4 Train 5 Train 6 Train 7 Train 8 Train 9 Train 10

128.09 8:29 AM 9:59 AM 5:04 PM 6:59 PM 8:59 PM 6:40 AM 8:40 AM 10:35 AM 5:15 PM 7:15 PM

133.70 8:33 AM 10:03 AM 5:08 PM 7:03 PM 9:03 PM 6:35 AM 8:35 AM 10:30 AM 5:10 PM 7:10 PM

136.35 8:35 AM 10:05 AM 5:10 PM 7:05 PM 9:05 PM 6:33 AM 8:33 AM 10:28 AM 5:08 PM 7:08 PM

139.12 8:38 AM 10:08 AM 5:13 PM 7:08 PM 9:08 PM 6:31 AM 8:31 AM 10:26 AM 5:06 PM 7:06 PM

140.91 8:39 AM 10:09 AM 5:14 PM 7:09 PM 9:09 PM 6:29 AM 8:29 AM 10:24 AM 5:04 PM 7:04 PM

141.16 8:39 AM 10:09 AM 5:14 PM 7:09 PM 9:09 PM 6:29 AM 8:29 AM 10:24 AM 5:04 PM 7:04 PM

143.72 8:41 AM 10:11 AM 5:16 PM 7:11 PM 9:11 PM 6:27 AM 8:27 AM 10:22 AM 5:02 PM 7:02 PM

145.75 8:43 AM 10:13 AM 5:18 PM 7:13 PM 9:13 PM 6:25 AM 8:25 AM 10:20 AM 5:00 PM 7:00 PM

145.81 8:43 AM 10:13 AM 5:18 PM 7:13 PM 9:13 PM 6:25 AM 8:25 AM 10:20 AM 5:00 PM 7:00 PM

145.85 8:43 AM 10:13 AM 5:18 PM 7:13 PM 9:13 PM 6:25 AM 8:25 AM 10:20 AM 5:00 PM 7:00 PM

147.60 8:45 AM 10:15 AM 5:20 PM 7:15 PM 9:15 PM 6:24 AM 8:24 AM 10:19 AM 4:59 PM 6:59 PM

149.75 8:46 AM 10:16 AM 5:21 PM 7:16 PM 9:16 PM 6:22 AM 8:22 AM 10:17 AM 4:57 PM 6:57 PM

150.15 8:47 AM 10:17 AM 5:22 PM 7:17 PM 9:17 PM 6:22 AM 8:22 AM 10:17 AM 4:57 PM 6:57 PM

152.18 8:48 AM 10:18 AM 5:23 PM 7:18 PM 9:18 PM 6:20 AM 8:20 AM 10:15 AM 4:55 PM 6:55 PM

153.46 8:49 AM 10:19 AM 5:24 PM 7:19 PM 9:19 PM 6:19 AM 8:19 AM 10:14 AM 4:54 PM 6:54 PM

159.40 8:54 AM 10:24 AM 5:29 PM 7:24 PM 9:24 PM 6:14 AM 8:14 AM 10:09 AM 4:49 PM 6:49 PM

161.30 8:56 AM 10:26 AM 5:31 PM 7:26 PM 9:26 PM 6:13 AM 8:13 AM 10:08 AM 4:48 PM 6:48 PM

163.45 8:57 AM 10:27 AM 5:32 PM 7:27 PM 9:27 PM 6:11 AM 8:11 AM 10:06 AM 4:46 PM 6:46 PM

167.30 9:01 AM 10:31 AM 5:36 PM 7:31 PM 9:31 PM 6:08 AM 8:08 AM 10:03 AM 4:43 PM 6:43 PM

168.50 9:01 AM 10:31 AM 5:36 PM 7:31 PM 9:31 PM 6:07 AM 8:07 AM 10:02 AM 4:42 PM 6:42 PM

169.80 9:03 AM 10:33 AM 5:38 PM 7:33 PM 9:33 PM 6:06 AM 8:06 AM 10:01 AM 4:41 PM 6:41 PM

172.35 9:05 AM 10:35 AM 5:40 PM 7:35 PM 9:35 PM 6:04 AM 8:04 AM 9:59 AM 4:39 PM 6:39 PM

173.00 9:05 AM 10:35 AM 5:40 PM 7:35 PM 9:35 PM 6:03 AM 8:03 AM 9:58 AM 4:38 PM 6:38 PM

176.70 9:08 AM 10:38 AM 5:43 PM 7:38 PM 9:38 PM 6:00 AM 8:00 AM 9:55 AM 4:35 PM 6:35 PM

177.87 9:09 AM 10:39 AM 5:44 PM 7:39 PM 9:39 PM 5:59 AM 7:59 AM 9:54 AM 4:34 PM 6:34 PM

St. Louis 10:35 AM 12:05 PM 7:10 PM 9:05 PM 11:05 PM 4:35 AM 6:35 AM 8:30 AM 3:10 PM 5:10 PM
38

Appendix E

Breakdown of Trouble Tickets by Malfunction Type

Code Description Total 

Frequency

Probability

(%)

Average Time 

to fix 

(Geometric

(hh:mm:ss)

1 No Cause Found 206 23.17% 2:10:59

74 Electronics Failure 147 16.54% 9:55:26

91 Gate Mechanical Failure 98 11.02% 2:10:45

57 AC Power Failure 53 5.96% 6:53:25

39 Sand, Rust, Or Other Deposit On Rail 48 5.40% 165:57:41

2 Other 40 4.50% 1:44:34

29 Gate Hung Up In High Wind Bracket/Cantilever 40 4.50% 3:34:00

7 Not Dispatched 31 3.49% 0:34:43

3 Planned Work 24 2.70% 6:06:28

92 Rehung Gate Arm 23 2.59% 2:06:31

90 Replace/Rebuild Gate Arm 21 2.36% 2:17:21

72 Open/Short Circuit 19 2.14% 2:49:28

75 Electronics Adjust 15 1.69% 1:29:56

99 Card/Electronic Component Replace/Repair 14 1.57% 17:56:55

27 Salt/Ice in Crossing 13 1.46% 30:35:33

70 Lightning Arrestor 12 1.35% 5:27:37

58 Blown Fuse/Breaker Trip 11 1.24% 1:33:21

37 Track Circuit Occupied 9 1.01% 1:45:30

69 Broken/Damaged Equipment 8 0.90% 1:33:34

28 Replace/Repair Gate Arm Light(S)/Cord 8 0.90% 19:55:11

35 Wet/Bad Ballast 7 0.79% 3:08:50

30 Broken/High Resistance Bond 7 0.79% 17:28:03

31 Broken Track Wire 6 0.67% 2:05:58

62 Snow/Ice 5 0.56% 2:20:14

15 Damage By Vehicle 4 0.45% 18:21:20

34 Insulated Joint Failure 3 0.34% 3:21:27

36 Shorted Track Circuit 3 0.34% 43:54:06

52 Open/Shorted Underground 2 0.22% 2:44:26

40 Battery Failure 2 0.22% 6:07:25

77 B/O Relay 2 0.22% 78:56:10

104 Human Failure/Intervention 1 0.11% 0:20:00

78 Burned Out/Bad Bulb 1 0.11% 1:48:00

16 High Wind Damaged 1 0.11% 1:54:00

109 Commercial Power Interference 1 0.11% 3:33:00

43 Rectifier Failure 1 0.11% 3:44:00

0 Testing 1 0.11% 6:29:00

71 Resistance Unit 1 0.11% 9:06:00

38 Track Circuit Adjustment 1 0.11% 13:00:00