Electronically Controlled Pneumatic Brake Systems, 50820-50853 [07-4297]

Agencies

• Federal Railroad Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 72, Number 170 (Tuesday, September 4, 2007)]
[Proposed Rules]
[Pages 50820-50853]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 07-4297]



[[Page 50819]]

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Part V





Department of Transportation





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Federal Railroad Administration



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49 CFR Parts 229, 232, and 238



Electronically Controlled Pneumatic Brake System; Proposed Rule

Federal Register / Vol. 72, No. 170 / Tuesday, September 4, 2007 / 
Proposed Rules

[[Page 50820]]


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DEPARTMENT OF TRANSPORTATION

Federal Railroad Administration

49 CFR Parts 229, 232, and 238

[Docket No. FRA-2006-26175, Notice No. 1]
RIN 2130-AB84


Electronically Controlled Pneumatic Brake Systems

AGENCY: Federal Railroad Administration (FRA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: FRA proposes revisions to the regulations governing freight 
power brakes and equipment by adding a new subpart addressing 
electronically controlled pneumatic (ECP) brake systems. The proposed 
regulations are designed to provide for and encourage the safe 
implementation and use of ECP brake system technologies. The proposal 
contains specific requirements relating to design, interoperability, 
training, inspection, testing, handling defective equipment, and 
periodic maintenance related to ECP brake systems. The document also 
identifies provisions of the existing regulations and statutes where 
FRA is proposing to provide flexibility to facilitate the introduction 
of this advanced brake system technology.

DATES: (1) Written comments must be received by November 5, 2007. 
Comments received after that date will be considered to the extent 
possible without incurring additional expenses or delays.
    (2) FRA will hold an oral public hearing on a date to be announced 
in a forthcoming notice.

ADDRESSES: Comments: Comments related to Docket No. FRA-2006-26175, may 
be submitted by any of the following methods:
     Web site: Until September 28, 2007, comments should be 
filed at https://dms.dot.gov. After September 28, 2007, comments should 
be filed at the Federal eRulemaking Portal, https://www.regulations.gov. 
At each site, follow the online instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue SE., W12-140, Washington, DC 
20590.
     Hand Delivery: Room W12-140 on the Ground level of the 
West Building, 1200 New Jersey Avenue SE., Washington, DC between 9 
a.m. and 5 p.m. Monday through Friday, except Federal holidays.
    Instructions: All submissions must include the agency name and 
docket number or Regulatory Identification Number (RIN) for this 
rulemaking. Note that all comments received will be posted without 
change to https://dms.dot.gov including any personal information. Please 
see the Privacy Act heading in the SUPPLEMENTARY INFORMATION section of 
this document for Privacy Act information related to any submitted 
comments or materials.
    Docket: For access to the docket to read background documents or 
comments received, go to https://dms.dot.gov until September 28, 2007, 
to https://www.regulations.gov after September 28, 2007, or to Room W12-
140 on the Ground level of the West Building, 1200 New Jersey Avenue 
SE., Washington, DC between 9 a.m. and 5 p.m. Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: James Wilson, Office of Safety 
Assurance and Compliance, Motive Power and Equipment Division, RRS-14, 
Mail Stop 25, Federal Railroad Administration, 1120 Vermont Avenue, 
NW., Washington, DC 20590 (telephone 202-493-6259); or Jason 
Schlosberg, Trial Attorney, Office of Chief Counsel, Mail Stop 10, 
Federal Railroad Administration, 1120 Vermont Avenue, NW., Washington, 
DC 20590 (telephone 202-493-6032).

SUPPLEMENTARY INFORMATION: 

Table of Contents for Supplementary Information

I. Background
II. Conventional Brake Operations
III. ECP Brake Operations
IV. Interoperability
V. Advantages of ECP Brakes Over Conventional Pneumatic Brakes
    A. Simultaneous Brake Application
    B. Continuous Brake Pipe Charging
    C. Graduated Brake Application and Release
    D. Train Management
    E. Improved Performance
VI. Standards, Approval, and Testing
    A. AAR Standards and Approval Process
    B. FMECA
VII. Market Maturity and Implementation
VIII. Related Proceeding
IX. Legal Impediments and Proposed Relief
X. Additional Issues
    A. Part 229
    B. Dynamic Brake Requirements
    C. Single Car Air Brake Test Approval Procedures and Single Car 
Air Brake Tests
    D. Train Handling Information
    E. Piston Travel Limits
    F. Extended Haul Trains
    G. Part 238
XI. Section-by-Section Analysis
XII. Regulatory Impact and Notices
    A. Executive Order 12866 and DOT Regulatory Policies and 
Procedures
    B. Regulatory Flexibility Act and Executive Order 13272
    C. Paperwork Reduction Act
    D. Federalism Implications
    E. Environmental Impact
    F. Unfunded Mandates Reform Act of 1995
    G. Energy Impact
    H. Privacy Act

I. Background

    Since the inception of automatic air brakes by George Westinghouse 
in the 1870s, brake signal propagation has been limited by the nature 
of air and the speed of sound. Other adjustments have sought to 
alleviate this deficiency, but have left the basic system unaltered. As 
early as 1990, the Association of American Railroads (AAR) has 
investigated more advanced braking concepts for freight railroads, 
including ECP brake systems, which promise to radically improve brake 
propagation by using electrical transmissions of the braking signal 
through the train while still using air pressure in the cylinder to 
apply the force of the brake shoe. During the past 15 years, ECP brake 
technology has progressed rapidly and has been field tested and used on 
various railroads' revenue trains.
    FRA has been an active and consistent advocate of ECP brake system 
implementation. In 1997, FRA participated in an AAR initiative to 
develop ECP brake standards and in 1999, FRA funded, through 
Transportation Technology Center, Inc., a Failure Modes, Effects, and 
Criticality Analysis (FMECA) of ECP brake systems based on the AAR 
standards. FRA also took part in programs to develop and enhance 
advanced components for ECP brake systems.
    To assess the benefits and costs of ECP brakes for the U.S. rail 
freight industry, FRA contracted Booz Allen Hamilton (BAH) in 2005 to 
conduct a study. BAH engaged an expert panel consisting of principle 
stakeholders in ECP brake technology conversion to participate in the 
study. The expert panel made various conclusions relating to 
technological standards, safety, and efficiency. In addition, the final 
BAH report provided a comprehensive analysis and comparison of ECP and 
conventional air brake systems. On August 17, 2006, FRA announced in a 
press release its intention to issue a notice of proposed rulemaking to 
revise the federal brake safety standards to encourage railroads to 
invest in and deploy ECP brake technology. In the press release, FRA 
encouraged railroads to submit ECP brake plans before the proposed rule 
changes are completed.

[[Page 50821]]

    In a petition dated November 15, 2006, and filed November 21, 2006, 
two railroads--the BNSF Railway Company (BNSF) and the Norfolk Southern 
Corporation (NS)--jointly requested that FRA waive various sections in 
parts 229 and 232 as it relates to those railroads' operation of ECP 
brake pilot trains. See Docket No. FRA-2006-26435. FRA held a fact-
finding hearing on this matter on January 16, 2007, featuring testimony 
from representatives of the petitioners, air brake manufacturers, and 
labor unions and issued a conditional waiver on March 21, 2007. See id. 
In drafting this proceeding's proposed rules, FRA has considered 
information filed and decisions made in the related, but separate, 
proceeding concerning the petition for waiver filed by BNSF and NS.

II. Conventional Brake Operations

    While the basic operational concept of the automatic air brake 
system, originally conceived by George Westinghouse in the 1870s, 
remains the same, it has seen continuous improvement in practice. An 
air compressor in the locomotive charges a main reservoir to about 140 
pounds per square inch (psi). With controls located in the locomotive, 
the locomotive engineer uses the main reservoir to charge the brake 
pipe--a 1\1/4\ inch diameter pipe--that runs the length of the train 
and is connected between cars with hoses. The brake pipe's compressed 
air--used as the communication medium to signal brake operations and 
the power source for braking action--then charges each car's two-
compartment reservoir to a pressure of 90 psi. Braking occurs through a 
reduction of air pressure in the brake pipe, which signals the valves 
on each car to direct compressed air from the reservoir on each car to 
its respective brake cylinder for an application of brakes. When air 
pressure is supplied to the brake cylinder--which is connected to a 
series of rods and levers that apply and release the brakes--the 
resulting force presses the brake shoes against the wheel, slowing the 
car's speed.
    While brake applications were initially directed by George 
Westinghouse's triple valve, modern applications direct a control 
valve, which directs air from the brake pipe into the air reservoir 
when air pressure is rising in the brake pipe in order to charge the 
auxiliary and emergency reservoir and be ready for a brake application. 
To perform a brake application, the locomotive automatic brake valve 
reduces pressure in the brake pipe by exhausting air, causing the car's 
control valve to direct air from the auxiliary reservoir into the brake 
cylinder. The increase in pressure to the brake cylinder is 
approximately proportional to the drop in brake pipe pressure. A 26 psi 
reduction in brake pipe pressure is equal to a full service brake 
application on a fully charged brake pipe, and should result in a brake 
cylinder pressure adequate to achieve a full service braking effort 
(brake force). While the control valve is directing air into the brake 
cylinder, or holding air in the brake cylinder, it is unable to 
recharge the auxiliary reservoir on each car. The engineer can apply 
the brakes in increments, at few psi at a time, go directly to a full 
service application of 26 psi reduction, or initiate an emergency 
application of the brakes, as explained below.
    Unlike a brake application, the incremental release of brakes on a 
freight train cannot be accomplished. Brakes can only be fully 
released, called a direct release, and the auxiliary reservoirs then 
begin to charge. Brake applications are possible, but are more 
complicated, from undercharged brake pipe and reservoirs. Recharging 
takes more time for a longer train, because the air has to be sent down 
the length of the train's brake pipe--which can be up to a mile and a 
half. In addition, on extremely long trains, the brake pipe pressure on 
the last car may not reach 90 psi due to small leaks throughout the 
brake pipe, and there may be problems getting enough brake pipe 
pressure to fully release the brakes during cold weather.
    Brake pipe pressure is measured by an end-of-train (EOT) device, 
which is electrically and pneumatically connected to the rear of a 
train equipped with conventional pneumatic brakes and sends signals 
(EOT Beacon) via radio indicating the brake pipe pressure to the lead 
locomotive. Current Federal regulations specify the design and 
performance standards for both one-way and two-way EOT devices. See 
Part 232, subpart E. Both EOT device designs comprise of a rear unit 
pneumatically connected to the rear of the train's last car that an EOT 
Beacon to a Head End Unit (HEU)--a brake system control device mounted 
within the locomotive and used to control the ECP brake system by the 
locomotive engineer and containing the fail-safe software for certain 
undesirable conditions. One-way EOT devices can transmit information 
from the rear unit to the HEU. At a minimum, the one-way device must 
transmit the brake pipe pressure to the HEU and display the reading to 
the locomotive engineer. Two-way EOT devices transmit and receive 
information from both the rear end unit and the HEU.
    An emergency brake application can be initiated in several ways. 
The locomotive engineer can initiate the application by moving the 
brake handle to the emergency position, which exhausts air from the 
locomotive end at a faster rate than the service application. Emergency 
brake applications can also be initiated by opening the conductor's 
valve, located in the cab of the locomotive, or by a break-in-two, 
where the train separates between cars and the brake pipe hoses 
separate, exhausting brake pipe pressure. While performing an emergency 
brake application from the locomotive, a locomotive engineer can also 
use a two-way EOT to initiate an emergency brake application at the 
rear of the train. This permits the emergency application to be 
simultaneously initiated from both the front and rear of the trains and 
ensures that the brakes on the cars at the rear of the train apply in 
the event a brake pipe blockage occurs.

III. ECP Brake Operations

    As early as 1990, AAR began investigating a more advanced braking 
concept for freight railroads, the ECP brake system. The ECP brake 
system radically improves the operation of the automatic air brake by 
using electrical transmissions to signal the application and release of 
brakes on each car in a train while still using compressed air to apply 
the force of the brake shoe against the wheel. ECP brakes also greatly 
simplify the brake system by eliminating multiple pneumatic valves used 
by conventional brakes and replacing them with a printed circuit board 
with microprocessor, one electrically activated application valve, and 
one electrically activated release valve, with feedback on brake 
cylinder pressure for control.
    ECP brake technology requires equipping locomotives and cars with 
special valves and equipment that are unique to the operation of ECP 
brakes. While this system still requires a brake pipe to supply 
compressed air from the locomotive to each car's reservoir in a train, 
there are currently two known methods to send the electronic signal for 
ECP brake operations from the locomotive to each car in the train. 
These methods include using a hard wire electrical cable running the 
length of the train or a radio-based technology requiring a transmitter 
and a receiver installed on the cars and locomotives. At this time, it 
appears that the railroad industry has chosen to use a cable-based 
system for ECP brake operation. Therefore, the proposed rules will be

[[Page 50822]]

limited to operations involving cable-based ECP brake systems.
    ECP brake systems still employ the automatic air brake system's 
basic concept where the locomotive supplies compressed air to each 
car's reservoir via the conventional brake pipe. Each car's brake valve 
reacts to a signal to apply the brakes by directing compressed air from 
the reservoir to the brake cylinder or to release the brakes by 
releasing air from the brake cylinder. The similarities between the 
conventional pneumatic and ECP brake systems end here. Instead of 
utilizing reductions and increases of the brake pipe pressure to convey 
application and release signals to each car in the train, ECP brake 
technology uses electronic signals, resulting in an almost 
instantaneous application and release of brakes on each car in the 
entire train. Since the brake pipe pressure no longer serves as the 
communication medium in ECP braked trains, the brake pipe is constantly 
supplied or charged with compressed air from the locomotive regardless 
of whether the brakes are applied or released. In addition, ECP brake 
equipped trains offer graduated release, where a partial brake release 
command provides a partial, proportional brake release.
    The basic ECP brake system is controlled from the HEU and each car 
is equipped with a Car Control Device (CCD), an electronic control 
device that replaces the function of the conventional pneumatic service 
and emergency portions during electronic braking. The CCD acknowledges 
and interprets the electronic signals from the HEU and controls the 
car's service and emergency braking functions and brake releases. The 
CCD also controls reservoir charging and sends a warning signal to the 
locomotive in the event any component fails to appropriately respond to 
a braking command. Each CCD has a unique electronic address located in 
the Car ID Module, which is keyed to a car's reporting mark and number.
    Each car connects to the locomotive via special connectors and 
junction boxes. More specifically, an ECP brake equipped train's train 
line cable--a two-conductor electric cable (8 A-WG and a 
shield)--connects the locomotive and cars and carries train line power 
to operate all CCDs and ECP brake system's end-of-train (ECP-EOT) 
device and communicates network signals via the power voltage. A Power 
Supply Controller (PSC)--mounted within the locomotive and providing 
230 VDC of electricity--interfaces with the train line cable's 
communication network, provides power to all connected CCDs and ECP-EOT 
devices, and controls the train line power supply as commanded by the 
HEU. Under the AAR standards, a single power supply shall be capable of 
supplying power to an ECP brake equipped train consisting of at least 
160 CCDs and an ECP-EOT device.
    Under the existing regulations, the conventional pneumatic brake 
system's EOT device can lose communication for 16 minutes and 30 
seconds before the locomotive engineer is alerted. See 49 CFR 
232.407(g). After the message is displayed, the engineer must restrict 
the speed of the train to 30 mph or stop the train if a defined heavy 
grade is involved. Per the regulations, railroads must calibrate each 
conventional two-way EOT devices every 365 days and would likely incur 
additional maintenance and cost expenses while replacing its batteries. 
Further, a conventional EOT device is heavy and presents a potential 
for personal injury when applied to the rear of the train.
    By contrast, an ECP-EOT device uniquely monitors both brake pipe 
pressure and operating voltages and sends an EOT Beacon every second 
from its rear unit to its HEU on the controlling locomotive. The HEU 
will initiate a full service brake application should brake pipe 
pressure fall below 50 psi or an emergency brake application should a 
communication loss occur for five consecutive seconds or the electrical 
connection break. An ECP-EOT device may not require calibration and its 
battery, only a back-up for the computer, is charged by the train line 
cable and is much lighter in weight than the conventional EOT device 
battery. Physically the last network node in the train, the ECP-EOT 
device also contains an electronic train line cable circuit--a 50 ohm 
resistor in series with 0.47 micro-farad capacitor--and must be 
connected to the network and transmit status messages to the HEU before 
the train line cable can be powered continuously.
    ECP brake systems have a great advantage of real-time monitoring 
the brake system's health. In normal operation, the HEU transmits a 
message/status down the train line cable to each car. If an individual 
car's brakes do not respond properly to the HEU's brake command, or if 
air pressures are not within the specified limits for operation, a 
message indicating the problem and the applicable car number is sent 
back to the HEU, which in turn notifies the locomotive engineer. The 
ECP brake system can identify various faults, including, but not 
limited to: low brake pipe pressure; low reservoir pressure; low train 
line cable voltage; low battery charge; incorrect brake cylinder 
pressure; and offline or cut out CCDs.
    Emergency or full service brake applications--enabled by compressed 
air propagating pneumatic pressure signals through the brake pipe--
automatically occur when the ECP brake system software detects certain 
faults. For instance, if the HEU detects that the percentage of 
operative brakes falls below 85 percent, a full service brake 
application will automatically occur. In addition, the brakes will 
automatically apply when the following occurs: (1) Two CCDs or the ECP-
EOT report a ``Critical Loss'' within 5 seconds; (2) the train line 
cable indicates low voltage with less than 90 percent operative brakes; 
(3) the ECP-EOT reports a low battery charge; (4) the train moves 
during set-up; (5) the train line cable becomes disconnected; or (6) 
the train exceeds 20 mph in Switch Mode. Under the AAR standards, the 
ECP brake system shall also have a pneumatic back-up system on each car 
for an emergency brake application in the event of a vented brake pipe 
or a train separation. These features preserve the fail safe feature of 
conventional pneumatic brake systems.

IV. Interoperability

    Due to control methodology differences, ECP brake systems are not 
functionally compatible with conventional pneumatic air brake systems. 
For instance, while conventional pneumatic air brake systems command a 
brake application by reducing the air pressure in the brake pipe, ECP 
brake systems command a brake application through a digital 
communications link transmitted on the electrical train line cable. 
Further, conventional freight cars are not equipped with an electrical 
train line cable and must depend on the pneumatic brake pipe for the 
brake command.
    Manufacturers have developed application strategies to address 
issues relating to car and locomotive fleet interchangeability. In 
particular, they have proposed three major schemes of ECP brake design: 
stand-alone systems using only ECP brakes; overlay (dual mode) systems 
capable of operating in either conventional or ECP brake mode; and 
emulation systems, also capable of operating in either conventional or 
ECP brake mode.
    Since cars with stand-alone ECP brake systems do not include a 
fully pneumatic brake control valve, they are incompatible with 
conventionally braked cars and must be operated in complete ECP brake 
equipped train sets. Stand-alone ECP brake systems cannot

[[Page 50823]]

intermix in the same train with conventional pneumatic braked cars 
unless those cars are transported as cars with inoperative brakes. 
While the stand-alone ECP brake system is the least expensive 
alternative of the three design types, its incompatibility with 
conventional pneumatic brake systems requires train segregation, 
potentially posing significant operational problems until the entire 
car fleet is converted to ECP brakes.
    Overlay configurations--cars equipped with both ECP CCDs and 
conventional pneumatic control valve portions--allow cars to operate 
with either ECP or conventional pneumatic air brakes. To operate in ECP 
brake mode, compatible ECP equipment must be installed on the 
locomotive as well as on the freight car. While an overlay system's 
dual mode capability provides significant flexibility, railroad 
operators must purchase, install, and maintain equipment to support 
both types of brake systems for as long as dual mode capability is 
required.
    Emulation configurations use a CCD capable of operating in either 
ECP or conventional mode without requiring conventional pneumatic 
controls. One manufacturer has provided an emulation ECP brake valve 
that monitors both the digital communications cable and the brake pipe 
for a brake command. If an electrical signal is present, the ECP brake 
valve operates in ECP brake mode. If the electrical brake command 
signal is not present, then the valve will monitor the changes in the 
brake pipe pressure like a conventional pneumatic control valve and the 
CCD will use a software program to emulate the function and response of 
a conventional pneumatic valve. This mode is called limited emulation 
and is meant to be used for small cuts of cars hauled short distances 
at slow speeds with a non-ECP brake equipped locomotive. An emulation 
ECP brake system can be operated in any train with any mix of emulation 
ECP and conventional brake systems. In a mixed train, the emulation ECP 
brake system will monitor the brake pipe for pressure changes and set 
up brake cylinder pressure like a conventional pneumatic valve. 
Currently, FRA does not propose any rules uniquely regulating trains or 
cars equipped with emulation ECP brake systems. However, FRA seeks 
comments on whether or how it should regulate such systems differently 
than what is proposed herein.
    Manufacturers have also addressed ECP brake compatibility with 
conventional pneumatic brake equipped locomotives, which must be 
equipped with a HEU unit to operate the brakes on ECP brake equipped 
cars. For instance, one manufacturer has developed a portable unit that 
will allow a non-ECP brake equipped locomotive to operate an ECP brake 
equipped train by converting the air pressure changes in the brake pipe 
to digital command signals that are transmitted to the freight cars 
through the electrical train line cable. The locomotive engineer 
operates the brakes with the conventional automatic brake valve in the 
control cab. The brakes, however, will respond instantaneously and 
provide all of the benefits of an ECP brake system.

V. Advantages of ECP Brakes Over Conventional Pneumatic Brakes

    ECP brake technology overcomes many of the physical limitations 
inherent in conventional pneumatic brake technology. Field testing of 
AAR compliant ECP brake systems over the past decade has not revealed 
any indication of a catastrophic event that could be caused by an ECP 
brake system malfunctioning. With a high level of confidence, the ECP 
brake stake holders support the implementation of ECP brake systems on 
the Nation's railroads. FRA concludes that the advantages of ECP brake 
technology will significantly improve the safety and the performance of 
train operations. Examples of such benefits include better train 
handling through simultaneous brake applications, continuous brake pipe 
charging, and graduated brake operation. ECP brake benefits also 
include electronic train management and improved performance.

A. Simultaneous Brake Application

    The conventional pneumatic brake system uses compressed air as the 
source for braking power and as the medium for communicating brake 
application and release commands and communicates brake commands by 
changing brake pipe pressure through the use of the locomotive 
automatic brake control valve. These commands begin at the front of the 
train and propagate to the rear of the train at the speed of the air 
pressure moving from car to car. This slow propagation of the brake 
command contributes to uneven braking, excessive in-train and run-in 
forces, train handling challenges, longer stopping distances, safety 
risks of prematurely depleting air brake reservoirs, and a 
corresponding low brake rate until all cars in the train receive and 
fully respond to the brake command. FRA recognizes that the slow 
application and release of brakes in a train causes excessive in-train 
forces, which have the potential to cause derailments when they occur 
in curves, cross-overs, or when heavier cars are placed at the rear of 
the train. When the brakes on the rear of the train release much more 
slowly than the brakes on the front of the train, the potential for a 
``string-line'' derailment--where the train stretches out until one or 
more wheels are lifted off the inside of a curve--increases.
    The ECP brake system reduces these problems by enabling cars to 
brake simultaneously at the command of an electronic signal. The 
electronic signal's speed ensures an instantaneous, simultaneous, and 
even activation of each car's brake valves, significantly reducing 
braking distances--40 to 60 percent for the longest trains--and 
minimizing the consequences of collisions or derailments by reducing 
the collision speed and slowing the non-derailed portion of the train.

B. Continuous Brake Pipe Charging

    Propagating a brake command signal through the induction or 
reduction of air pressure in the brake pipe represents a significant 
limitation of conventional pneumatic brakes. The same brake pipe air 
used to propagate brake commands also charges reservoirs on each 
freight car. As a result, the brake pipe must be fully charged to 
restore full braking capacity to depleted reservoirs. Partially 
depleted air from the brake pipe, which occurs during the initial stage 
of braking, prohibits repeat applications of brakes until the brake 
pipe can be recharged. A brake pipe can only be recharged once the 
brakes have been fully released. This characteristic of conventional 
pneumatic brakes contributes to the risk of run-away trains caused by 
prematurely depleted brake pipe pressure, particularly on steep grades.
    The ECP brake system reduces this risk by continuously charging the 
brake pipe. Since ECP brakes do not use the brake pipe as a brake 
command medium, the brake pipe is constantly being charged, allowing 
the locomotive engineer to operate the brake system more aggressively. 
With ECP brake systems, it is unnecessary to apply hand brakes on steep 
grades to recharge the brake pipe after the train stops on the grade.

C. Graduated Brake Application and Release

    The conventional pneumatic brake system's inability to operate 
freight trains in graduated release has long hampered train operations 
and has increased fuel consumption. The conventional pneumatic brake 
system

[[Page 50824]]

can only operate in direct release, preventing locomotive engineers 
from reducing the braking effort without completely releasing and 
resetting the brakes. In other words, after a direct release brake 
application with a conventional pneumatic brake system, braking effort 
can be increased but not decreased without fully releasing the brakes. 
In many cases, direct release leads to unnecessary train stops and 
insufficient initial brake applications. ECP brake systems overcome 
this deficiency by operating in graduated release, which enables the 
operator to reduce braking effort to a lower level after making an 
initial brake application without fully releasing the brakes. As a 
result, the operator can accurately adjust the braking level as each 
situation requires, eliminating the stops required to recharge and 
reset the brakes after excessive brake applications and prior to 
negotiating hills and valleys.

D. Train Management

    The use of a train line cable allows real-time self-diagnostic 
functions to be incorporated in the brake system. The initial check of 
brake system conditions on each car and continuous monitoring of each 
car's braking functions provides immediate communication to the 
locomotive engineer of certain brake failures. The continuous 
monitoring of each car's braking functions and real-time diagnostics of 
the train's brake system is a significant advantage to the locomotive 
engineer for the operation of the train and provides justification to 
eliminate the need for some of the required physical inspections of the 
train and supports regulatory change to operate cars with non-
functioning brakes out of the initial terminal. When the ECP brake 
system diagnostics detect a serious problem, including when the brake 
pipe pressure falls below 50 psi, the ECP brake system will 
automatically command a penalty brake application. ECP brake systems 
also eliminate the conventional pneumatic brake system's inability to 
apply all brakes in the train when there is a blockage in a brake pipe, 
which is handled through the use of a two-way EOT telemetry device not 
required by all trains. This failure will not affect brake applications 
in ECP brake systems, because each car is provided a braking command 
through a train line cable, not solely through the reduction of brake 
pipe pressure, which would not be propagated through the consist if the 
brake pipe is blocked. Therefore, ECP brake systems incorporate 
features that make them inherently safer than conventional pneumatic 
brakes. Using sensor-based technology to maintain a continuous feedback 
loop on train conditions for the crew and any centralized monitoring, 
the electrical communication cable network can also serve as a platform 
for the gradual addition of other train performance monitoring and 
management controls, including distributed power locomotive control, 
automatic activation of hand brakes, hot bearing detection, and truck 
oscillation and vibration. These and other train management features 
will increase the reliability and overall safety of train operations.

E. Improved Performance

    Ultimately, ECP brake technology also provides improved 
performance, which will contribute to safer train operations and 
significant cost savings over time. Since ECP brake operated trains can 
operate in graduated release, instead of direct release, of the brakes, 
fuel will not be wasted while dragging trains against a brake 
application. Further, because all of the cars' ECP brakes release 
instantaneously, fuel will not be wasted on initial start-ups and 
power-ups after a brake application.
    Operations utilizing ECP brake systems also promise increased 
average train speeds and decreased trip times. ECP brake systems allow 
the locomotive engineer to modulate the brake applications in 
territories with descending grades, thus increasing overall trip 
average speeds and reaching destinations sooner. While the slow release 
of the rear cars' brakes on conventional pneumatic braked trains cause 
drag, the brakes on ECP brake equipped trains release simultaneously, 
improving start-up and acceleration times. Further, due to its shorter 
stopping distances, trains equipped solely with ECP brake systems may 
potentially permit higher train speeds within existing signal spacing, 
which will increase average system velocity, or permit use of shorter 
``blocks'' between signals, facilitating greater system capacity.
    The instantaneous application and release of ECP brakes will result 
in more uniform braking, thus improving wheel wear and lengthening 
brake shoe life. In a conventional pneumatically braked train, the 
brake pipe gradient and slower response time causes the first third of 
the train's cars to provide the majority of the braking action, thus 
applying additional pressure and heat on those cars' wheels. Since ECP 
brake systems provide instantaneous braking on all cars, such pressure 
will be more uniformly distributed along the train, thus eliminating 
the uneven braking force on the wheels of those leading cars. The ECP 
brake system also self-monitors each car's brake cylinder pressure and 
maintains the prescribed pressure, thus reducing the potential for 
creating shelling and flat spots on wheels.
    Due to minimized wheel defects, and their accompanying vibrations, 
freight cars and brake components will enjoy increased life. Further, 
instantaneous braking will also prevent draft gear assemblies from 
receiving the constant pressure caused by trains equipped with 
conventional pneumatic brake systems and will reduce lading damage by 
eliminating slack action and in-train forces caused by uneven braking. 
ECP brake systems will also reduce the number of brake parts and rubber 
diaphragms required by conventional pneumatic brake systems.

VI. Standards, Approval, and Testing

    During the past 17 years, FRA has monitored the progression of ECP 
brake technology and has observed field testing on various revenue 
trains, both freight and passenger. In 1997, FRA participated in an AAR 
initiative to develop ECP brake standards and in 1999, FRA funded, 
through the Transportation Technology Center, Inc., an FMECA of the ECP 
brake system based on AAR's Standards and Recommended Practices, S-4200 
Series. FRA also participated in programs to develop and enhance 
advanced components for ECP brake systems. After all of these efforts, 
FRA has decided that the AAR S-4200 Series of standards is appropriate 
substantively and legally for adoption by reference in this rule and 
that the AAR Air Brake Systems Committee is an appropriate vehicle to 
rely upon in the implementation of ECP brake technology and this rule.
    FRA acknowledges that ECP brakes are an attractive, viable, and 
enabling technology with the potential to substantially improve the 
operational efficiency of trains and that by complying with AAR 
Standard S-4200, ECP-braked trains offer significant safety and 
efficiency benefits in freight train handling, car maintenance, fuel 
savings, network capacity, self-monitoring, and fail-safe operation. 
FRA proposes that all suppliers obtain AAR approval for ECP brake-
equipped-trains intended for use on U.S. railroads.
    AAR administers the existing industry ECP brake standards through 
its Air Brake Systems Committee--consisting of representatives from the 
major railroads, brake manufacturers, and FRA--which requires 
demonstrated proof of compatibility, safety, and reliability of air 
brake systems to receive AAR approval. FRA is satisfied that the

[[Page 50825]]

existing AAR S-4200 specifications, AAR approval procedures, and 
continuing oversight by the AAR Air Brake Systems Committee will best 
ensure the safety and reliability of ECP brake systems. An ECP brake 
monitoring system complying with AAR Standard S-4200 Series increases 
safety by communicating information on the location and quantity of 
defective equipment and by providing for the safe movement of equipment 
over longer distances and periods of time.

A. AAR Standards and Approval Process

    In order to assure the safety and the interoperability of ECP brake 
system designs, AAR developed the S-4200 Series of standards. The first 
five standards (S-4200, S-4210, S-4220, S-4230, and S-4250)--issued in 
1999 and updated in 2002 and 2004--specify the functional, operational, 
and interface requirements for cable-based ECP brake systems. AAR 
issued two additional standards in January 2007, specifying ECP brake 
equipment approval procedures (S-4240) and interoperability testing 
requirements (S-4260). AAR has not completed specifications for radio-
based ECP brakes, which it considers technically immature and 
unsuitable. The purposes of the standards are to ensure that AAR-
approved electronic brake systems are interoperable between different 
manufacturers and meet high standards of safety and reliability. The 
analysis of the S-4200 Series of standards indicates that the 
performance specifications for the cable-based ECP brake concept are 
complete.
    The AAR Manual of Standards and Recommended Practices (MSRP) 
contains the following standards for cable-based ECP brake systems:
     S-4200, ECP Cable-Based Brake Systems--Performance 
Requirements;
     S-4210, ECP Cable-Based Brake System Cable, Connectors, 
and Junctions Boxes--Performance Specifications;
     S-4220, ECP Cable-Based Brake DC Power Supply--Performance 
Specification;
     S-4230, Intratrain Communication Specification for Cable-
Based Freight Train Control System;
     S-4240, ECP Brake Equipment--Approval Procedure;
     S-4250, Performance Requirements for ITC Controlled Cable-
Based Distributed Power Systems; and
     S-4260, ECP Brake and Wire Distributed Power 
Interoperability Test Procedures.
    The main standard, S-4200, ensures that the functionality and 
performance of freight ECP brake systems are uniform and consistent 
among equipment from different manufacturers, that cars equipped with 
AAR-approved ECP brake systems from different manufacturers are 
interoperable, and that AAR-approved electronic brake systems meet a 
high standard of safety and reliability. This standard defines ECP 
brake system elements, specifies their functionality in different 
implementation schemes--such as stand-alone, overlays, and emulators-- 
and sets the requirements for all system functions. It covers all 
primary functions of ECP brakes, including graduated brake application 
and releases, continuous reservoir charging, adjustment of braking 
level to car load, continuous fault detection, equipment status 
monitoring, and pneumatic backup. It also specifies requirements for 
all modes of train operation and provides an extensive description of 
fault response and recovery functions for all possible faults of the 
system components. The standard also establishes environmental 
requirements for the designed systems, in-service testing, and rigorous 
approval procedures for certification process of new ECP brake 
equipment.
    Other standards in the AAR S-4200 Series (S-4210, S-4220, S-4230, 
S-4250, and S-4260) contain requirements for critical ECP brake system 
components and communication protocols. Standard S-4210 contains the 
performance specifications and qualification test procedures for ECP 
brake system cables, connectors, and end-of-car junction boxes. The 
required testing verifies that the designed components have high 
reliability, will withstand harsh environmental conditions, and will 
have at least an 8-year operating life.
    Standard S-4220 contains performance specifications for the DC 
power supply system through the hard-wired train line cable for ECP 
brake controllers and other electronic freight car components. Since a 
DC power supply conductor will also send communication control commands 
between a locomotive and its attached cars, the standard requires 
reliable separation and absence of interference between the DC power 
supply and the communication circuits.
    Standard S-4230 contains the requirements related to intra-train 
communication systems on freight equipment used in revenue interchange 
service. The standard facilitates interoperability between freight cars 
and locomotives without limiting the proprietary design approaches used 
by individual suppliers. The communication protocol was developed for 
control of ECP brakes and multiple remote units, including distributed 
power locomotives, and for safety reporting of various car and 
locomotive components.
    Standard S-4250 contains the methodology and communication flow 
requirements for controlling the operation of multiple locomotives in a 
freight consist through the intra-train communication network that is 
shared with the ECP brake system. The locomotive control through the 
intra-train communication line is an alternative method of locomotive 
control, which was not available before the introduction of ECP brake 
system technology. The controlled locomotives can either trail a lead 
locomotive or be remotely located (i.e., separated by cars) in a train. 
The standard establishes protocols for different types of locomotive 
controls through the intra-train line cable, depending on the location 
of the consist's multiple locomotives.
    Standard S-4260 contains the test procedures that must be completed 
by ECP brake suppliers to establish interoperability baselines among 
ECP brake and wire distributed power (WDP) systems in compliance with 
the S-4200 standards series. The test procedures validate the 
functional interoperability of ECP brake and WDP systems developed by 
different manufacturers.
    The AAR approval process and the work of the Air Brake Systems 
Committee has been the primary method of ensuring the safety and 
reliability of railroad brake systems and components for decades. FRA 
proposes that meeting all the requirements of the AAR ECP brake 
standards and obtaining AAR approval will be a prerequisite for any new 
ECP brake system to be employed on U.S. railroads. Through its 
participation on the Air Brake Systems Committee, FRA can monitor any 
safety or reliability issues that may develop with ECP brake systems. 
In the event of a serious safety issue with a supplier's ECP brake 
system, FRA can appropriately respond by invoking its authority to 
intervene with additional rulemaking or an emergency order. FRA does 
not expect to use this authority, because the AAR Air Brake Systems 
Committee already has the authority to rescind AAR approval for brake 
systems that do not perform safely or reliably.
    Standard S-4240 contains the acceptance procedure for seeking AAR 
approval of ECP brake equipment. The standard requires a manufacturer 
to apply for approval by submitting certain information under 
Administrative Standard S-060. Following review and

[[Page 50826]]

approval of the initial application data and test plan by the AAR Air 
Brake Systems Committee, a manufacturer maintains the burden of 
establishing compliance with Standards S-4200, S-4210, S-4220, S-4230, 
S-4250, and S-4260 to obtain conditional approval.
    For laboratory testing, an AAR representative will select 150 CCDs 
from a lot of 200 and will select HEUs, train power supplying units 
(TPSs), and ECP-EOTs from lots of four each. The testing will be 
performed on a 150-car test rack configured in accordance with AAR 
specifications. The manufacturer will provide for AAR evaluation of the 
test results, which shall include a requirements traceability and 
compliance matrix for each AAR standard and all necessary test reports, 
and then conduct interoperability laboratory testing between new ECP 
brake equipment and AAR-approved ECP brake equipment in accordance with 
standard S-4260.
    Upon satisfactory completion of the aforementioned laboratory 
tests, AAR will consider conditional approval for field testing of ECP 
brake equipment. If conditional approval is granted, 150 ECP brake CCDs 
shall be selected from a production lot of 200 test-approved CCDs, and 
100 of those selected, plus at least two ECP brake equipped locomotives 
and one ECP-EOT device, must be placed in railroad service for 24 
months. Under conditional approval, at least 1,000 cars must be 
allotted for use.
    Within those 24 months, all in-service tests must be conducted. 
After those 24 months, the Air Brake Systems Committee continues to 
monitor the product for reliability and safety concerns. If a problem 
with any brake component is discovered, the Committee will discuss the 
issue and may either demand further tests or withdraw AAR approval.
    Full AAR approval shall be provided after 4 years if during that 
time a manufacturer furnishes AAR at specified intervals various 
service reports, which must include accurate ECP brake equipment 
malfunction records. FRA agrees with AAR's assessment that 4 years are 
needed to collect a history of reliable data with minimum failures. In 
addition, the manufacturer must provide to AAR a semiannual report 
containing any repair material for the test ECP brake equipment. Under 
the draft standard, AAR reserves the right to withdraw conditional test 
approval if it determines that safety is impaired, reliability 
degrades, or incompatibility of ECP brake operation develops, and may 
require any additional testing or performance evaluations it deems 
necessary. Standard S-4240 also contains specific procedures that must 
be followed when a manufacturer intends to change certain ECP brake 
equipment physical characteristics, software, or electronics.
    FRA supports this effort as a timely measure for AAR to strengthen 
the regulatory package for ECP brake systems. Overall, FRA considers 
AAR approval a valuable step to ensure the reliability and safety of 
ECP brake systems and a minimum requirement for initial application of 
ECP brake systems on the Nation's railroads. However, FRA fully intends 
to monitor the application and safety of ECP and may, at its 
discretion, require additional safety analysis to be performed to 
confirm the safety of ECP brake systems installed and operating in 
revenue service. FRA reserves the right to witness the AAR approval 
testing of the product.

B. FMECA

    AAR Standard S-4200 Series was developed to support the design of a 
safer, more reliable ECP braking system when compared with conventional 
air brakes. Once the standard was created, the railroad industry 
identified the need to perform a safety and reliability assessment of 
an ECP brake system built in accordance with this standard. Since 
actual S-4200 ECP brake systems did not yet exist, the industry decided 
to conduct a FMECA for a hypothetical ECP brake system that satisfied 
all the requirements of the standard. At FRA's insistence, the FMECA on 
AAR Standard S-4200 was performed in 1999 by DEL Engineering with 
participation of AAR, FRA and a number of experts with significant 
experience in the development and application of ECP brake systems.
    The FMECA team began the analysis by identifying all major ECP 
brake system components and their intended functions. The analysis 
examined each component and function and identified associated failure 
modes and effects. The failure modes were analyzed to determine 
severity, frequency of occurrence, and effectiveness of detection. The 
FMECA team created a numeric ranking criterion and determined and 
prioritized the level of risk posed by each failure mode. High risk 
failure modes were identified and appropriate mitigation strategies 
were developed to decrease the risk.
    The FMECA team analyzed the failure modes of all ECP brake 
components, including: CCDs with the battery; HEUs on the head 
locomotive; ECP-EOT devices; train line cables, communication and power 
supplies; power supply controllers; head end line terminators; car ID 
modules; locomotive ID modules; and operative brakes. The analysis 
included different types of ECP brake systems, including stand alone, 
overlay (dual mode), and emulator and all system functional 
requirements and operating modes, including Initialization, Switch, 
Run, and Cut-out. The FMECA failure log contained about 1,500 failure 
modes. For each high-risk failure mode, the FMECA team identified 
action items and offered recommendations on how to mitigate the 
consequences of component failures or system functional failures. The 
team primarily examined single-point failures but also identified and 
evaluated some cases of combined failures that had significant safety 
consequences.
    The FMECA results confirmed that the ECP brake concept offers the 
potential for improved performance, reliability, and safety over that 
of conventional pneumatic brake systems. The FMECA concluded that no 
failure mode of an AAR-compliant ECP brake system exists that can cause 
a catastrophic accident due to single-point failure of the system 
itself. The AAR standards, as written, eliminate or mitigate critical 
outcomes of single-point failure of ECP brake systems.
    The FMECA team encouraged manufacturers to pursue ECP brake 
technology, because the potential safety and efficiency benefits will 
far outweigh any disadvantages. If designed and maintained properly, 
ECP brakes will be substantially safer and more reliable than the 
conventional pneumatic brake system they are intended to replace.
    AAR and the brake manufacturers indicated that they were completely 
satisfied that ECP brake systems are significantly safer than 
conventional pneumatic systems. They accepted the results of the FMECA 
and concluded that no modifications were necessary to the AAR standards 
related to ECP brake systems.

VII. Market Maturity and Implementation

    The U.S. market for ECP brake systems is mature enough to begin 
implementation of ECP brake technology. The equipment manufacturers 
have made a significant investment in the technology and have completed 
the preliminary design work and field testing of ECP brakes. For 
instance, they have provided technical solutions for different ECP 
brake implementation strategies, enabling non-ECP and ECP brake 
equipped cars to run in combined trains and, in some cases, allowing 
ECP-equipped freight cars to run in ECP brake mode using locomotives 
with conventional

[[Page 50827]]

pneumatic brake systems. In addition, they are ready to supply fully 
operational stand-alone ECP brake systems, overlays, and emulators for 
the U.S. market, easing the industry's migration process. A commitment 
by the railroad industry to change over to ECP brakes is necessary to 
inspire additional technological initiatives by the manufacturers.
    ECP brake systems from three U.S. manufacturers--all in different 
stages of AAR approval and testing in revenue service--have been built 
with the intention of complying with the AAR S-4200 Series of 
standards, proven safe through field testing, designed using fail-safe 
principles, and accommodated the industry's need for a different 
implementation scheme. The AAR S-4200 Series standards are intended to 
assure the necessary level of safety, reliability, interoperability, 
and, ultimately, the applicability of this equipment in the U.S. 
market. The equipment of all three suppliers relies on the conventional 
pneumatic emergency brake system as a backup in case of failure of the 
ECP brake control. In most cases, ECP brake systems will support 
enhanced safety even if the electronics fail, because continuous 
recharging of the brake pipe will ensure availability of an emergency 
application. Therefore, the ECP brake system reduces the risk caused by 
depleted air in the case of an emergency. There is no instance of a 
malfunctioning ECP brake system that resulted in a catastrophic or 
critical event.
    To assess the benefits and costs of ECP brakes for the U.S. rail 
freight industry, FRA contracted BAH in 2005 to conduct a study. An ECP 
brake expert panel of principal stakeholders in the conversion of the 
U.S. freight car fleet to ECP brake technology, including suppliers, 
railroads, private car owners, AAR, and FRA was assembled to 
participate in the study. The expert panel supports the conclusion that 
the AAR standards are sufficient for the ECP brake system designer to 
achieve a system safety level adequate for a safety-critical system. In 
particular, an AAR-compliant system, while providing a significant 
increase in safety and efficiency, does not introduce extra risks 
associated with single-point failure of the ECP system itself.
    The final BAH report provided a comprehensive analysis and 
comparison of ECP and conventional air brake systems. BAH acknowledged 
that while trains with ECP brake systems have been run in North 
America, South America, and Australia, U.S. implementation has been 
stalled due to the absence of an acceptable implementation plan for 
conversion and hard data to support a sound economic analysis, limited 
interoperability with traditionally braked trains, and insufficient 
capital investment required for conversion. It concluded that although 
the barriers to implementation are formidable, ECP brake systems are 
economically and technically ripe for adoption and should be 
implemented in phases over the course of 2 to 4 years to collect hard 
data supporting further implementation. BAH posits that implementing 
ECP brakes on 2,800 locomotives and 80,000 cars in the Powder River 
Basin (PRB) would cost the industry approximately $432 million. 
However, according to BAH, the annual $157 million in anticipated 
benefits--resulting from saved fuel, improved wheel and brake shoe 
life, and a reduction in necessary brake inspections--will allow 
railroads to recover those costs in less than three years. To justify 
the investment, the BAH report says, conversion must be focused first 
on the high-mileage, unit-train-type services that would most benefit 
from its use.
    FRA acknowledges that BAH's fuel cost estimates are substantially 
underestimated due to subsequently rising prices and that the benefits 
from improved wheel life require re-evaluation since BAH was privy to 
insufficient hard data. It is notable that BAH did not attempt to 
quantify potential savings relating to capacity increases or emissions 
decreases due to the difficulty in arriving at acceptable values. 
Accordingly, the report's estimated internal rate of return should be 
viewed as conservative.

VIII. Related Proceeding

    In a petition dated November 15, 2006, and filed November 21, 2006, 
BNSF and NS jointly requested that FRA waive various sections in parts 
229 and 232 as it relates to those railroads' operation of ECP brake 
pilot trains. See Docket No. FRA-2006-26435. The FRA Safety Board held 
a fact-finding hearing on this matter on January 16, 2007, featuring 
testimony from representatives of the petitioners, air brake 
manufacturers, and labor unions. On March 21, 2007, the Safety Board 
granted the petitioners' request, in part, subject to various 
conditions designed to ensure that trains subject to the waiver will be 
as safe as trains operated without benefit of the waiver. See Id. FRA 
will closely monitor compliance with the waiver and verify brake system 
and component performance characteristics using unannounced inspections 
of trains subject to the waiver.

IX. Legal Impediments and Proposed Relief

    ECP brake operation provides for continuous electronic monitoring 
of air brake system components condition and brake pipe pressure, 
potentially limiting the need for certain physical brake inspections 
currently required under part 232. Accordingly, FRA proposes modifying, 
relaxing, or removing certain requirements, including intermediate 
terminal inspections (Sec.  232.209), single-car air brake tests (Sec.  
232.305), and the required percent of operable brakes at initial 
terminal departure (Sec.  232.103(d)), as they apply to trains 
operating in ECP brake mode.
    The rail industry's implementation of ECP brakes is frustrated by 
such inapplicable and inefficient statutory and regulatory 
requirements. Without a large-scale proliferation and implementation of 
ECP brake technologies, the industry will not be able to enjoy 
economies of scale and to overcome the industry-wide limits caused by 
interoperability problems. FRA seeks to improve market efficiency by 
providing reliable and suitable standards and procedures that will 
support investments in ECP brake technology.
    The current statutory and regulatory requirements, however--
including those concerning brake inspections and the operation of 
trains with defective equipment--may reduce or eliminate incentives for 
railroads to implement new ECP brake technology and take advantage of 
its operational and safety benefits. For example, 49 U.S.C. 20303 
presents an obstacle to cost-saving, safe, and efficient long hauls 
promised by ECP brakes. To avoid incurring civil penalties, operators 
are required under 49 U.S.C. 20303 to transport rail vehicles with 
defective or insecure equipment ``from the place at which the defect or 
insecurity was first discovered to the nearest available place at which 
the repairs can be made.''
    When the defective equipment is an ECP brake, stopping for a 
physical inspection is not necessary, as it does not increase the safe 
operation of the train. If more than 15 percent of the train's AAR 
approved ECP brakes become inoperable, the train automatically stops. A 
train with 85 percent operative ECP brakes will have 15 percent less 
overall braking capacity than a conventional pneumatic train with 100 
percent operative brakes--an important concern when operating on long 
grades. However, a train with 85 percent operative ECP brakes will 
still

[[Page 50828]]

have shorter stopping distances than a conventional pneumatic braked 
train with 100 percent operative brakes. Considering the technology's 
continuous self-monitoring and constant communication with the 
engineer, it is highly unlikely that a train will ever reach such a 
level of inoperability. Further, FRA believes that an ECP brake 
operated freight train may travel non-stop to its destination, not to 
exceed 3,500 miles, because foundation brake rigging and brake shoes 
will safely operate over this distance and redundant intermediate brake 
inspections for an ECP brake operated train moving that distance do not 
increase ECP brake system safety. As an added benefit, the increased 
mileage allowance would provide for coast-to-coast travel. In the 
related proceeding, Docket No. FRA-2006-26435, FRA's Safety Board 
granted the request of BNSF and NS to allow the non-stop movement of an 
ECP brake operated train to its destination, each not to exceed 3,500 
miles. FRA believes that the proposed rule should codify this 
regulatory relief so that it applies universally.
    Nevertheless, 49 U.S.C. 20303 requires trains with defective 
equipment, including brakes, to travel to the nearest repair location. 
If the nearest available repair location is in a direction other than 
that in which the train is traveling, the train with defective 
equipment must switch the defective car out of the train and add it to 
another train traveling in the direction of the repair location, 
sometimes requiring a ``backhaul.'' ECP brake implementation has been 
complicated by the ECP brakes system's technological incompatibility 
with conventional pneumatic brake systems. To switch a car equipped 
with ECP brakes into a technologically incompatible train operating 
with conventional pneumatic brakes, however, will create additional 
safety hazards for that train.
    The potential risks involved in combining cars with incompatible 
braking systems coupled with the hazards normally associated with 
switching cars in the field, likely outweigh the potential harm of 
keeping the defective car in its existing ECP braked train and 
traveling to a repair location that is further away. In circumstances 
where the defective safety appliance is a non-brake defect, it may be 
safer and more efficient to allow ECP brake equipped trains with non-
brake defective equipment to travel to the nearest forward repair 
station. Moreover, due to the ability of ECP brake systems to 
continuously monitor the brakes on each car in a train and to provide 
specific information to the locomotive engineer regarding the location 
of any car with inoperative brakes and the inherent design of such 
systems to prohibit operation with less than 85 percent operative 
brakes, the need to immediately set-out and handle cars with defective 
brakes for repair is unnecessary. There is also no safety need to 
require a railroad to incur the expense and delay involved with cutting 
the defective car out of the train. Currently, freight cars with 
defective mechanical conditions are permitted to be hauled long-
distances for repair. See 49 CFR 215.9. In light of the technological 
advances provided by ECP brake systems, it appears logical and 
necessary to permit more flexibility in moving equipment with defective 
brakes when equipped with ECP brakes and hauled in a train operating in 
ECP brake mode. However, the language of 49 U.S.C. 20303, prevents FRA 
from providing this flexibility.
    The aforementioned requirements governing conventional pneumatic 
braked trains may offset the increased safety and efficiency benefits 
afforded by ECP brakes, thus eliminating the incentives for rail 
operators to implement ECP brake technologies. To encourage 
implementation without hindering safety, FRA proposes to invoke its 
discretionary authority under 49 U.S.C. 20306 to exempt ECP brake 
equipped trains from the specific statutory requirements contained in 
49 U.S.C. 20303. The requirements for moving defective equipment were 
created over a century ago, during the infancy of pneumatic brakes and 
before all cars were equipped with power brakes. With many more reasons 
to stop train operation along tracks with frequent repair shops and 
exponentially more employees, the legislative drafters of that time 
could not have envisioned the type of safer and more efficient 
technologies available today.
    Recognizing the importance of upgrading rail technologies, Congress 
in 1980 passed the Rock Island Railroad Transition and Employee 
Assistance Act (the ``Rock Island Act''), which, inter alia, provides 
statutory relief for the implementation of new technologies. More 
specifically, when certain statutory requirements preclude the 
development or implementation of more efficient railroad transportation 
equipment or other transportation innovations, the applicable section 
o