IV. Application Request

A. Purpose of Request

BART currently uses the Sequential Occupancy Release System (SORS) for monitoring and controlling train separation during revenue service. BART's application seeks authority to modify the existing train system with an overlay subsystem that will enable trains to operate at closer headways while maintaining no less than the existing degree of safety. BART contends the benefits of the proposed Advanced Automatic Train Control System are that (1) train location is more precise and (2) braking is less severe and more controlled with reduced probability for wheel/rail slippage. The Advanced Automatic Train Control System will transfer the motion control function of train operations from the original track circuit based system to a radio based system working in conjunction with station based computers.

BART explains that the proposed system uses a network of radio sets installed on the train control cars and at intervals along the wayside ranging from 1/3 of a mile to one mile apart. BART states that the radio sets exchange reports and commands between the lead and tail control cars of the trains and the station computer. The station computer decodes the data, computes positions of trains, references track data, then calculates and sends back optimized motion and control commands to the train.

The application states that BART has begun developing the technology, both software and hardware, and tested preliminary versions in a test track demonstration. BART proposes to implement the Advanced Automatic Train Control System as a three-phase project.

Phase One involves interfacing new Advanced Automatic Train Control System station computer and communications technology with the existing vehicle and station control equipment at the test track and making necessary modifications to such equipment to accommodate the Advanced Automatic Train Control System operation.

In Phase Two, BART contemplates full development of the system hardware and software for revenue service operation. Phase Two entails a pilot test of the project, involving installation of Advanced Automatic Train Control System operation equipment on 10 cars and in two stations, Lake Merritt and Fruitvale, and is currently underway. Phase Two activities will entail the operation of modified equipment during revenue hours on passenger carrying trains, to collect communications and train location functions data. However, movement of trains will continue to be controlled by existing track circuit equipment.

During Phase Two, existing equipment will be modified to achieve hybrid operation in which the vehicle will respond (1) to motion control commands sent by the Advanced Automatic Train Control System through the radio network or, in the absence of such commands, and (2) to speed commands sent by the existing track circuits. In revenue hour tests, trains will be under the control of the usual track circuits, but with software modified to allow collection of Advanced Automatic Train Control System related data. BART states that it will notify the Commission prior to the start of such tests.

The application states that Phase Three entails the manufacture and installation of Advanced Automatic Train Control System equipment for revenue service on all control cars, and on 22 miles of BART's system: the A-Line from Fruitvale south through Bayfair; in the Lake Merritt area to MacArthur Station interface; and the M-Line through Daly City.

The application requests deviations (referred to as variances by BART and in the Settlement Agreement) from several provisions of GO 127, which governs Automatic Train Control design and operation. BART states that GO 127 currently mandates the use of several technologies which prevailed in 1972, but which are superceded by the Advanced Automatic Train Control System. Mandated technologies include (1) track circuits for communications and train detection, which BART contends are now being replaced by radio communication and radio ranging, respectively; and (2) fixed-rate braking, which is being replaced by controlled variable braking.

GO 127, by its own terms, allows for the Commission to grant deviations from the rules contained in the general order. Requests are to provide a full statement of the reasons justifying the requested deviations and any deviation so granted is to be limited to the particular case covered by the request. (GO 127, Rule 5.1.) It is not the purpose of the proceeding to formally amend GO 127. In the event it is believed amendment of GO 127 is appropriate, this will be initiated either by a formal Commission rulemaking proceeding or by a party petition pursuant to Pub. Util. Code § 1708.5.

BART's application provides specific methodologies for testing and implementing the Advanced Automatic Train Control System. The application states that stringent safety requirements are a major focus of the program. BART states that it will review and submit to the Commission all required safety documents.

B. Request as Initially Filed

Initially, BART sought deviations of GO 127 in the following respects, with additions underlined and deletions shown as strikeout:

Section 1.10 to be modified to read as follows:

Fail-Safe - A characteristic of a system which ensures that any malfunction affecting safety will cause the system to revert, within probabilistically-defined system Mean Time Between Hazard, to a state that it is known to be safe.

Section 3.3 to be modified to read as follows:

Trains shall be detected continuously. The maximum length of a train detection zone shall not exceed 5,000 feet. If the train detection equipment becomes incapable of detecting the presence of a train in a zone or zones, the effect shall indicate that zone or zones as occupied. Train location shall be determined periodically by a Station Computer-based system that shall store last-known occupancies, and use them along with civil speed limits and other track data to compute safe speed and deceleration commands for following trains.

Section 3.8(a) to be modified to read as follows:

If the speed of a train broaches the safe speed-distance profile, the system shall immediately command an accelerometer-controlled brake rate calculated to be safe, and shall monitor the progress of the trains to assure maintenance of the commanded rate within prescribed limits. If the system detects that the prescribed limits are broached, the system shall immediately and automatically cause an open-loop brake application which shall be maintained at least until the train speed reduces to a value below the safe speed-distance profile.

Section 3.8(b) to be modified to read as follows:

The safe braking distance shall be a curve based on the track and wayside structure requirements and shall apply to each track throughout the length of the system. The profile transition from a lower speed limit to a higher speed limit shall not rise from the lower value until the rear of a train clears the lower speed limit. The profile transition from a higher speed limit to a lower speed limit shall be a continuous curve beginning at a point preceding the entrance to the lower speed limit by a distance at least equal to the sum of the maximum open-loop braking distance and the distance traveled in 3.0 seconds at the higher speed limit, and the equipment reaction time distance at the higher speed limit, and ending at a point preceding the entrance to the lower speed limit by a distance at least equal to the sum of the distance traveled in 3.0 seconds at the lower speed limit, and the equipment reaction time distance at the loser speed limit. sufficiently large to offer safe separation under adverse conditions.

BART also sought the following changes to D.91846.

Section 1.A.a of D.91846 is modified to read as follows:

BART shall operate the SORS as a backup for the primary detection system during both revenue and nonrevenue service. SORS may be disabled during nonrevenue service only when adequate train separation is assured by Central Control operating procedures, as authorized by the Commission staff. track-circuit based system of train detection unless the trains in the associated control zone are all under AATC system Control Mode control, in which case train detection, location and train separation shall be enforced by the AATC system.

The application also sought approval of the Phase Two testing, including revenue service testing of the Advanced Automatic Train Control System and approval of the Phase Three revenue service as described above.

C. Position of Rail Safety on Initial Request

In its response to BART's application, Rail Safety asserted that an evidentiary hearing might be necessary to resolve issues raised by BART's application, including those that might arise during the process of certifying the safety of the Advanced Automatic Train Control System. Rail Safety`s response states that BART's application lacked information necessary for Rail Safety to oversee the safety of the proposed project. Specifically, Rail Safety objected that BART had not yet submitted its Advanced Automatic Train Control System Safety Certification Program Plan to the Commission. Rail Safety contended that it could not make a recommendation that BART institute the Advanced Automatic Train Control System in revenue service until it had received, reviewed and concurred with BART's Advanced Automatic Train Control System Safety Certification Report. However, Rail Safety indicated its support for granting the General Order deviations requested, concurring that the technology in place when the current version was adopted was very different from what was now available.

D. Initial Settlement Proposal

On November 18, 1999, BART and Rail Safety filed a motion for adoption of what is identified as a settlement. The settlement proposes deviations to certain provisions of GO 127 and D.98146 for purposes of enabling BART to use the new technology required by its proposed Advanced Automatic Train Control System. These are somewhat different than those deviations requested in the application.

A copy of the Safety Certification Plan was provided to Rail Safety by BART transmittal letter dated September 16, 1999, prior to the initial settlement proposal. Counsel for BART noted at the March 23, 2000 PHC that a more recent copy of this Safety Certification Plan would be provided to Rail Safety on, or soon after the PHC. It was also noted that there would be additional revisions to the Safety Certification Plan.

In the initial settlement, the Parties agreed that BART would provide Rail Safety with a copy of the most recent draft of the Safety Certification Plan setting forth the tasks, goals, documents, schedules, and personnel intended to ensure the safe development of the technology necessary for revenue service of the Advanced Automatic Train Control System and that Rail Safety would have 14 days to file with the Commission comments on that plan. The Parties further agreed that any changes in the Safety Certification Plan would be provided to Rail Safety within two days of being finalized and Rail Safety would have 14 days to file any comments on such changes with the Commission.

The Parties agreed that BART would provide Rail Safety a schedule indicating the time and place of each audit to be performed by BART's Independent Safety Auditor regarding development of the Advanced Automatic Train Control System and notice at least two weeks in advance of any change in that schedule. The Parties further agreed that BART will provide Rail Safety an unedited copy of any report prepared by the Independent Safety Auditor of any such audit within two days of receiving it.

Finally, the Parties agreed that, on completion of Test Gate 3MD, as described in the Safety Certification Plan, BART will report to the Commission on the status of the development of technology necessary for Revenue Service of Advanced Automatic Train Control System and that Rail Safety will have 30 days to file comments on that report. The Parties further agreed that at that time they would address the need for BART to submit a report on completion on any subsequent Test Gate.

E. Final Settlement Proposal

On May 10, 2000, BART and Rail Safety filed a motion for approval of a new settlement, constituting what is now the Settlement Agreement before the Commission for approval. The settlement provisions are set forth as follows:

BART and Rail Safety stipulate that BART should be able to use the Advanced Automatic Train Control System in revenue service during Phase Two of the project subject to "execution" by BART of the Safety Certification Plan attached to the Settlement Agreement as Exhibit A, and verification by the Rail Safety unit "that each element detailed therein has been completed in accordance with the Safety Oversight Plan" attached to the Settlement Agreement as Exhibit B.

Both parties stipulate that Rail Safety has accepted the Safety Certification Plan, that the plan is complete and that it provides sufficient opportunity for Rail Safety to carry out it responsibilities.

The parties recommend deviations from GO 127, that are again somewhat different from those requested in the application. The recommended changes are as follows:

Section 1.10 should be revised to read:

Failsafe - A characteristic of a system which ensures that any malfunction affecting safety will cause the system to revert to a state that is known to be safe either has no known mechanism that can lead to unsafe operation, or if the absence of such unsafe mechanisms cannot be proven, can be shown by analysis that the equipment will not fail in an unsafe manner more frequently than the criteria established by the mean time between hazards for the system or component.

Section 3.3 should be revised to read:

Trains shall be detected continuously. The maximum length of a train detection zone shall not exceed 5000 feet. If the train detection equipment becomes incapable of detecting the presence of a train in a zone or zones, the effect shall indicate that zone or zones as occupied. The AATCS shall locate each train continuously, store information on its last known location, and use this information to compute safe speed and deceleration for each following train.

Section 3.8 should be revised to read:

The train protection system AATCS shall ensure that the speed of each trains train at each location is always less that the safe speed distance profile over the entire system determined according to physical constraints of the system and by the distance necessary to brake safely before reaching any closed interlocking gate or a detected obstacle.

(a) The Train Protection System If the speed of a train broaches the safe speed-distance profile, the system shall immediately and automatically cause an open-loop brake application which shall be maintained at least until the train speed reduces to a value below the safe speed-distance profile command any train exceeding safe speed to brake at a rate governed by the model and associated parameters specified in Exhibit A of the Safety Certification Plan and to maintain such braking until the train slows below the safe speed.

(b) The AATCS shall not permit any train to violate the Civil Speed Limit prevailing for any portion of track over which it is traveling The safe speed-distance profile shall be a curve based on the track and wayside structure requirements and shall apply to each track throughout the length of the system. The profile transition from a lower speed limit to a higher speed limit shall not rise from the lower value until the rear of a train clears the lower speed limit. The profile transition from a higher speed limit to a lower speed limit shall be continuous curve beginning at a point preceding the entrance to the lower speed limit by a distance at least equal to the sum of the maximum open-loop braking distance and the distance traveled in 3.0 seconds at the higher speed limit, and the equipment reaction time distance at the higher speed limit, and ending at a point preceding the entrance to the lower speed limit by a distance at least equal to the sum of the distance traveled in 3.0 seconds at the lower speed limit, and the equipment reaction time distance at the lower speed limit.

(c) If the ATC speed limit is zero mph, the train protection system shall maintain an open-loop brake call after the train stops and until the train protection system changes the ATC speed limit.

(d) For purposes of train speed detection, the measurement of speed shall continuously represent true train speed within plus or minus 0.5 mph and independent of wheel wear.

(e) Zero speed shall be detected and used to prevent door operation and direction reversal when a train is moving.

(f) The train protection system shall initiate emergency braking in the event a train is detected to be rolling back. The emergency braking shall be applied before roll-back speed exceeds 1.0 mph, or before roll-back distance exceeds 30 inches.

Section 3.9 should be revised to read:

The parties also stipulate to a modification of D.91846 to the effect that notwithstanding Ordering Paragraph 1.A. of that decision, BART should be authorized to suspend its Sequential Occupancy Release System (SORS) for any portion of track controlled by AATCS.

The parties have also reached agreement on various notification situations. If there are any changes made to the Safety Certification Plan, BART will provide the Rail Safety unit notice of the changes within two days and the Rail Safety unit will have 14 calendar days to notify BART of any objections to the changes. BART agrees to not implement any changes without the agreement of the Rail Safety unit.

With regard to the Independent Safety Auditor, BART agrees to provide the Rail Safety unit a schedule indicating the time and place for each audit to be performed, at least two weeks' notice of any changes in that schedule, and unedited copies of any report prepared by the Independent Safety Auditor of any such audit within two days.

BART is to also file an advice letter with the commission upon completion of Safety Certification "Gates" defined in the Safety Certification Plan, along with a copy of each required certificate of conformance, allowing the Rail Safety unit two weeks to verify whether they were properly completed.

Finally, BART withdraws its request for approval of Phase Three revenue service and will seek its approval at a later time.

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