WASHINGTON - Metrorail passengers frustrated with jerkier rides and longer waits for trains after June's Red Line crash can expect those irritations to continue indefinitely as operators run every train in the system manually, the Washington Post reports.
Metro does not have precise data on how much slower the system is moving, but spokeswoman Lisa Farbstein said trains controlled by operators tend to spend more time at station platforms and take more time to accelerate than do trains run by computers.
"You could lose a couple of minutes from one end [of a line] to the other," she said. "If it's 10 seconds between each station, it does add up."
In the weeks since the June 22 crash, in which nine people were killed and 80 were injured, top Metro officials have described continuous manual operation as a safety precaution. But federal investigators have said the automatic control system designed to prevent crashes can be problematic regardless of whether trains are operating under manual or automatic control.
The NTSB has said that it appears that Metro's automatic train control system failed to detect a stopped train June 22 and that an approaching train did not receive a command to stop on the track between the Takoma and Fort Totten stations.
Manual control brings with it another set of problems. "Operating a train is a very repetitive task," said Elisa M. Nichols, a transit system safety consultant in Kensington. "You do the same thing all the time. There's complacency. [The operator] could be tired. He could be preoccupied. He could be taking medication. There is nothing inherently unsafe about operating in manual mode, but you introduce more risk."
Metro General Manager John B. Catoe Jr. reiterated last week that trains will not run automatically again until he is satisfied that "all the aspects of what occurred on June 22 have been corrected."
That might take years. The National Transportation Safety Board is probably months away from issuing a final report on the cause of the accident, and making fixes that federal investigators have recommended, such as replacing the oldest cars in the fleet with more-crashworthy ones, would cost hundreds of millions of dollars that Metro does not have.
In July, the NTSB urged Metro to install a real-time, continuous backup for the system. Metro began talks with vendors after the recommendation but does not have an estimate for what such a system would cost or how long it would take to install.
The idea behind staying on manual control is that operators will be more engaged in running the trains and can exercise their judgment if something goes wrong. But even with manual control, operators depend on the train control system to tell them how far ahead the next train is. In automatic, the computer sets the train's speed. In manual, the operator sets the speed but does so based on information the computer provides.
"So, inherently, the design problem that caused the accident, if that's what it was, is still present in the system," said Piers Connor, a train systems expert from England who has advised railways around the world. "There is a basic design fault which is inherent in the system, and they've got to design that out."
The amount of time a rider has to wait for a train varies more when the system is on manual. And, like a driver on a congested road, an operator must brake whenever the train ahead is going slower. That contributes to the jerkier rides across the system.
"The automatic train system itself is very precise," said Martin Schroeder, chief engineer for the American Public Transportation Association. "When you have humans trying to replicate that, with their hand on the throttle, it results in longer time between trains."
Because manual operation demands more concentration, the union that represents Metro's train operators is pushing to ensure that members get proper break times. The contract limits operator time at the controls to 5 hours and 45 minutes before requiring a 20-minute break.
"There's that strain on your mind, paying attention to what you're doing," said Anthony Wayne Garland, the chief safety officer for Amalgamated Transit Union Local 689. "You dot your I's and cross your T's. So, naturally, that takes more wear on your mental capacity during the course of the day, but that's what we have right now."
Metro has operated its trains in manual mode for extended periods before. Trains ran manually from March 1999 to November 2000 after the transit agency discovered that relays along the tracks were failing. Those relays, each about the size of a hardcover book, control switches for changing tracks, adjust each train's speed, and control signals that tell operators to go or stop.
After four worrisome incidents, including one in which the automated system ordered a train to travel 45 mph in an area where the speed limit was 15 mph, Metro replaced thousands of the components.
Metro spokesman Steven Taubenkibel said trains generally operated in manual mode during the first hour of service every morning before the June crash to make sure work crews had cleared the tracks. In any area where maintenance was being performed, operators controlled trains manually.
"While the system has always been designed for automatic train operations, there's never really been a period where we've been in automatic 24-7," Taubenkibel said.
Before the June crash, operators had taken on additional tasks because of problems related to automatic operation.
Since April 2008, operators have manually opened and closed rail car doors at every station. Metro implemented that policy after doors opened on the wrong side of the platform four times in a 100-day period because of what officials described as a malfunction in the automatic train control system. Manual operation of the doors has not been error-free.
At least three times this year, operators have opened doors on the wrong side of the platform, and at least 17 times from March to May, operators opened doors on rail cars that had stopped short of the platform.
Automatic operation has contributed to other problems.
After a January 1996 crash in a snowstorm killed a train operator at the Shady Grove Station, the NTSB concluded that Metro was relying too heavily on its computerized operating system. The operator, Darel W. Callands, was unable to stop his automatically operated train on icy tracks and crashed into a parked train, investigators said.
The then-operations chief had ordered operators to use manual controls only in emergencies because he assumed that excessive manual braking was causing premature wear to wheels, a departure from standard Metro safety practices that specified manual operation in rainy or icy conditions.
In recent years, Metro operators have operated manually on above-ground tracks during inclement weather, Taubenkibel said.
Other systems rely on manual operation more than Washington's because they were built long before technology allowed the sort of automation available to Metro's engineers in the 1970s.
New York City Transit, the country's largest rail network, operates trains manually on all but one line. Elsewhere, train operators control the speed and braking of trains in response to signals that are similar to traffic lights. If a train enters a section of track it should not be on, a century-old technology called a trip stop forces the train to slow down.
Automatic control systems that were developed after the invention of computers are far more advanced. Schroeder, the chief engineer for the APTA, said those systems are safe, despite the June 22 crash.
"It's a system that evolved over a long time," he said. "A lot of sophistication has been added to these systems."
(This item appeared Aug. 19, 2009, in the Washington Post.)
NTSB Advisory National Transportation Safety Board Washington, DC 20594 July 29, 2009
FOURTH UPDATE ON NTSB INVESTIGATION INTO COLLISION OF TWO METRORAIL TRAINS IN WASHINGTON, D.C.
The National Transportation Safety Board continues to make progress in its investigation of the June 22, 2009, collision of two Washington Metropolitan Area Transit Authority (WMATA) trains on the Red Line in Washington, D.C. The Board has developed the following factual information:
To date, significant work has been done to determine why the presence of train 214 was not identified on the train control circuit that allowed train 112 to crash into it. The NTSB's accident investigation is continuing, and more work is needed to fully understand why the train control system did not perform as designed.
Most of the electrical components on this system are original equipment from the mid-1970s. NTSB investigators, along with personnel from WMATA, the Federal Transit Administration, and the equipment manufacturers, are carefully examining all components to understand how any change or degradation in component performance might affect the train control system.
The train control room at Fort Totten Station contains dozens of modules for the track circuits north and south of the station. Investigators have been concentrating on the two track circuit modules for the accident site. Both of these modules contain twenty circuit boards with capacitors, resistors, and transistors. Each of these components is being tested extensively to determine component operating values, tolerances, circuit interactions, and the effect of their performance on the train control system. As part of the process for replacing impedance bonds at the site before the accident, adjustments were made to track circuit signal strength. The investigation is evaluating any effect that these track circuit adjustments may have had on the performance of track circuit modules located at Fort Totten.
The two modules that were in place at the time of the accident were removed from the Fort Totten train control room for examination by the accident investigation team at WMATA's laboratory. Two replacement modules were installed at the Fort Totten station that showed similar anomalies and they were removed and preserved for further testing. Two additional modules were then installed by WMATA at the Fort Totten station that did not display these anomalies.
The NTSB's investigation will continue at the accident site at Fort Totten, at WMATA's laboratory facility in Landover, Maryland, and at WMATA's Operations Control Center to determine why the automatic train control system failed to prevent the collision on June 22, 2009.
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-- Edited by Calvin on Wednesday 19th of August 2009 10:45:58 AM
