T traps 60,000, raises doubts

"You'd think we are living in a Third World country," said Robert Christian, 75, a retiree stuck for 10 minutes between the Kenmore and Hynes stations on the Green Line. "This happens with considerable frequency. It just gets you enraged."

Yesterday's outage was more than the usual signal problem on a single line. A stray current tripped a central breaker in South Boston, knocking out the system that guides trains and trolleys along their routes, extinguishing lights in the tunnels and many stations, and switching off the fare collection system.

The visual grid inside the MBTA's operations center, the one that tells train dispatchers where every subway car in Greater Boston is located, lost connection with all trains at 8:50 a.m. and did not get back online for about 30 minutes.

Richard J. Leary, the T's chief operating officer, said the error that led to the loss in power was "inadvertent," caused by MBTA workers and contractors doing scheduled maintenance on a pair of 115,000-volt cables that feed power to the T. But the results raised concerns that went beyond yesterday's train delays.

"First of all, what it shows is how important real redundancy is, redundancy that allows you to have completely separate systems that can actually work," said Elaine Kamarck, a former Clinton administration official who has written about homeland security.

Kamarck, who lectures on government at the Kennedy School of Government at Harvard and uses the Red Line, said terrorist attacks in Madrid and London have demonstrated the importance of shoring up public transit and other potential targets.

"Whenever something like this happens, what you realize is how a small thing can cause real chaos and those are exactly the type of little windows of opportunity that terrorists look for," she said.

Leary maintained that the system is redundant. The T has back-up generators, but did not use them because workers were able to reset the tripped breaker within 7 minutes, reestablishing full power within 30 minutes, Leary said.

The two cables the crews were working on are intended to back each other up to prevent precisely the sort of accident that happened yesterday. But one had been removed from service while testing took place. It was this testing that inadvertently tripped the breaker by inserting a cable that workers did not realize was electrified, said Sean Carney, an MBTA power division engineer.

Leary said the T will review its preventive maintenance practices, including decisions to perform tests during rush hour, to ensure that this never happens again. He also said the T would investigate whether passengers stuck in trains and at stations were adequately informed. Radio dispatchers were supposed to have told train operators to make announcements explaining what had happened.

"I'd like to apologize to our customers," Leary said. "We'll do better." Leary, who has worked at the T for 25 years, said he could not recall any previous systemwide power failure.

The MBTA's general manager, Daniel A. Grabauskas, did not attend the press conference.

Yesterday's relatively brief stoppage continued a disastrous month for the Massachusetts Bay Transportation Authority, kicked off by a rear-end Green Line crash that injured nearly 50 people on May 8.

The outage meant dispatchers had to control 54 subway trains manually, using a radio system that allows cars to move forward only after an employee on the tracks gives the all-clear. The 78 Green Line trolleys running at the time - which depend on system of red, yellow, and green traffic lights - also depended on manual operators on the tracks. Service on that line, which was most heavily affected, was not restored to normal operations for more than an hour.

The manual system the T resorted to yesterday is designed to prevent cars from crashing into each other when the signals go down. Red, Orange, and Blue lines automatically halt when the power goes out. Green Line traffic signals default to a double-red, a warning to drivers that they should not proceed.

"It's extremely slow," said Sean McCarthy, who heads the T's operations center. "It has to be done as safe as humanly possible."

Though the outage cut to the heart of the T's ability to operate, it did not cut off power entirely. Air-conditioning and lights on trains and trolleys continued to work, as did almost all of the third rail and overhead power lines that propel trains and trolleys. There was one exception: About 30 riders on a powerless Red Line train had to be evacuated and walked about 70 feet along the tracks to reach Shawmut Station, officials said.

Some passengers took the delays of 15 to 30 minutes in stride. Others had their days completely altered.

"We were waiting for over an hour," said Heidi Boulogne of the South End, who was chaperoning a group of about 15 kindergarteners to a puppet show in Brookline. "But now we're too late. It's too bad; we we're looking forward to this. Maybe the T will pay for another show."

John R. Ellement and Andrew Ryan of the Globe staff and Globe correspondent Stewart Bishop contributed to this report. Noah Bierman can be reached at nbierman@globe.com.