Equipment Failures

Space shuttle Discovery was hit by a TV blackout Wednesday that could deprive NASA of live images of the final shuttle linkup with Mir today. NASA scrambled to work around the failure, which more than anything else was a PR nightmare. Because of the unprecedented trouble, NASA expects little if any live television of the docking or the rest of the 10-day mission to bring home Andrew Thomas, the last American to live aboard the Russian space station.

A broad outage of Pacific Bell Mobile Services left tens of thousands of Southern Californians without the use of their mobile phones Friday. The digital PCS phone service gradually was being restored by late afternoon, after about six hours on the blink. But in the meantime, customers who use their phones for everything from conducting business to staying in touch with family members had to do without one of the Southland's signature gadgets.

America's electronic tether--the pager--has returned to power, and its tiny chirping call can again be heard singing from backpacks, waistbands and purses nationwide. But last month's unprecedented satellite outage, which disrupted millions of pagers and television transmissions, is still reverberating with paging companies and broadcasters alike.

Reacting to suspect wiring found in the wreckage of TWA Flight 800 and on other planes, federal officials Tuesday called for prompt inspections of Boeing 747s like the one that crashed off Long Island, N.Y., in 1996, killing all 230 on board.

Fixes to prevent the sort of fuel tank explosion that brought down Trans World Airlines Flight 800, a Boeing 747 jumbo jet, were proposed Thursday for another Boeing jetliner, the widely used 737. The estimated cost of complying with the proposal to rework the fuel-sensor wiring systems on 1,140 of the U.S.-registered, narrow-body 737s is about $41 million.

Fixes to prevent the sort of fuel tank explosion that in 1996 brought down Trans World Airlines Flight 800, a Boeing 747 jumbo jet, were proposed Thursday for another Boeing jetliner, the widely used 737. The estimated cost of complying with the proposal to rework the fuel-sensor wiring systems on 1,140 of the U.S.-registered, narrow-body 737s is about $41 million.

A crucial data processor failed just hours before space shuttle Columbia was to lift off, forcing a one-day delay and the hurried replacement of 1,514 crickets and 18 pregnant mice. NASA said it would replace the processor and try again today to send Columbia on a two-week mission to study the nervous systems of seven astronauts and more than 2,000 animals. The crickets aboard Columbia, nearly half of them still in the egg stage, had to be replaced with fresh substitutes.

A routing cable damaged by a loose train wheel shut down Denver International Airport's computerized passenger trains for about seven hours Sunday, creating mass confusion among thousands of travelers. Passengers were shuttled to and from outlying concourses on 30 buses until the train system was back in operation in the early evening. "It was hot. No air conditioning," said passenger Judith Fisher. "The emergency phones weren't working. Nobody seems to know what's going on."

Space shuttle Columbia's patched-up life support system was working normally, allowing astronauts to continue research into the brain and nervous system, NASA officials at Kennedy Space Center said. "All of Columbia's systems continue to function perfectly, including the revamped carbon dioxide removal system," NASA's mission control commentator Rob Navias said.