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US air traffic delayed at 11 airports

Computer glitch, weather to blame

Yesterday's delays won't help US airlines on-time record. Through April, US carriers had just a 72.5 percent on-time rate. (Frank Franklin II/Associated Press)

DALLAS -- US air traffic slowed yesterday at 11 major airports due to a computer malfunction and thunderstorms, adding to the year's record delays, the Federal Aviation Administration said.

The affected airports included New York's LaGuardia and Kennedy; New Jersey's Newark and Teterboro; Dallas-Fort Worth; Atlanta, Cleveland, and Phoenix, the FAA said on its website.

"There are 50 airplanes on the ground at this moment" at LaGuardia, Doug Church, spokesman for the National Air Traffic Controllers Association, said at about 4:20 p.m. He said his information was based on talking with controllers. "It's probably the worst day at LaGuardia this year."

US airlines managed only 72.5 percent of flights on time this year through April, the worst since the federal government began keeping track in the current format in 1995.

Delays may extend into the summer travel season due to high traffic volumes and storms, the FAA and analysts have said.

Failures in FAA flight-plan computers at 6:57 a.m. in Atlanta and later in Salt Lake City forced the agency to process flight plans manually, causing delays in the traffic system, spokesman Paul Takemoto said.

"The problem has since been resolved, but there are residual delays in LaGuardia and Philadelphia that are compounded by bad weather," Takemoto said.

Delays in cities including Chicago and Detroit were due to bad weather, not the equipment failure, Takemoto said.

AMR Corp.'s American Airlines has had about 50 cancellations on the East Coast, with 11 at LaGuardia, spokesman Tim Wagner said.

Flights by Delta Air Lines Inc., the third-largest US carrier, were affected more by bad weather than the FAA's computer failure, spokeswoman Betsy Talton said.

"We are seeing impact today from thunderstorms that are causing delays in the Northeast of about two hours," Talton said.

Steve Coleman, a spokesman for the Port Authority of New York and New Jersey, said delays were running two to three hours at LaGuardia, Kennedy, and Newark, the three major New York-area airports.