Passengers have waited up to 15 hours for flights earlier this week at major airports in the eastern United States, although airport officials say the situation is rapidly improving.

Bottlenecks appear worst at the major northeastern airports, such as New York's LaGuardia and John F. Kennedy. The recent disruption of transatlantic traffic created backlogs and problems of "sheer capacity," said a spokesman for the Airport Operators' Council International (AOCI), a clearinghouse for information about airports.

Earlier this week, passengers at LaGuardia and Kennedy waited from 30 minutes to 15 hours for flights, the spokesman said.

The Miami airport also reported delays of up to 14 hours, although there was no serious crowding at the terminal, the spokesman said.

The Boston airport yesterday reported minimal delays, although earlier this week passengers had encountered delays averaging one to three hours, with some waiting as long as 14 hours for flights, she said.

Airports at Chicago, Philadelphia, Cleveland and Detroit yesterday reported they also had delays but were getting back to normal.

Once passengers board the planes, "control tower" delays -- those between leaving the gate and takeoff -- can be measured in minutes. FAA said the longest delays yesterday were at the Denver airport, averaging about 50 minutes. The Denver airport has been hampered by bad weather, the AOCI spokesman said.

Departure delays at LaGuardia yesterday averaged 30 minutes, and Chicago's O'Hare airport averaged between 20 and 35 minutes. Airport officials generally seem "real optimistic" about the situation, the AOCI spokesman said. "They say it's certainly better than last week and getting better all the time."

In fact, Atlanta's airport, one of the nation's busiest, is asking for more traffic, she said. Los Angeles International, also among the busiest airports, was processing 98 percent of its normally scheduled flights yesterday, an airport official said.

One reason traffic flow problems are not as severe in the south is that there may be less support there for striking Professional Air Traffic Controllers Organization, leaving more controllers on their jobs, the AOCI spokesman said.