The highest concentration of cancelations occurred at the American Airlines' hub in Dallas and Chicago. Here in the Bay Area there were seven cancelations at SFO, ten at San Jose Mineta, and two in Oakland. These 300 MD-80's account for nearly half of their entire fleet. So far they have found 80 that need medication, 20 are already back in the air.
American Airlines' fleet of 300 MD-80's had to be re-inspected to make sure electrical wiring inside the wheel well was properly secured.
During an FAA audit, questions were raised about whether a bundle of wires were installed according to FAA requirements.
ABC7 Aviation Consultant Ron Wilson says improperly secured wires can lead to disaster.
"If you chafe a wire down or the insulation off of the wire itself, it can go to ground and cause a fire or a failure of a major component of the airplane," said Wilson.
But ABC News Aviation Expert John Nance says there was probably no imminent danger.
"These are inspections done so far in advance of when there's anything critical. It's the safety system working as it should, not unsafe airlines being pulled off the line," said Nance.
American says it's trying to help passengers on cancelled flights by putting them on other American flights or other airlines altogether. Don Rathjen was trying to get from SFO to Boston for a convention.
"Probably won't get there in time and I've got people waiting for stuff I have with me," said Rathjen.
Faulty wiring was blamed for the 1996 TWA Flight 800 crash off Long Island that killed 230 people.
In 2000, the FAA ordered wiring inspections for planes that were more than 20 years old.
Wilson says the nation's fleet of aircraft is aging, but tough maintenance requirements mean plane parts are constantly updated, making even old planes like new.
"They replace engines, internal parts, portions of the skin. Anything that looks damaged or looks deteriorated they'll replace it and over time the replacement of this stuff virtually replaces the airplane," said Wilson.
The penalties for failing to keep up with maintenance are steep, earlier this month Southwest was fined a record $10.2 million dollars for inspection lapses.
Wilson believes American Airlines MD-80's will now be among the safest planes in the nation's already safe fleet.
"The modern American fleet is I think perfectly safe. The maintenance is much more stringent in the US than other parts of the world," said Wilson.
American Airlines says part of the delay in getting these inspections done are getting the airplanes at the airports that have the appropriate technicians and equipment to do these inspections. In some cases they actually had to fly planes to certain airports or flight technicians to airplanes. American says at this point it doesn't know if these cancelations will continue through until Thursday.
