The audit will begin next month, said American spokesman Tim Wagner. It will primarily involve a detailed review of safety data, including evaluation of maintenance and flight manuals, records and other documents, rather than inspections of airplanes, said Alison Duquesne, a spokeswoman for the Federal Aviation Administration.
She said the agency is still putting its team of investigators together, and is still working with American officials on how to best conduct the audit.
The in-depth review comes after months of criticism of maintenance practices at the major airlines. Last year, the FAA grounded jets at American, Southwest Airlines, Delta Air Lines and others for emergency inspections after it was determined some inspections weren't properly conducted.
"We told Congress last year that we would be doing some focused audits of the major air carriers," she said. The FAA has already completed similar reviews at Dallas-based Southwest Airlines and Houston-based Continental Airlines.
The review will look at all aspects of American's operations, including flight, ground operations and maintenance.
A March 20 letter from officials with the Transport Workers Union, which represents American's mechanics, states that the audit was precipitated by three factors:
Problems the FAA unearthed last year with wiring in the wheel wells of MD-80 aircraft. The agency forced American to ground its entire fleet of MD-80s for a week to check the wiring, which resulted in more than 3,000 canceled flights.
The termination of a safety program that allowed pilots to report safety-related issues without fear of reprisal from the airline or the FAA. That program ended after American and the Allied Pilots Association failed to negotiate terms for a renewal.
An increase in safety reports issued to mechanics last year.
"I think we're well prepared (for the audit)," Wagner said. "It's an extension of what the FAA does with us every day."
At a briefing for union leaders, company officials said the audit will take six months, and could result in fines if problems are found.
American said "if the FAA finds things that fines will likely be the result, and seemed to imply that those costs would likely result in further headcount reductions," wrote Bob Owens, president of TWU Local 562, in the letter to union members. "While I certainly hope we come out of the audit well, I find this claim incredulous."
Fines are a possibility, said FAA spokeswoman Duquette, but the agency could also use a wide slate of tools to correct any problems.
Airline safety has been in the spotlight during the past year. In addition to the inspection problems at Southwest, American and other carriers last year, several high-profile incidents, such as the January landing of a U.S. Airways jet in the Hudson River, and the February crash of a Continental Express flight that killed 50 people, have some passengers increasingly worried about safety during flights.
A congressional investigation led by U.S. Rep. James Oberstar, D-Minn., accused FAA officials of having a "cozy relationship" with Dallas-based Southwest that led to lax safety standards.
The FAA fined Southwest a record $10.2 million last year for inspection lapses, and later lowered the full amount to $7.5 million.