Mar. 27 — In the face of unprecedented federal scrutiny of airline maintenance, airlines are taking dramatic steps to prove compliance, including canceling flights to redo work they may have already performed.
On Wednesday, American Airlines canceled about 300 flights after regulators questioned the way the airline had secured wires on its McDonnell Douglas MD-80 jets.
A few hours later, Delta Air Lines announced that it would recheck its fleet of MD-80s and MD-90s, a move that could require it to cancel flights in the coming days.
This comes after Southwest Airlines' cancellation of 126 flights on March 12 and American Eagle's 15-flight cancellation Friday.
Experts said these disruptions could be the first of many, given the sudden focus on complex federal airworthiness directives and the need to show compliance before a congressional hearing scheduled for April 3.
"At the very least, they are going to find some paperwork issues that need to be revisited," said John Goglia, an aviation maintenance expert and former member of the National Transportation Safety Board. "Sometimes it's easier to go redo the AD [inspection] than to go through the reams of paperwork to prove that you've already done it."
In the post-deregulation era, airworthiness directives are the Federal Aviation Administration's strongest tool to prescribe inspections and repairs. The FAA issues the lengthy documents to correct potential safety problems. The government can sanction carriers that don't comply with the rules.
In fact, the FAA fined Southwest $10.2 million on March 6. A federal investigation found that Southwest continued to fly jets that missed required federal inspections.
Since then, Southwest, American, American Eagle and United Airlines have grounded aircraft to recheck jets.
Southwest cancellations earlier this month were to redo inspections that weren't done in the manner required by the federal rule. American Eagle's cancellations Friday were to recheck compliance with two directives.
United didn't have to cancel any flights as it rechecked equipment on seven jets for regular maintenance issues.
"Every airline will tell you they'll disrupt their service in the interest of safety," said David Castelveter, spokesman for the Air Transport Association, the major airlines' trade group.
Eighty-seven of American's cancellations occurred at Dallas/Fort Worth International Airport.
As of early evening, the carrier also had canceled 70 flights at Chicago O'Hare International Airport -- 31 percent of Wednesday's schedule.
Passengers left waiting
The cancellations give passengers another reason to be unhappy with the airlines. Bill O'Brien, a business traveler from Boston who was at D/FW Airport, said his flight was canceled without explanation.
"Delays are a fact of life when you fly as much as I do," said Mr. O'Brien, a sales director for an engineering services company who flies every week. "I'll live with it, but I also value my time."
American and Southwest didn't rule out more disruptions during the federal audit of their safety programs. FAA field inspectors have until Friday to check 118 carriers' programs for compliance with 10 airworthiness directives.
A Delta spokesman said the carrier decided Wednesday to voluntarily recheck its fleet of MD-80s and MD-90s to ensure compliance with the directive.
Anthony Black, a spokesman there, said the airline has 133 McDonnell Douglas jets and might cancel flights over the coming days to complete the inspections and perform any needed modifications.
The work involves protective sheaths that are wrapped around a 6-foot bundle of wires. The wires connect a hydraulic pump in a landing-wheel well to the rest of the plane.
The bundles are supposed to be tied together every inch to ensure that the sheath remains in place. In some cases, American found ties that were spaced farther apart -- including up to 1.5 inches.
A September 2006 airworthiness directive, based on a Boeing Co. service bulletin, required airlines to inspect planes within 18 months and make any corrections.
Wires that weren't properly secured could chafe or fail, causing a short that could affect power or trigger a fire close to the fuel tanks, according to the airworthiness directive.
An American spokesman said its inspections found no evidence of chafing or rubbing. But the airline found about 80 jets that needed modifications, American spokesman Tim Wagner said. Twenty jets were repaired and returned to service by Wednesday afternoon, he said.
The FAA has sent some inspectors from its office overseeing American Eagle to help complete the audit of American by Friday, FAA officials said. The work is being done in Tulsa, where American performs its heavy maintenance.
"If they need more time and there are issues, we would rather have those issues be addressed thoroughly," said Lynn Tierney, the FAA's assistant administrator for communications.
The FAA scrutiny was touched off by a congressional investigation, managed by Rep. James Oberstar of Minnesota, which found that Southwest Airlines operated 46 jets that missed federally required inspections for fuselage cracks.
Mr. Oberstar, chairman of the House Transportation and Infrastructure Committee, plans to hold an April 3 hearing to examine what he called lapses in FAA oversight. Two Senate subcommittees also plan hearings in April.
The FAA's initial audit will be followed by a check of a much larger sample of airworthiness directives. The deadline for that effort is June 30.
That campaign could detect more problems with the controls that airlines have established to ensure compliance with the directives, experts said. That's because many airlines may incorporate an inspection into a maintenance plan but fail to properly document the work as an airworthiness directive.
In addition, some directives require inspections to be repeated. With airline maintenance occurring in different places across the country, the possibility exists that only part of the work may have been done, experts said.
"It's a substantial piece of work," Mr. Goglia said. "You could very easily miss something, or you could accomplish the work and miss the sign-off."