Despite hundreds of airline cancellations today, the Federal Aviation Administration and industry experts are pleased with the early results of a widespread airline audit.
Results of the first phase of the FAA's audit, intended to ensure that planes are safe to fly, show a "very high rate of compliance," according to FAA spokesperson Laura Brown.
"What's going on here is just a big double-check around the system to make sure that things are absolutely right," said William Voss, president of the Flight Safety Foundation.
Some travelers, however, are perhaps less satisfied. On Thursday, Delta and American Airlines canceled hundreds of flights to reinspect wiring on their MD-80 series aircraft.
On Thursday morning, Delta announced it expected to cancel about 275 flights to examine more than 100 of its planes. Delta said cancellations would affect 3 percent of the carrier's worldwide schedule.
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Delta hopes to have 70 percent of the inspections completed by Thursday night and to return to a normal schedule on Friday.
"Delta apologizes in advance for any inconvenience this may cause and is working to proactively contact and reaccomodate affected customers," the airline's Thursday statement said.
The statement also said Delta would add staffing at its largest hub, Hartsfield-Jackson Atlanta International Airport, to help accommodate the thousands of travelers whose plans were disrupted. Transportation Security Administration (TSA) said it is also "fully staffing" security checkpoints in the Atlanta and Dallas airports, as it would for a snow storm or severe weather.
Hundreds of Flights Grounded
Delta was just the latest airline to ground planes for reinspections in the midst of the sweeping FAA audit.
Delta's announcement came hours after American Airlines grounded more than 300 planes on Wednesday to carry out similar inspections on its fleet of MD-80 jetliners.
Today, American is also facing more than 140 additional cancellations, according to the airline. Dallas/Fort Worth International Airport and Chicago's O'Hare are feeling the brunt of those cancellations.
American is rotating its MD-80 aircraft back into service as soon as the planes are cleared. The airline said Thursday that 269 of its aircraft have already been inspected, modified if needed, and put back in service. Twenty one of its planes are still being modified as a result of the inspections.
A statement Wednesday from American said that during the audit, a team of American Airlines and FAA inspectors became concerned about "how a certain bundle of wires is secured to the MD-80 aircraft."
The safety directive issued by the FAA requires airlines to do an inspection to ensure wires are not chaffing or rubbing together against parts of the plane. In some cases, the requirement calls for airlines to place an added protective sleeve around the wires. The requirement was called for after reports of shorting on wires, attached to an auxiliary hydraulic pump, located in the wheel well in certain MD-80 series aircraft.
American is not concerned with whether the work was done, but rather how it was done. The airline is required to secure wiring at every inch, and the aircraft in question may have had the bundles secured every 1¼ or 1½ inches.
"All that's at issue in this entire debate is exactly how the repair was done -- was piece of tape put on correctly? Was the insulation the right distance from the connector?" Voss said.
The FAA said Delta's issue concerned the protective sleeve covering the wire bundle.
Southwest Incident Prompts Audits
The FAA is taking extra precautions on the heels of accusations that Southwest Airlines missed, or failed to document, airplane inspections. That prompted the FAA to announce it was proposing a $10.2 million fine against the carrier -- the largest fine ever imposed against a passenger airline.
Last week, the FAA announced the far-reaching audit to ensure all airlines — more than 100 of them — are complying with maintenance requirements.
John Nance, former pilot and ABC News aviation consultant, said on "Good Morning America" that reinspections are the right thing to do.
"What we're hearing is the system is working exactly as the system should," Nance said. "It's self-correcting. Twenty years ago, when Aloha lost the top of 737 to aging aircraft structural problems, we didn't know how to inspect older aircraft. Now we do. This is merely a correction to make sure as they ground safe airplanes, that they don't become unsafe over time."
The Air Transport Association has approximately 470 MD-80 series aircraft registered to their member airlines, the vast majority of which are operated by Delta and American. Alaska Airlines found its 10 MD-80 series planes to be in compliance with the safety directive after inspecting them last night, and is operating today according to schedule.
After completing its initial review Friday, FAA inspectors plan to follow up with a more extensive audit, scheduled for completion in late June.
Congress plans to further examine airline inspection issues next month.