Air carriers will be required to replace or find a new way to cover insulation used in 831 Boeing Co. airplanes in the United States because it fails to prevent fire from spreading, the Federal Aviation Administration said yesterday.
The requirement, which is expected to be in effect by year-end, could result in the removal of the material from 1,600 Boeing 727, 737, 747, 757 and 767 planes worldwide, as regulators in other nations follow suit. Airbus SAS aircraft do not have the same insulation problems, the FAA said.
The problem was discovered in 2002 by a Canadian airline during maintenance of a 767 aircraft. When the cabin walls were stripped down on the plane, it appeared that a small fire caused by wires had occurred and extinguished without the flight crew knowing about it. Commercial airplanes have insulation between the metal of the plane's skin and the cabin, much like the insulation in a home, to keep the cabin warm when flying at high altitudes and to reduce noise. The insulation is often intertwined with wires, pipes and ducts.
FAA officials tested the thin layers of Mylar materials that cover the thick insulation in Boeing planes to see if it met the agency's standards, and they failed, said John Hickey, director of FAA's aircraft certification service. "If exposed to a spark, it should not light on fire and allow [the fire] to spread," Hickey said. "It failed a sufficient amount of times."
Orcon Industries Corp. of Union City, Calif., manufactured the Mylar material between 1981 and 1988.
Boeing said it supported the FAA's move, and that it is developing a spray-on flame-retardant material that it hopes can be used on the insulation to meet the FAA's concerns. If approved, the spray could eliminate the 16,000 estimated hours of labor it would require to replace insulation on the 747s, said Liz Verdier, a Boeing spokeswoman.
The FAA has already banned some other insulation covers on 700 McDonnell Douglas planes after the crash of Swissair Flight 111, an MD-11 that crashed off the coast of Nova Scotia after an in-flight fire believed to have been caused by a wire.
Air carriers will have six years to comply with the requirement, which is expected to cost $330 million and be completed at the time of the aircraft's scheduled major maintenance overhaul.