Faa To Order Insulation Replacement For 700 Planes
WASHINGTON - Insulation on nearly 700 commercial airplanes will have to be replaced within the next four years because it badly fails a flame-retardancy test about to be instituted, a senior Federal Aviation Administration official said today.
The proposed airworthiness directive, however, will not require the sweeping insulation replacement that the agency had discussed back in October, shortly after a Swissair plane crashed off Nova Scotia following a report of smoke in the cockpit.
FAA officials said today that the agency backed off a plan that would have ordered the replacement of insulation in nearly every U.S. commercial airplane because recent research showed that most existing insulation passes or only narrowly fails the new flame test.
Instead, the more limited order will apply to about 700 U.S. airplanes built by the former McDonnell Douglas, which is now owned by Boeing. They include the MD-80, MD-88, MD-90, DC-10 and the MD-11, which is the type of Swissair plane that crashed last September, killing 229.
Under the proposed order, airlines will have four years to replace all metalized mylar insulation with products that pass the new test. The order will take effect after a 45-day comment period and time for revisions.
The carriers primarily affected are American Airlines, Continental, Delta and TWA. Alaska Airlines, FedEx, Reno Air and US Airways also fly planes covered by the order.
In 1997, McDonnell Douglas told airlines they should consider replacing metalized mylar insulation because it might be flammable. Insulation is used in airplanes to keep passengers warm and to dampen the noise of rushing air and engines. It is often installed in sheets, much like attic insulation.
Since the Swissair crash, experiments the FAA has conducted in an effort to create a new test and flame retardancy standard for aircraft insulation have confirmed the concerns about metalized mylar aired by both McDonnell Douglas and Boeing.
"It doesn't just fail the test; it fails it by a wide margin," said Beth Erickson, director of the FAA's aircraft-certification service. "If there is a low-level ignition source, like an (electrical) arc, it will catch on fire."
Asked whether the agency had caved in to pressure from the airlines, which balked at the expense of a wholesale replacement, Erickson said: "No, the science helped drive us to the decisions that we were making."
She said another concern was that replacing insulation that has only a minor safety threat might create problems, since insulation is often threaded around wires and other potential ignition sources.
The cause of the Swissair crash remains under investigation. The pilots of the New York-to-Geneva flight reported smoke in the cockpit 16 minutes before their MD-11 crashed into the ocean.
The Swissair plane was insulated with metalized mylar, generating questions about whether that may have helped spread an electrical fire.
Existing insulation is tested over an open flame or by throwing a lighted cotton swab on it to see if it will burn. Under the new test, known by some in the aviation community as the "Garvey Test" because FAA Administrator Jane Garvey vowed to create a new test standard, insulation is exposed to an open flame and an overhead heat source. Any resulting fire cannot spread more than two inches from the open flame and must extinguish itself when the flame is removed.
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