Friday, October 16, 1998 - Page updated at 12:00 AM

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Airlines Back Faa On Call To Replace Insulation On Jets -- Upgrade Fleets Over Time, Industry Says

The Washington Post

WASHINGTON -The airline industry said yesterday it agrees with the Federal Aviation Administration that new burn tests on aircraft insulation indicate most of the material must be replaced in an orderly process over several years.

Carol Hallett, president of the Air Transport Association, said the insulation is not an immediate safety issue and "we do not know of a single injury or fatality" ever caused by burning insulation. She said the FAA action does not stem from a defect but is "a better way of keeping our skies safe."

The effectiveness of most types of insulation - used throughout aircraft fuselages to muffle sound and protect passengers from heat and cold - has been questioned for at least two years by some aviation officials. Action did not come, however, until after the crash of Swissair Flight 111 on Sept. 2 near Halifax, Nova Scotia, which killed 229 people.

A cause for the crash has not been determined. But the Swissair McDonnell Douglas MD-11 jet was known to have some metalized Mylar insulation, which McDonnell Douglas and later Boeing recommended be replaced because of possible flammability problems.

The FAA informed airlines and manufacturers Wednesday that new burn tests showed that not only metalized Mylar but also almost all other forms of aircraft insulation could catch fire when exposed to high heat. The agency recommended that all current insulation be replaced at heavy maintenance periods, and it said it would develop new tests and likely issue mandatory rules in about six months.

Officials of the ATA, which represents all major U.S. airlines, asked for a technical meeting with FAA officials yesterday morning to get more details. Afterward, they said the FAA analysis seems solid.

"It's pretty hard not to agree with the FAA's logic that it must be replaced eventually," said Jack Ryan, the ATA's vice president for operations. Swissair, while technically not bound by U.S. regulations, also pledged to honor any order by U.S. authorities.

Hallett and Ryan stressed, however, that no planes would be grounded and no passengers would be inconvenienced because of FAA assurances that the work could be done at regular maintenance intervals. Hallett said an estimated 4,724 aircraft represented by the ATA are affected, out of about 12,000 worldwide. ATA members operate 60 of the world's roughly 200 Lockheed L-1011 jets, the only aircraft with clearly acceptable insulation.

The ATA stressed that the industry still does not know how quickly manufacturers can supply the acceptable insulation-fiberglass or a material known as Curlon wrapped in a polyimide film such as Kapton. Several manufacturers now make at least some polyimide-wrapped fiberglass. But Orcon, a Union City, Calif. company that made Curlon, no longer produces it, and Hallett said it is uncertain how long it would take the company to resume production.

Also left unanswered is whether other forms of insulation might be found that could pass the planned new tests. Airlines and the FAA also do not know how much it will cost to replace the insulation, though some estimates run higher than $1 billion.

The insulation issue has illuminated the world of product testing, which is a vital part of all manufacturing - particularly aviation - but often murky to the general public.

At issue is an insulation flammability standard that was set in 1975, and which top officials at the FAA began revisiting only recently.

The previous FAA standard for flammability involved only one test involving three samples of the type of insulation being reviewed. All insulation is composed of a thick layer of insulating material, such as fiberglass, which is covered by a thin film. The thin film is usually the root of any flammability problem.

The insulation is held in a vertical position in a standard burn box. A flame is then applied to the sample for 12 seconds and removed. To pass the test, any flame must extinguish itself within 15 seconds, and the length of burn up the sample must not exceed eight inches.

Although some questions were raised about the adequacy of the testing over the years, no one appears to have seriously challenged it for more than two decades. In retrospect, one industry official said privately, "a piece of firewood would pass that test."

Copyright (c) 1998 Seattle Times Company, All Rights Reserved.


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