Posted at 10:34 a.m. PDT; Thursday, October 15, 1998
FAA urges airlines to replace insulation
NOT THIS SORT OF INSULATION. THEY MEAN THE THERMAL ACOUSTIC LINING BATTS (aka BLANKETS)
by Don Phillips
The Washington Post
WASHINGTON - The Federal Aviation Administration (FAA)
recommended yesterday that the insulation on almost all of the
world's 12,000 passenger jets be replaced as soon as possible,
because new tests are likely to find that it can catch fire when exposed to high heat.
Some aviation officials estimated the price tag for the switch could
total billions of dollars. The recommendation grew out of the
investigation of Swissair Flight 111, which crashed off the coast of
Nova Scotia last month. While the cause of the crash is not known,
there are indications that some of the wreckage had been subjected
to heat and possibly a fire. The pilots reported smoke in the cockpit
before the crash, and "heat-distressed" wreckage from the cockpit has been found.
The retrofit, which the FAA said it will likely make mandatory after
new flammability tests and specifications are developed in about six
months, affects almost all airliners manufactured by Boeing, Airbus
Industrie, McDonnell Douglas and Fokker. Officials said the
Lockheed L-1011 - about 200 of which are still flying - appears to
be the only jet manufactured with acceptable insulation. The
material under scrutiny is not wiring insulation but, rather, looks
similar to home insulation and is used for the same purposes: to minimize noise and
trap heat. The action is not expected to disrupt flight schedules, because it
would be performed during regular major maintenance periods.
Aviation-industry officials point out that insulation fires have been extremely rare.
FAA Administrator Jane Garvey said in an interview that the
agency does not consider the fire threat serious enough to issue an
"airworthiness directive" ordering immediate replacement, but the
FAA may change its position if further research proves the threat to
be greater than expected. For now, the agency, which had
previously certified the material as not flammable, recommends
replacement at "any reasonable maintenance opportunity."
The FAA has known about the potential flammability of jet
insulation for at least two years and, possibly, longer.
In 1996, the Civil Aviation Administration of China strongly
recommended new tests after a Chinese Eastern MD-11 fire in
Beijing in 1995. The Chinese agency told the FAA its own tests
found that the insulation burst into flames, but the FAA brushed this
off, because the tests conducted by the Chinese were not required
by the FAA. "While the tests you conducted are illustrative, they do
not invalidate the certification of the material," the FAA wrote.
In addition, Boeing has developed more stringent tests for its own
internal use, leading to the company's recommendation last year
that the metalized Mylar insulation - still in use on the Swissair
MD-11 - be removed from planes manufactured by McDonnell
Douglas, which Boeing acquired in 1997. The FAA technical
center in Atlantic City also issued a report in September 1997
declaring current testing methods inadequate.
Swissair crash was factor
But FAA headquarters did not consider the matter urgent until after
the crash of Swissair Flight 111. Investigators found pieces of
metalized Mylar in the wreckage, although no burned pieces have
been found. The first major portions of the wreckage were dredged
from the ocean floor only recently. Still, investigators are examining
whether these insulation blankets may have played a role in the crash.
Investigators found that metalized Mylar had been implicated in at
least three major aircraft fires, in China, Italy and Denmark.
Although the insulation blankets were not a source of ignition, they
erupted into roaring fires when subjected to electrical short circuits.
No one was killed in those fires.
Thomas McSweeny, the FAA's associate administrator for
regulation and certification, said further tests at the FAA's technical
center in Atlantic City proved that most other insulation used in
airliners also would almost certainly fail any new flammability tests.
The materials also did not do well in the tests developed by Boeing
and used by the Chinese, he said. This includes the foam used in
Airbus products and the metalized Tedlar used on Boeing planes, he said.
The `Q-Tip test'
Boeing's Tedlar insulation technically passed the company's test -
called a "Q-Tip test" because it involves dropping a burning swab
onto insulation samples - but full burn tests conducted at the FCC
center in Atlantic City showed Tedlar also would feed a fire under
the right circumstances. Airbus' insulation foam "does not perform
very well" in the swab test, he said.
McSweeny said the only clearly acceptable insulation at this point is
either Fiberglas or a material known as Curlon. Those two
products then are wrapped in a polyimide film, commonly known
by its DuPont trade name, Kapton.
McSweeny said the FAA will consider any airliner using those
types of insulation to be grandfathered in, if any new regulations are adopted.
Lockheed, by coincidence, used acceptable insulation when it built the tri-engine
L-1011 jet. Ron Hinderberger, Boeing's director of aviation-safety
investigations, said he does not consider the FAA's statement an
overreaction. He noted that Boeing already used more stringent
tests and added that aviation constantly evolves to produce better and safer
products. Hinderberger also said that Boeing agrees with the FAA's decision
not to issue an immediate order. He said Boeing has no record of
any passenger death related to an insulation-fed fire.
A spokesman for Airbus Industrie said the European consortium
could not comment on the FAA's stance, because it does not have
enough details. Likewise, the Air Transport Association, which
represents major airlines, said it could not comment. But an airline
executive who asked not to be named said the industry was
surprised by the action and found McSweeny's comments
confusing. "We find it very strange he's making definitive statements
like that when it's not clear he's tested all this material," the executive said.
What it could cost
The stakes are high for airlines. The FAA said it has not calculated
the cost to the airline industry to replace the insulation. But
manufacturing and airline sources said it would likely be more than
$1 billion and, perhaps, much more. Some experts estimated total
replacement could run as high as $3 million a plane, although
manufacturing sources said that figure may be inflated.
Jim Hall, chairman of the National Transportation Safety Board,
said he could not comment on the technical details of the FAA plan
until his staff receives a full briefing.