Monday, February 15, 1999

Thursday, February 4, 1999

Air directives fall short, U.S. agency member says

OTTAWA (CP) - Airworthiness directives issued by the U.S.
Federal Aviation Administration are falling short of their marks,
says an agency member who sees the same problems being
repeated across the industry.

A directive last Thursday called for a one-time inspection for
chafed or otherwise damaged wires in MD-11 planes like
Swissair's Flight 111.

But a one-time inspection is not enough, says Ed Block,
recently appointed to an FAA task force on electrical wiring.

"If the issue is repeated rubbing or chafing or shorting, it should
be a periodic inspection," he said in an interview from
Pennsylvania.

He also said the wiring directives did not specify what insulation
was suspect.

None identified the type of insulation involved - Kapton - and
therefore they didn't alert operators of other aircraft types using
the same electrics.

The directive last Thursday came after Canadian and U.S.
investigators found evidence of wire insulation damage in more
than a dozen of the McDonnell-Douglas planes, including some
belonging to Swissair.

Flight 111's pilot reported cockpit smoke before the MD-11
plummeted into the ocean. Investigators have focused much of
their attention on the plane's electrical and entertainment
systems.

Thursday, February 11, 1999

Fire extinguishers spent

But investigators don't know if discharge occurred before or after the crash

By Stephen Thorne -- The Canadian Press

OTTAWA - Three fire extinguishers recovered from the crash
of Swissair Flight 111 were spent or partly spent, but the chief
investigator says it isn't known if their discharge happened
before or because of the crash.

Canadians looking into the accident that killed 229 people Sept.
2 off Peggy's Cove have seven of eight hand-held extinguishers
that were on the MD-11 jet when it left New York, Vic Gerden
said in an interview.

Four fully charged

"We know that four of them were still fully charged and three
were not," he said. "But they were badly damaged and could
have been discharged on impact."

Investigators are still studying five halon and two dry chemical
extinguishers in part to determine where they were in the plane.

Pilots first detected cockpit smoke several minutes before they
radioed the problem to air traffic control in Moncton, N.B., at
10:14 p.m.

Almost 11 minutes later, as they headed away from Halifax
airport to dump fuel, pilot Urs Zimmermann declared an
emergency and said he must land immediately.

Electrical systems started failing during the next 90 seconds,
then contact was lost with the plane and black-box recordings
ceased.

The three-engined jet crashed about six minutes later, with its
No. 2 engine stopped.

In a sweeping 90-minute interview, Gerden, an engineer and air
transport pilot, suggested something precipitous happened as
Zimmermann worked his way through the plane's emergency
checklist.

Anomalies on the digital flight recorder indicate systems started
going down one by one. Within 90 seconds, all electrical power
was lost.

Yet the plane's air-driven generator - a windmill-like device that
can be deployed outside the fuselage, using the jet's slipstream
to provide emergency electricity or hydraulics - was never used,
Gerden said.

87 per cent recovered

Much of the investigation involves an elimination process,
layering tidbits of information gleaned from the 87 per cent of
aircraft recovered.

Here's some of what investigators know:

Memory chips, which investigators had hoped would yield
some information that went unrecorded by the black box, have
proven in many cases to be too damaged.

Toxicology tests on flight crew remains found no hydrogen
cyanide from burning polyvinyl chloride plastic, nor did they
find evidence of carbon monoxide.

The types of remains recovered were "not conducive" to
finding the latter, Gerden said.

Investigators don't have enough of the oxygen lines to
determine whether they played a role in the apparent fire
aboard Flight 111.

They look similar to some hydraulic lines and identifying them
requires time-consuming tests.

The smoke switch, a dial used to shut down and repower each
of the plane's three main electrical systems to help isolate a
smoke source, has not been found, so investigators don't know
how far into a check list Zimmermann was when he made his
request for an immediate landing. The question is key since
repowering wires encased in damaged Kapton insulation can be
fatal.

Molten aluminum found behind the cockpit door - less than
found in a typical key - might have come from a support
bracket near an emergency light battery.

The bracket would melt at 650 degrees C, but evidence so far
indicates the plane's outer skin was intact.

The throttles were not recovered. However, other evidence
indicates the settings were normal.

Thousands of pieces

The plane crashed at a steep angle and high speed, which
accounts for the "hundreds of thousands" of small pieces
investigators have boxed in 640 crates outside Dartmouth, said
Gerden.

Determining the "geometry of impact" may depend on
calculations derived from the angles at which certain debris is bent.

Said Gerden: "It's certainly one of the more challenging
investigations that's faced us - and others, I suspect. It will take
some time to do it."