Following a test flight: Hot trail in the SR
Thursday there was once more smoke on board of a
Swissair MD-11 - but this time it was allowed by
experts to billow out on purpose: During of a test
flight lasting around six hours, with activated
on-board television cameras, the Canadian SR-111
investigators in California took comprehensive measurements
of air flow. They wanted to find out in this
way how the fire had spread aboard flight
SR111. Apparently the investigators are following
a hot trail.
and shattered aircon ducting
we flew an MD-11 to Long Beach, California on January
24," confirms Swissair spokesman Urs Peter
Naef. Before that the SR technicians had to
configure the plane especially. The Canadian
investigative authority TSB wanted to get a plane
that would be practically identical with the "Vaud"
that had crashed on September 2, 1998. In
particular, the controversial on-board entertainment
system IFEN had to be installed here too.
Since the US Federal Aeronautics Board (FAA) had
prohibited the IFEN, an exceptional authorization
was given for the test flight. The experts
apparently believe that they know where the fire
landing in long Beach, the Swissair pilots had to
take their leave; on the test flight, only experts
of TSB and Boeing were present. The Canadian
team, under the direction of SR-111 Investigation
Head Vic Gerden, also installed video cameras, in
and Mark Fetherolf lost daughter Tara, and
like many others, remain convinced that
the IFEN played a part.
to various measuring instruments, in the cockpit
and in the forward area of the cabin. On Thursday
the MD-11 took off for its roughly six-hour test
flight. High above the clouds the crash experts
simulated the spreading of smoke. "For
this we used artificial smoke, such as is used in
theaters for example," said TSB spokesman Jim
such an expensive test with artificial smoke and
video cameras? "We were thus able to
make the air flow in the forward part of the plane
visible," explained Harris. The TSB experts
wanted to find out how the devastating fire had
spread on board of flight SR111 because they apparently
have a theory on what the source of the fire had
been. The measurements of airflow could further
support this theory. During the flight the
IFEN system was connected to the main power supply
and the display screens were switched on.
At the same time, different temperature measurements
were also made.
specialists allow hundreds of cables to be scorched
fire, started by the IFEN, is still assumed to be
one of the possible causes of the SR 111 crash.
Swissair deactivated the IFEN in all of its planes
a few weeks after the crash. For safety reasons,
as was claimed at the time. In the meantime
it became clear that the on-board TV system which
consumed a huge amount of electrical energy would
patterns may disclose the part that arc-holed
oxygen lines played
again be used: In the meantime it was removed from
one half of all planes. The manufacturer of
the entertainment system, Interactive Flight Technologies
has long gone out of business and calls itself now
Global Technologies. According to its own
statements it has now gone into the Mexican casino
business, among other things.
meantime, tests with airplane cables continue in
Canadian laboratories. TSB specialists allow
hundreds of cables to scorch through on purpose
- sometimes in clean air, sometimes in soot and
smoke filled air. The crumbled insulation
material is then subjected to chemical analyses.
What the experts want to know above all is this:
Is it possible, based on chemical analysis, to isolate
those cables that have burned through in clean air?
If this is possible, the method can also be applied
to the scorched cable sections of the crashed MD-11
- it would thus be possible to prove the origin
of the catastrophic fire with a high degree of probability.
"The question," says TSB spokesman Harris,
"is to know which cables burned through first
and which were first damaged by the fire".
The investigative authority is silent on the results.
"We are moving into a new field of science",
says Harris. "The tests are very costly
and take much time".
IFEN costs Swissair
certification and installation of the on-board entertainment
system IFEN in the MD-11 airplanes of Swissair followed
a strange course. Although it is a branch
of Interactive Flight Technologies (IFT), an unknown
company in the field, it was certified and installed
in the record time of six months. IFT promised
to install the system free of charge in the Swissair
planes. Refinancing was expected to come through
the proceeds from video films and games of chance.
However the passengers underutilized the entertainment
system - IFT encountered financial difficulties
and the delivery of the remaining installations
was endangered. Because Swissair had previously
played up IFEN as the attraction that would bring
in passengers, it had to pick up the pieces.
The entire on-board entertainment system was purchased
for 46 million.