Aviation Experts Puzzled Over Events Leading To Greek
Tragedy
Aviation experts in the US say they're puzzled over the crash of
a Helios Airways 737-300 near Athens Sunday. Specifically, they're
wondering how something less than a catastrophic depressurization
incident could have incapacitated the flight crew, but apparently
not everyone aboard the aircraft.
"It's odd," ALPA Executrive Air Safety Chairman Terry McVenes
told the Associated Press. "It's a very rare event to even have a
pressurization problem, and in general crews are very well trained
to deal with it."
McVenes said, if the aircraft lost cabin pressure, then the
flight crew didn't react according to that training. The aircraft
didn't immediately descend to an altitude where pressurization
wasn't required. It didn't make for the nearest airport -- but
continued flying as a "renegade" aircraft for well over an
hour.
When Greek F-16s intercepted the Helios 737, they were able to
see inside the cockpit, where the copilot was slumped over the
controls. The pilot was not visible to the fighter pilots. Oxygen
masks were seen dangling from the cockpit ceiling.
Further, there were two people moving about in the cockpit,
apparently trying to take control of the doomed 737. Although
post-crash search teams reported finding bodies that were "frozen
solid," at least 20 of the 121 people on board the flight were
alive when it impacted the ground.
If there had been a sudden depressurization at
34,000 feet, the windows would have iced over, as was the case when
Payne Stewart's Learjet crashed in 1999.
There were no obvious cabin breaches -- no holes in the aircraft
visible to the F-16 pilots, no windows blown out. That appears to
be a further indication that the depressurization wasn't sudden in
nature and didn't kill all on board.
And yet...
"[The copilot] couldn't
have been unconscious for a small decompression at 34,000 feet,"
Paul Czyz, professor emeritus of aerospace engineering at St. Louis
University told the AP. "Something's amiss. Even if the
pressurization system was failing, it doesn't fail instantaneously.
Even if it goes fast, you can seal the cabin, you've got all the
oxygen in the cabin to breathe, you've got the masks and you've got
plenty of time to get to 12,000 feet."
Former NTSB Chairman Jim Hall told the wire service, "The
accident did not have to occur. It has to be either a training
issue or an equipment issue."