August 4, 2005
Speed, brakes, steering in Toronto crash probe
By Janet Guttsman
TORONTO (Reuters) - The Air France jet that crashed in
Toronto this week was traveling at almost 100 mph (160 km/h) as
it careened off the end of the runway during a storm and
toppled into a ravine, investigators said on Thursday.
among items being examined in an investigation that could take
months. But it was unlikely a single factor caused the fiery
accident Tuesday that was survived by all 309 people aboard.
"We are examining the steering and the brake units," said
Real Levasseur, lead investigator with Canada's Transportation
Safety Board. "It's slow, painful work."
The wide-bodied jet sped off the runway and burst into
flames. A few dozen received minor injuries, including broken
bones, incurred as they left the aircraft through escape
hatches or down emergency chutes.
Levasseur said the crew reported no problems as the plane
approached Toronto's Pearson International Airport. The
aircraft probably touched down at about 160 mph (260 km/h), but
had slowed to only 95 mph (150 km/h) by the time it ran off the
end of the runway.
He said thrust reversers, used to brake the plane on
landing, had deployed on three of the four engines, but the
fourth engine was too badly damaged for investigators to say at
this stage if the reverser had engaged or not.
But he said the reversers account for only 5 percent to 10
percent of a plane's braking power at landing, so even a
failure should not have by itself been a major problem.
"Causes to aircraft accidents are always multiple. It's
never a single cause," said Levasseur, who is leading a team of
35 from Canada and 17 from elsewhere, including the U.S.
National Transportation and Safety Board.
INTERVIEWS AND BLACK BOX
Investigators planned to interview crew members Thursday
and are examining the plane's black box flight recorders, which
could contain between 200 and 4,000 pieces of information.
The plane, which had been en route from Paris to Toronto,
was reduced to a burned-out carcass after the accident, with
pieces of wing and a gleaming, white nose visible among charred
and mangled wreckage. The team will remove items like wheels
and brake fittings for closer investigation.
Much attention has focused on weather conditions at the
airport, which is Canada's biggest and busiest.
The airport was under a red alert as the plane landed,
which means there is a danger of lightning and thunder. Planes
can land but ground activity, like the unloading of passengers,
"If it turns out that weather conditions were a determining
factor, we will make whatever decisions are necessary in terms
of safety measures that may be needed," Levasseur said.
Investigators will also look at whether a wet runway could
have caused aquaplaning, or if a sudden tail wind could have
blown the plane toward the end of the runway.
Air France said the Airbus plane had 28,418 flight hours in
more than 3,700 flights and had joined its fleet in September
1999 -- making it a relative newcomer compared with the large
number of far older planes still flying. It was last serviced
on July 5.
The A340-300 has a range of more than 7,000 miles, which
makes it popular with more than two dozen carriers for
long-haul flights. It was the first in-flight crash involving
an A340, Canadian officials said.