Investigators of the loss of an Air France Airbus
A330-200 in the sea near Brazil on 1 June have cited incorrect
speed readings and electronic failures as they move closer to
understanding the crash, according toThe Times today.
Earlier this week, Computer Weekly highlighted
two fatal air accidents more than decade ago in which
conflicting speed readings from onboard systems and blocked
Pitot-static system sensors confused pilots in the final minutes of
flight.
Investigators of the loss of the Air France Airbus, Flight 447,
have suggested there might have been a problem with the aircraft's
Pitot sensors.
The Pitot-static system feeds information on air speed to the
onboard computers which control the pilot's displays. Shortly
before two Boeing 757 passenger jets crashed into the sea in 1996,
the onboard systems were telling pilots they were flying too fast
and too slow.
On an Airbus, the final say in extreme circumstances is usually
left to the onboard systems, not the pilot. If the systems on
Flight 447 received conflicting information on the aircraft's
airspeed, it is unclear how they would have reacted or whether they
or the pilots would have been left in control.
The loss of Flight 447, which claimed the lives of 228 people on
board, may never be fully explained unless a French nuclear
submarine is successful in recovering the black boxes, the flight
data and cockpit voice recorders.
Paul-Louis Arslanian, chief of the French accident investigation
bureau, said that it was too early to pronounce on the events that
led the Airbus A330 to crash into the Atlantic, though he added: "I
think we may be getting closer to our goal."
Arslanian confirmed that incoherent speed readings were reported
first in a series of alerts that the stricken aircraft transmitted
automatically to Paris during its final four minutes. The other
alerts "appeared to be linked to this loss of validity of speed
information". The faulty speed data affected other systems that
relied on them, he said.
French authorities have not commented on a
report that, after a flood of error messages, display screens
went blank and the pilots were unable to control speed, height or
direction.
Air France Airbus crash - its last few minutes?