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Addendum 8th June
MY LATEST VIEW OF THE CAUSES OF THE CRASH.
It now seems that Air France has admitted that a later design of Air
Speed "sensors," more resistant to icing were not fitted to the crash aircraft, in
spite of being available for 2 years. If the pitot static system that supplies air pressure data to the speed
indicators, among others, were to be partially or completely blocked by ice, then the differing and false
readings apparently experienced by the crew are explained.
At high altitude (the maximum possible for the aircraft at the time) there
is a smaller margin between a safe flying speed and an aerodynamic stall - a
condition in which the aircraft effectively stops flying - and this would be
especially critical in turbulence.
Addendum 1200hrs 2nd June 2009-06-02
For those interested in understanding the complex nature of the possible weather effect on this flight I suggest a look at
www.weathergraphics.com and the article by Tim Vasquez. It is an excellent informative piece that almost certainly shows the direction investigators will be looking in.
It now seems that there were multiple electrical failures automatically reported to Air France. These could either be the result of the airframe failure or the cause of it. The Airbus is a highly automated electronic aircraft and total electrical failure would present the crew with a challenging problem in smooth conditions. In serious turbulence, the risk of loss of control would be high, as the aircraft controls are electrically (computer) powered.
1st June, 2009
n Air France Airbus A330–200 has vanished whilst en route from Rio to Paris. Air France report that an automated message was sent by the aircraft notifying the company of an Electrical Short and also a Pressurization problem. Apart from stating that they consider the aircraft lost they have not elaborated on the reasons.
There is much discussion in the media of lightning strikes. These are very unlikely indeed to be at the root of the problem.
The aircraft was near the Inter-Tropical Convergence Zone, which generates huge, violent thunderstorms at certain times of the year. The weather was severe at the time the Airbus would have been in the area.
Only speculation is possible at present but the fact that no radio transmission has been received from the crew indicates a sudden catastrophic event. It is understood from Air France that the plane was experiencing bad turbulence.
Severe turbulence could theoretically cause the loss of control of an airliner with serious consequences, such as the in-flight break up of the plane.
This is only one of several possibilities but a likely cause if the turbulence was as severe as the satellite images of the area suggest. It is impossible to know if the aircraft’s weather radar was functioning but hard to imagine a crew flying into a storm cell if it was. However it would be very easy indeed if it was not.
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