After reading Aviatrix's excellent summary of an Air Caraibe incident related to 'bad' air data and instrumentation malfunctions, I was shocked to discover the following information from a Boeing website:
Jun 14, 2009
During the past 10 years, more than 300 accidents and incidents have been reported as a result of erroneous flight deck information, including problems with pitot-static probes and air data computers. Several fatal accidents that involved erroneous flight instrument information and six incidents resulting from lost or erratic air data occurred in 1996 alone.
Some fatal and near fatal accidents have been tracked back to something as mundane as a strip of tape over a sensor port. The Air Caraibe incident involved severe and sudden icing in cruise flight, and may prove to have some common elements with Air France 447.
To a pilot who has become finely tuned and trained to flying by instruments, suddenly having to determine which pieces of conflicting information are right and wrong and how to respond is a huge challenge. During flight in turbulence at high altitude the margins for error can be very small (see previous posts about airspeed envelopes.) A wrong decision and control input can quickly put a jet airliner into a situation from which there is little chance of recovery.
Understanding the causes behind Air France 447's demise is extremely important - making it even more urgent that the 'black boxes' are found.