With Brazil calling a halt to the search for any further bodies and debris, speculation is now centring around other similar incidents, including two crashes that seem to have been caused by blocked Pitot Tubes influencing the planes on board computers to initiate manoeuvres that the pilots either struggled to overcome or fatally could not correct .
Being able to understand how fast a plane is flying you would think is fundamental to pilots who have to control the flight! Well it would appear that Air France seems not to have paid as much attention to the air speed sensors (the Pitot Tubes) as they should have.
Remember the Airbus that went into the trees – although this did not relate to Pitot Tubes – there was no mention of it in the crash report.
In two A330 (the same type of plane) related incidents the pilots reported sudden erratic movements initiated by the planes computers that eventually were overcome and both landed safely without injuries.
In two other related fatal incidents involving Pitot Tube blockages, a Birgenair 757-225 (Flight 301) crashed shortly after take off when a faulty Pitot tube fed false speed information into the planes computer systems and caused immense confusion for the pilots who did not really know how fast they were travelling, subsequently a fatal crash occurred.
In second similar incident with an Aeroperu flight 603– the ground maintenance engineers had taped over the Air Speed sensors to clean the aircraft and forgot to take them off – the plane despite valiant efforts from the flight deck crew, crashed – this link is to a transcript from the Cockpit Voice Recorder of the crews attempts to fix the problem, it makes chilling reading.
Air France are in the process of carrying out checks/replacements of its aircraft Pitot Tube, how far back they know about the problem is not clear, though this post seems to imply, 2008.
Whatever the reasons, it is something that all airlines need to look at this quickly and reassure us all that these devices (the Pitot Tubes) and any issues that they have are fixed. Sadly for the passengers of AF447, this possibly appears not to have been the case!
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