QF72 style ADIRU failure = nose up
The QF72 incident and the earlier QF71 could have been fresh in the minds of the AF447 crew. I recall that the QF72 ADIRU fail caused false warnings of over speed, stall, underspeed, AoA. The QF72 A330 was cruising at mid day in good weather and the erronous flight instrument readings and warnings were immediately obvious and corrected.
As noted by the BEA there were some significant differences between the computer fail of AF447 and QF72. However there was some overlap in symptoms.
The point is that ADIRU malfunction should have been a known issue to the AF crew and they presumably would have had corrective procedures. Unfortunately the ADIRU fail procedures were inappropriate/exacerbating to their true predicament of pitot icing. It would explain the counter-intuitive behaviour of the pilots apparently ignoring the flight instuments and stall warnings and pulling the nose up.
Last edited by xcitation; 3rd Jun 2011 at 22:50.