Originally Posted by
CONF iture
To note that Mr R.A. Davis has been at the head of the prestigious AAIB during 15 years, and not only "an aircraft accident consultant" as the Airbus Response likes to describe him.
I've got a lot of time for Ray Davis, and read that he did exemplary work trying to get to the bottom of BEA548 back in 1972 - which was no mean feat given the lack of survivors and lack of a CVR (In fact the recommendations made by his team were what eventually made CVRs mandatory in G-registered transport category aircraft).
Airbus wasn't knocking him, despite how you're trying to frame that statement. They were pointing out that he had been retired for several years before he took the case on. You can't bring a doctor back after an extended period of retirement without first familiarising them with the advances that have happened in their absence - so it goes with accident investigators.
Also, he was specialized in the Flight Recorders decrypting …
No, he wasn't. For a start, Flight Recorder data is not "encrypted", it is encoded. On the old analogue gear this was as a series of voltages and on the newer digital boxes as a serialised sequence of binary data.
Ray Davis was a brilliant investigator, but he didn't really understand how DFDRs differed from their older analogue counterparts, which led him to make several erroneous conclusions about the tapes, which are explained at length in the article Franzl posted.
Originally Posted by
RR_NDB
DW:
The corner they entered (ultimately in the trees) was only "painted" by the pilots? Or the designers "preprogrammed" (with the new concept, protected FBW plane) the corner?
Yes - only painted by the pilots. They diverged from an already shoddily-put together flight plan because they missed the turning point for the airfield, then elected to expedite the descent rather than turn around and start the approach again - letting the engines spool down completely in the process (fatal mistake no.1).
They made the decision to disable A/THR completely to proceed with the display. As PJ2 said, the narrow, short runway may have fooled them into believing they were higher than they were. This prevented any chance that the system could help them out of their predicament (fatal mistake no.2)
Would not be safer to allow a pilot to just exit the corner when absolutely necessary?
In this case, no. I've already said that if Alpha protection had not checked Asseline's attempts to pitch up that the aircraft would have stalled and more would have died.
Rigid programming (hard limits) is really necessary? The pilots really need this kind of "protection"?
Clearly - sometimes - yes. This isn't a criticism of pilots as a breed, just an honest acknowledgment that we all have bad days at the office.
Funny that an allegedly "conveniently buried" issue has already been brought up at least three times in the course of discussing AF447, an incident which bears no relation to AF296 in any way, shape or form on a technical or procedural level.