opherben
RWA wrote,
"So why no reason for the 2008 A320 accident at Perpignan either, opherben? In the final report? "
You are right. It isn't a complete, professional document.
Great, opherben. We appear to be of one mind.
Man Flex
RWA,
I think you might be reading too much into the THS "sticking" theory. I reiterate that the pilot must apply sufficent and sustained movement on the sidestike for the THS to move.
Sorry we're disagreeing, Man Flex. We currently have only the sketchiest information about AF447 - but we have fairly full information about Perpignan. In both cases the THS went to 'full up' and stayed there, whatever the pilot did. The 'difference' is that the (full) report on Perpignan clearly says that the captain repeatedly pushed the stick forward all the way to the stop, and held it there - but the THS just stayed in the 'full up' notch........
Studi
At the end, it boils down to 4 things:
Agree that all those things are relevant, studi. But I would submit that there are at least three other relevant factors.
1. The (known to be sub-standard) Thales pitots. Just the AF447 guys' bad luck that, although these were already being replaced, Air France just hadn't got round to replacing those on their particular aeroplane.
2. The weather. Not just the icing, but probably turbulence as well. Can't have helped.
3. The instruments. The positive 'cascade' of ACARS messages shows that one instrument and 'system' after another was cutting out or in right through the crisis period. I think the most serious criticism one can levy at the BEA is that they didn't say much about that issue in their first report, and say absolutely
nothing about it in their recent 'note.' Most of the malfunctioning was probably linked to icing in the pitots and ports. But we'll maybe never know what information the pilots had (or didn't have) as to the aeroplane's attitude, speed, or even its altitude at various times during the crisis. Especially, I fear, if we rely on the BEA to inform us........
In particular, we more or less 'know' that the pilots didn't have any sort of 'natural horizon' to work with. And it's only too possible that, at times anyway, they didn't have an artificial one either........?