@Old Carthusian:
Originally Posted by Old Carthusian
Originally Posted by rudderrudderrat
You'll find that every Boeing & Lockheed has a dedicated stall warning stick shaker.
Which can and has been ignored by pilots. It is important to remember that this is not an accident related to the aircraft configuration. It is an accident related to aircrew behaviour.
All very true, sir.
However, in the spirit of
trying to close as many holes in the proverbial swiss cheese as possible, I see no harm in at least considering whether stall warnings via a different cognitive route (i.e. non-verbal, non-text) might be helpful - although as you say, also not perfect.
In the case of AF447, the question in my mind is whether the stall warnings were (a) not heard (e.g. cognitive overload or similar) - perhaps stick shaker
would help here; (b) heard but not
believed (due to multiple
apparent problems with the aircraft behavior, leading especially the PF to ignore all warnings?) - stick shaker might be ignored in this case too!; (c) some other reason.
Personally, I fear that the answer is (b) but of course, I don't know. I think that
rudderrudderrat has put forward a very good case for auditory overload (also
Ian W) - I know that when I'm trying to speak to someone, I do tune-out all extraneous sounds; I can't tune out only selected sounds unless one sound is
especially loud. So perhaps the answer is (a), and for that reason shouldn't a stick shaker be considered, for those occasions when it
would help?
@mm43:
Originally Posted by mm43
AoA Vane #1 was having a 'rest' well before the AP disconnect.
I mentioned this a few weeks back, and
sensor_validation kindly pointed out a very plausible potential cause (link below) unrelated to ice (I don't know if that's what you were suggesting?):
http://www.pprune.org/tech-log/45687...ml#post6628318
@TJHarwood:
Originally Posted by TJHarwood
I respectfully submit that the very length of these various threads on AF447 in itself indicates a widespread enough fear in many quarters that other high altitude UAS events on various aircraft could all too easily end equally fatally (under circumstances identical or very similar to AF447).......
I also thought you were right. I was only replying to (what I believe)
Clandestino was saying, where he seemed to be saying that if 32 other crews could manage clogged pitots successfully, then AF447 was the exception. The reason I posted was that this assertion seemed to conflict with the data & analysis presented in the 2nd Interim BEA Report (which I found very interesting, as it touches on some aspects of my professional life).
If I misinterpreted what
Clandestino was saying, and if everyone agrees that
some of the other 32 incidents were also (or could, in other circumstances like in turbulance, at night, at FL350, have developed into) "close shaves", then I happily withdraw from the conversation for the moment.
