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AF447 wreckage found

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Old 27th May 2011, 13:05
  #501 (permalink)  
 
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This unfortunate tragedy is just one more instance that demonstrates we are all loosing the basics of flying, as a pilot group. If indeed, the basics were there in the first instance.

Modern aircraft, including the A380 are not uncrashable and never ever will be.

Ever heard of K.I.S.S??
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Old 27th May 2011, 13:06
  #502 (permalink)  
 
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Ex 9 PPL syllabus stalling and recovery, level wings, pitch down break the stall apply power climb away.....dont get smart
So proffessional working pilots on this forum must know the answers as to why anyone would be pulling back when the airplane is in a stall condition, if its a reflex reaction brought about by hours flying a computer then I'm NEVER getting on an Airbus again
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Old 27th May 2011, 13:07
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Hi there Whatsalizad, thanks for your reply. I suspected someone might take issue with my comments, and I have no problem with your reply. I've never flown a commercial airliner, but did fly in the military, and as you mentioned, Power + Attitude = Performance was king of my world.

Yes, the QA A380 incident was alarming / frightening, but they stuck to basics and got it right.

I agree that we don't know what indications the aircrew received, which is why I admitted that my comments might be jumping the gun. Apologies if they annoyed you.
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Old 27th May 2011, 13:10
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Originally Posted by Parsnip
Ex 9 PPL syllabus stalling and recovery, level wings, pitch down break the stall apply power climb away.....dont get smart
So proffessional working pilots on this forum must know the answers as to why anyone would be pulling back when the airplane is in a stall condition, if its a reflex reaction brought about by hours flying a computer then I'm NEVER getting on an Airbus again
An interesting exception to this might be a dark night, a lot of aural & visual distractions, working through checklist items, and just possibly your instrument(s) telling you that you are speeding up.
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Old 27th May 2011, 13:11
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Dear Parsnip, please enlighten me: in what way is today handling a boeing less akin to flying a computer (or not at all) than in an airbus case?????
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Old 27th May 2011, 13:12
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27 May 2011 briefing
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Old 27th May 2011, 13:13
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Aviation-interested SLF here with a few question:

So if I understand correctly the AP was disengaged - but do we know why?

Airspeed indicators malfunctioned but apparently only briefly - so why did that not change the law back when they came online again? Because they already stalled?

And is there no warning or indication to the crew that the law has changed?

And why is there in certain laws - if I understand correctly no stall warning - if it is something so essential?

And shouldn't a vertical airspeed have indicated the pilots that they are actually falling out of the sky and prevented them as long as they still had altitude from pulling back?

Thanks much
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Old 27th May 2011, 13:19
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So if I understand correctly the AP was disengaged - but do we know why?
because the speed sensors went crazy:

From 2 h 10 min 05 , the autopilot then auto-thrust disengaged and the PF said "I have the controls". The airplane began to roll to the right and the PF made a left nose-up input. The stall warning sounded twice in a row. The recorded parameters show a sharp fall from about 275 kt to 60 kt in the speed displayed on the left primary flight display (PFD), then a few moments
later in the speed displayed on the integrated standby instrument system (ISIS).
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Old 27th May 2011, 13:19
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hi there,

I be an uneducated SLF type,

Question: the report says that-
at 2:10:51 ..."
The trimmable
horizontal stabilizer (THS) passed from 3 to 13 degrees nose-up in about 1 minute and
remained in the latter position until the end of the flight."


at 2:12:02 ...
"Around fifteen seconds later, the PF made pitch-down inputs. In
the following moments, the angle of attack decreased, the speeds became valid again and the
stall warning sounded again."

Why did the indication of the THS NOT change in accordance with the pilot input???

Am I way off base here?? Confused???

cheers
Phil
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Old 27th May 2011, 13:20
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Parsnip, the actions you list are in the wrong order.

your first action in a convential aircraft is to move the stick centraly forward while applying full power at the same time, DO NOT TRY TO LEVEL THE WINGS FIRST, as you may induce a spin. Once you have unstalled the wings you can then level them.

Airbus have recently modified their stall recovery procedures to delay the application of power until the nose has been lowered to prevent problems with the pitch up effect of the engines.
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Old 27th May 2011, 13:20
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Maybe I am missing something but doesn't a pilot have a big horizon in front of him, on the PFD?

A 35 degree up pitch is kinda hard to miss.
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Old 27th May 2011, 13:25
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"Firstly, it must be said that conventional instrumentation is not adequate for flight in the vicinity of the stall; pitch attitude can be most misleading, airspeed and altitude and vertical speed are only component parts of the one parameter which is all important - incidence - and in isolation, and indeed in sensible combination, these individual parameters can be either misleading or nearly valueless. The only valuable parameter is incidence. This is what dictates the behaviour of the aeroplane and this is what needs to be presented to the pilot."
From: "Handling the Big Jets", page 124, D.P. Davies, Third Edition, Civil Aviation Authority, December 1971
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Old 27th May 2011, 13:27
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Out of curiosity, what happens with the pitch/power dynamic coupling outside of normal law? For instance, if power is advanced to exceed that required for level flight, outside of normal law, will the aircraft pitch up unless commanded otherwise by pilot or the autoflight system?

Secondly, would the stab trim movement be the FCS attempting to trim the aircraft to relieve the elevator load from the commanded nose-up attitude, in other words, everything was behaving as it should?
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Old 27th May 2011, 13:29
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Jet Jockey A4

My understanding from reading the report is that the AP was off for 4min 23secs which was until impact. Not too sure where you get your figures from.

Although I have no manuals infront of me, I thought you could operate in RVSM airspace as long as you have 2 primary altimeters, 1 altitude alerting system, 1 altitude reporting transponder and 1 automatic altitude control system. I don't take that to mean you have to have AP working. As long as FD's are on. I could confirm this later with a check of the MEL.
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Old 27th May 2011, 13:32
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Jet Jockey A4:

The autopilot wasn't off for 90 minutes, it disengaged aprox 4 minutes before the crash because of (suspected) pitot tubes freezing up, and resultant confliction of airspeed indications (causing the systems to revert to 'alternate law', or in English, over to the pilots). They weren't hand flying for fun!

You seem to be slightly unfamiliar with this case.

I agree with you on the training front, and when I flew I also had extensive training in stall recovery and UA recovery with a variety of parameters. So your comment 'I just don't get it' has total agreement from me, mate!
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Old 27th May 2011, 13:37
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Hi Phil,

If you only briefly give a pitch down input the trim will not change immediately. There is no indication in the BEA Note on how long this down input was given (most likely briefly).
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Old 27th May 2011, 13:41
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I would like a bit of clarification from those with more knowledge of correct procedures in a jet. I have limited single engine time and some limited unusual attitude training in a T-28. The single most fundamental aspect that was repeatedly drilled into my brain was unload the airframe.

If I recall correctly one of the root causes of the 737 crash way back (Pittsburgh?) was the PF's failure to take this fundamental step. I'm becoming more and more concerned at what appears to be a very low level airmanship displayed here....correct me if i'm mistaken...

My feeling is this goes directly back ot the discouragement of hand flying. When the instruments in front of you go south the only instrument left is the one your sitting on
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Old 27th May 2011, 13:43
  #518 (permalink)  
 
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Thanks Decurion.

Noted. Not enough detail in the report.

...and thats where the devil be!!.

The final report will prove interesting ....as this prelim ...leaves or raises more Q's then answers.

Like many here ...I just can't believe, a capable aircrew would not attempt to recover from what appears to be an obvious stall condition.

Phil
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Old 27th May 2011, 13:48
  #519 (permalink)  
 
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Could it be similar to China Airlines 006? The pilot fixated at one problem missed other severe issues at hand?
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Old 27th May 2011, 13:51
  #520 (permalink)  
 
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appears to be a very low level airmanship displayed here
"Airmanship" and "Commonsense" are merely the use of things learnt during training, education and practice to keep one safe in the air. One doesn't "pick up" good airmanship or flying commonsense other than by those three aspects (or osmosis over a very long time).
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