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AF447 wreckage found

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AF447 wreckage found

Old 28th May 2011, 12:05
  #681 (permalink)  
 
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C.N. you sure got that right!
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Old 28th May 2011, 12:09
  #682 (permalink)  
 
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Power PLUS attitude = Performance

On my A330-300, set 2.5 nose up and 78% N1 for S + L flight at most weights.

You should also know what sound levels to expect in the cockpit from the Airspeed in cruise.

If you think that you might indeed be too slow then set CLB detent and lower the nose to 0, wait till the noise level returns to near normal then set it back to 2.5 and 78%.

All the while checking the GPS groudspeed from the FM to use as a gross error check whilst flying the Aircraft as smoothly as possible until I exit the area and hopefully all returns to normal.

Anytime I approach an area of suspect wx I cannot avoid I try to do 4 things:
1/ sit the cabin crew down, 2/ check the current GS and listen to the noise
levels, 3/ note the current attitude and N1 to achieve current speed and finally 4/ brief the FO on all of the above just incase all hell breaks loose.

I've done this for the last 10 years or so. Why did I consciously do this? Because our Airline has had it's share of Iced up Pitot static systems causing overspeed and stall warnings On the 744, 777 and A330 types where the crew did what I suggest above ( ie: fly the damn plane on Attitude and N1 ) to a successful outcome.

That sounds like the missing procedure, and hopefully one that will be thought hereafter!
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Old 28th May 2011, 12:10
  #683 (permalink)  
 
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As I said above this scenario is not new unfortunately. There are now quite a few documented cases around the world with Boeing and Airbus operators. Enough incidents that Boeing and Airbus have for some time now included checklists in their QRH's and also recommended all crew be exposed to it in the Sim during their recurrent training cycles.

Thread drift.........This maybe more proof that employing low time inexperienced crews is just plain dumb, Airline managers trying to save money please take note.

There is no substitute for experience, full stop end of story
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Old 28th May 2011, 12:11
  #684 (permalink)  
 
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As expected reading the last few pages, the usual crowd of perfect pilots comes on to disparage those pilots who were imperfect, the only difference between the perfect pilots and the rest are that the perfect pilots strut around here like a bunch of cockerels, the imperfect pilots are out there facing the real world scenarios...

Anyway that aside, to me what was said and the actions of the PF, with no real dissent from either of the other two imperfect pilots who were there, indicate that something either in the instrumentation or the plane's response to inputs was diametrically opposed to what the crew expected to see or experience. Unless you perfect pilots believe that all three highly trained pilots on the flight deck on that dark night were so grossly incompetent that they could not follow basic airmanship as a matter of course, then there must be some factor(s) that the data recorders have not been able to provide and which may never be known.

As for the dogmatic statements by some perfect pilots above that the crew shouldn't have flown into the storm or flew a perfectly serviceable aircraft into the sea, your comments are beneath contempt, not only for their insensitivity but also for their gross simplification of a situation that you in reality know absolutely nothing about.
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Old 28th May 2011, 12:12
  #685 (permalink)  
 
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Could someone explain to me why there was no distress call in 3 minutes ?
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Old 28th May 2011, 12:13
  #686 (permalink)  
 
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An interesting read, forget technology and stall recovery techniques, I believe beyond the system failure the cause to this accident runs deeper. Whenever we go into a degraded mode the assumption made is that the pilots have the skill recency to deal with the problem. My view is that modern EFIS systems have led to pilots forgeting to scan their instruments. Their focus is on the MCP/FCU and the FMAs not the attitude or performance instruments. Even on the approach rather than looking at the speed many pilots just trust the autothrust to maintain it.

Retaining basic instrument skills is easy even with a low tech PC flight simulator but few people do it unless they are going for an interview. Until this issue is addressed, events such as this will continue albeit infrequently.

Power + Attitude does equal performance but first you have to look at the instruments.
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Old 28th May 2011, 12:19
  #687 (permalink)  
 
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No AoA indication?

The key question here is - 'did the pilots have enough information to realise they were stalled, pitched up, throttles closed, and recover'?

I am surprised that in all this discussion (including that of the thoughtful Shadow) putting forward idea that the pilots didn't know what the AoA is, nobody has mentioned the backup AI (about 6 inches to the right of the captains MFD)? Was it really not noticed by 3 experienced pilots that the there was a huge difference between PFD and backup AI, which would have indicated a big pitch up, and yes (as mentioned by another poster) - no noise in the flight deck? Isn't this why the backup instruments are there? Or am I missing something (only a humble PPL/IR)?

Obviously there's a fundamental difference between AoA and attitude (ie the vertical speed of the air) but I am trying to think of a conceivable Wx scenario that would deliver up to 40 degrees pitch up on the AI with closed throttles for an extended period, and not indicate a stall.

nitpicker330 - yes! Power+Attitude=Performance. They had power - they had a backup AI. They also had, I presume, an 'alternate air' feed (like my Mooney!) which would have got the altimeters working again, at least the backup ... There was a lack of training and/or airmanship here, probably a huge dollop of denial (surely EVERYTHING can't have gone wrong!), though it looks as if Airbus need to seriously look at some kind of mechanism to warn the pilots if the computer lacks confidence in it's view of the world (due to inconsistent inputs) and advise the pilots to check the backup instruments.

We have all been trained and examined in the effects of icing in the instrumentation. It seems amazing that 3 experienced pilots wouldn't have guessed something was up, especially IR onwards.

All in all, I am concerned that it can't be as portayed as those 3 guys should have figured out what was happening.
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Old 28th May 2011, 12:21
  #688 (permalink)  
 
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Retaining basic instrument skills is easy even with a low tech PC flight simulator but few people do it unless they are going for an interview. Until this issue is addressed, events such as this will continue albeit infrequently.
Never a truer word...
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Old 28th May 2011, 12:28
  #689 (permalink)  
 
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Capt was away from the cockpit resting!

Whenever flying as multiple/augmented crew, my company schedules 2 captains & 1 F/O (this was gotten forcefully accepted by our pilots' association and the captains). So at all times you have 1 capt on the flight deck and somestimes 2 capts whilst the F/O is on a break. In the relaxed cockpit crew scheduling regime at AF and possibly other reputable carriers as well they put 2 F/Os in a 3 member set. Considering enroute WX forecasts and/or actual WX returns the Capt on AF 447 should have retained his seat and reclined it for rest. I can't understand how any responsible capt would prefer his allotted rest over safety of operation especially if that rest meant being away from the flight deck. Sheer negligence I'd say. AF and other companies that allow crew rest periods need to urgently review their scheduling policy and advise their crew to exercise sound judgement and discretion for rest periods considering segments of bad enroute WX. I always thought that one takes adequate rest prior to assuming duty and layover time is best spent and meant to arrive fresh for duty. I hope and am sure that the final report will adequately address the question of this capt, his rest break, and absence from the cockpit.
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Old 28th May 2011, 12:28
  #690 (permalink)  
 
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Yes but it's not only the Pilots that need to do this.
The onus should also be on the operators to 1/ recruit the appropriately experienced crews and 2/ ensure they retain their Piloting skills through targeted appropriate training packages throughout their career insisting they maintain basic instrument skills and know how to fly raw data ( this is not encouraged at all, indeed it is frowned apron now days )
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Old 28th May 2011, 12:30
  #691 (permalink)  
 
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I have a question:

the news media has described the 3 minute drop into the ocean as having been 'horrifying' for the passengers. However, if indeed the pilots didn't even realize that the plane was stalled and was descending so quickly, could it be that the passengers were completely unaware of anything being wrong during their final minutes?

You can only feel a fall during the initial acceleration. And surely if the pilots could feel that 10 000fpm decent then they would know they must be stalling and stop the nose up attitude inputs.
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Old 28th May 2011, 12:36
  #692 (permalink)  
 
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Cool

Hi,

Could someone explain to me why there was no distress call in 3 minutes ?
I think they were so busy that if you would ask them their names they would not have been able to respond
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Old 28th May 2011, 12:37
  #693 (permalink)  
 
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Fatal flaw...... It's my understanding the ALL the Attitude indicators where fully functioning all of the time throughout. It was only Airspeed that gave incorrect indications via iced up Pitot tubes screwing the 3 ADM's.
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Old 28th May 2011, 12:47
  #694 (permalink)  
 
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nitpicker330 - I guess you must be right otherwise the flight data recorder wouldn't have recorded it ... so they spent 3 minutes pitched up with the throttles closed and the altimeter plunging waiting for the speed to come back down ... what did they think was happening?
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Old 28th May 2011, 12:58
  #695 (permalink)  
 
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In all the documented incidents so far there has never been an issue with the Inertial Attitude displayed on the primary flight displays or on the separate standby. A simple cross check of all 3 would confirm the same.
Airspeed issues and associated overspeed or underspeed ( or indeed both ) warnings were what happened requiring the crew to look "through" their displays and revert to "basic flying skills"

Oh, and no modern western built transport has an AOA indicator fitted.

Who knows what this crew were thinking, who knows how fatigued they were on the night? Who knows how much Turbulence they were dealing with?

All things being equal they "should" have been able to deal with the situation, obviously all things weren't equal.

Last edited by nitpicker330; 28th May 2011 at 13:29.
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Old 28th May 2011, 13:18
  #696 (permalink)  
 
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nojwod
....... indicate that something either in the instrumentation or the plane's response to inputs was diametrically opposed to what the crew expected to see or experience.
Is there any explanation/reason for the two momentary roll inputs by the PF?
Could these indicate a deliberate check by the PF as in, 'Am I really connected to the control surfaces?'
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Old 28th May 2011, 13:18
  #697 (permalink)  
 
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my comments as a PPL/IMC holder:

If I know that Power plus attitude=performance, so did all 3 pilots there that night. They had power (the engines were working normally) they had attitude info (attitude indicator, not derived from pitots) so obtaining a performance seems the logical way to go. The time the descent took rules out the startle factor, and as is well known, once the descent stabilises at 1g, the seat of the pants feel is useless at best and misleading at worst, yet they still should have had the AI. Again, even as a PPL I know to trust my instruments and ignore the seat of pants sensations. So, why didn't they??
I can see a couple of possibilities- 1. they didn't trust the AI as they were aware of the pitot problems and decided to go with the seat of pants sensations or 2. the stall they found themselves in was irrecoverable due to some design problem or issue inherent in the jets design. No comment whatsoever on AB vs boeing, but don't swept wing jets has a nasty characteristic of entering a flat stall which is hard/very hard to break?
Given the possibility of option 2, and if I were AF or AB I would be looking to promote option (1) since option (2) has the unpalatable effect of admitting that some stalls are invariably fatal, not something which passengers want to hear. So much cleaner to blame it on human error, psychologically, its easier on passengers to believe that the pilots made a mistake, rather than face the possibility that a particular set of circumstances will result in an invariably fatal outcome. What do the stable extroverts amongst us think?
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Old 28th May 2011, 13:22
  #698 (permalink)  
 
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Nitpicker330, (post 700) sorry but I have to call you on that statement. Many Boeing 777's and 737NG's have AOA indicators displayed in the upper right corner of the PFD. Delta Air Lines and American Airlines started this trend back around 2001. It is a Boeing option, you just have to tick the box when you order the airplane and they will deliver the AOA. I believe it's standard on the 787.

Last edited by Spooky 2; 28th May 2011 at 13:24. Reason: new information
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Old 28th May 2011, 13:32
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Fair enough I stand corrected

The info is in the system so it obviously isn't too hard to program onto the display. Maybe it will become a mandatory update for all soon?
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Old 28th May 2011, 13:42
  #700 (permalink)  
 
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Why did the autopilot then auto-thrust disengaged ?

"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 "

At this time, it seems that there were no Pitot problem ?

Why did the autopilot then auto-thrust disengaged ?
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