Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

AF447 wreckage found

Tech Log The very best in practical technical discussion on the web

AF447 wreckage found

Old 31st May 2011, 14:55
  #1161 (permalink)  
 
Join Date: Jun 2009
Location: USA
Posts: 64
Who was PF?

A number of news articles have stated that the PF was the relief pilot, who was the youngest of the crew, had the least amount of experience on type (800 hrs), and the least total flying time. If that is true, and with the captain going for rest, that would leave the FO as PNF. The FO had the most time on type of all the crew (4500 hrs).

None of the BEA reports have stated who was flying at the time of the upset. Perhaps the media obtained the information as a result of a leak. However, this arrangement seems odd to me.

Can anyone familiar with how work would be assigned on trans-ocean flights comment on whether this would be a typical assignment, given that they were about to fly into the ITCZ?
ST27 is offline  
Old 31st May 2011, 15:00
  #1162 (permalink)  
 
Join Date: Aug 2007
Location: Clifton, NJ
Age: 46
Posts: 11
For example, there is not enough informations to understand why the A330 climbed and stalled at 38 000 ft :

> the pilot gives «ordres à cabrer» (pitch-up orders)

> then the PF gives «ordres à piquer» (pitch-down orders)
Actually, I believe there is enough information to determine why the aircraft entered an initial climb after the disconnects - the pilot commanded it to.

Now, I also think that the report is missing some information but the BEA has shared when power settings changed. After the initial AP/THR discconect, no mention of a power change is made - so it is probably at the setting for FL350 and M0.8. The first input is a pilot commanded climb with a max recorded rate of 7,000ft/min. By the time they reached FL375 nose down had reduced that rate of ascent to 700ft/min (I believe that the plane was still climbing at that point albeit much slower than initially).

Without an increase in thrust, there is a trade of speed for altitude. Most likely pilot commanded but turbulence/updrafts may have played a part too. I think if there was an intent to climb over any weather then a thrust setting change would have been made by the PF and none is noted by the BEA.

At 2h10m51s the stall warn sounded. It probably hasn't stalled at this point - the BEA indicates the last 3m30s were stalled and the recording finished at 2h14m28s. That makes the stall a 'fact' at 2h10m58.

John.
matthewsjl is offline  
Old 31st May 2011, 15:01
  #1163 (permalink)  
 
Join Date: Jul 2008
Location: Brussels
Age: 42
Posts: 64
Who was PF?

According to this article, Bonin was the PF. As you suggest this could very well be pure speculation on the part of the journalist - or possibly based on a leak? 'Baby' pilot at controls of doomed Air France Airbus | The Australian
shogan1977 is offline  
Old 31st May 2011, 15:04
  #1164 (permalink)  
 
Join Date: Jun 2009
Location: Bedford, UK
Age: 66
Posts: 1,245
Deliberate climb to get out of icing but with no reliable speed mismanaged thrust ?
Mr Optimistic is offline  
Old 31st May 2011, 15:07
  #1165 (permalink)  
 
Join Date: May 2011
Location: Germany
Age: 36
Posts: 13
Elledan, the Dutch news site is wrong. To be sure of climbing over an ITCZ "lightning storm," the AF flight crew would have to have assumed they might well have to climb as high as 55,000 feet or so, and to do that, they'd have needed the Space Shuttle, not an Airbus. Their sudden climb to 380 had nothing to do with any attempt to top a thunderstorm.
Yeah, that's what I figured. Pilots can fly around a storm, but they can't fly over one. No idea why this news site (usually very reputable) made such a big blunder. Their claim struck me as odd as it was never coined as a possibility elsewhere, especially not on this site

The current conclusion seems to draw towards pilot error with equipment failures and gaps in training as likely contributions. The nose-up inputs especially seem beyond merely curious. I really wonder whether there might be anything about that on the CVR.
Elledan is offline  
Old 31st May 2011, 15:15
  #1166 (permalink)  
 
Join Date: Apr 2005
Location: Australia
Posts: 1,414
Can anyone familiar with how work would be assigned on trans-ocean flights comment on whether this would be a typical assignment, given that they were about to fly into the ITCZ?
ST27 is online now Report Post Reply
The trouble is when a pilot is given "a leg" which is more or less what happened when the second officer was PF after the captain had gone down to have some shut-eye, there seems to be a attitude that as PF he hangs on to the decision making and controls even though the real first officer is more qualified and senior in succession. "My leg" is not carte blanche to be in command unless of course the captain is PF.

Clearly in the Air France case the experienced first officer as PNF should have taken control immediately things went wrong. Of course there was no guarantee the F/O could have saved the aircraft either but the political correctness of "my leg" needs to be examined. In my era the captain would at his discretion offer the F/O a take off and/ or a landing. It was never a case of "your leg" with all that implies. It was always the captain's "leg". Every sector was under the command of the captain and supported by his F/O.

Now it is almost seen as an insult to the first officer if the captain decides to take over control of the F/O's "leg". In the case of the Air France accident it is this politically correct mind-set that may have caused the real first officer to assume the subordinate role as PNF while the second officer lost control of the situation.
A37575 is offline  
Old 31st May 2011, 15:28
  #1167 (permalink)  
 
Join Date: Feb 2003
Location: Kuala Lumpur
Posts: 49
This is indeed an interesting observation, worthy of a study in itself. Where I work, we have a general inkling that CRM has gone 'bonkers'. It certainly was baffling to me why the Captain did not jump back into the seat and 'take over', until explained this way...
CI54 is offline  
Old 31st May 2011, 15:49
  #1168 (permalink)  
Pegase Driver
 
Join Date: May 1997
Location: Europe
Age: 70
Posts: 2,812
Yeah, that's what I figured. Pilots can fly around a storm, but they can't fly over one.
Some unfortunatelty try to do it , it ends up badly most of the time.

In my years as ATC the one I remember best was a transatlantic bound 747 from a major European airline (now defunct) who decided against the 60-80NM dogleg that everyone else was doing to avoid a line of CBs above Belgium. He asked to climb to FL390 to keep its route , then when above dropped down 5 or 6 thousanfds feet right inside. His voice was shaken afterwards. The incident report must still be out somewhere.

2 weeks a go an A320 tried the same thing above Germany, with same results. 3xmayday, dropped 4000ft etc..
Rare events , sure ,but not unheard of.
ATC Watcher is offline  
Old 31st May 2011, 17:19
  #1169 (permalink)  
 
Join Date: Jul 2007
Location: France
Posts: 610
Allocation of (PF) flight legs to crew.

A37575:

It is not a right that every other leg belongs to the F / O or 2nd Captain.

It is the Commander's decision to allocate the legs, if he wants to.

The decision of the Captain, to go to the "bunk" so early in the flight seems strange to me, however he must have had a reason.
Tmbstory is offline  
Old 31st May 2011, 17:36
  #1170 (permalink)  
 
Join Date: Feb 2001
Location: The Winchester
Posts: 5,650
The decision of the Captain, to go to the "bunk" so early in the flight seems strange to me, however he must have had a reason.
Not really, as I think has been mentioned earlier in the thread if it's pure timing we're questioning here then if the Captain had "second break" the timing makes sense.

On the broader issue of him being "off watch" during the ITCZ crossing, personally, I think you have to take into account the fact that he left two fully rated pilots up front - not cruise only copilots. If we're saying a Captain shouldn't ever leave the Flight Deck because inclement weather is forecast in the cruise how do we suggest handling say, traversing Asia or Indonesia during the monsoon season or the North Atlantic if there's forecast of occasional severe CAT all the way across the pond......two Captain ops/no in flight rest ????

(BTW am I alone in often not being able to see the last page of the thread?)

Last edited by wiggy; 31st May 2011 at 18:07.
wiggy is online now  
Old 31st May 2011, 17:43
  #1171 (permalink)  
 
Join Date: Sep 2004
Location: SLF, living somewhere East in the West
Posts: 235
Dumb question

Maybe a dumb question from a dumb SLF - wouldn't it make sense to have a mechanism that blows into the Pitot tube from the inside to test if it is clogged? If there is higher resistance than its clogged and disregard readings. Maybe it can also be cleaned that way...?
grimmrad is offline  
Old 31st May 2011, 18:24
  #1172 (permalink)  
 
Join Date: Jun 2003
Location: UK
Posts: 2,234
Originally Posted by 000tfm000
Some people are better than others at maintaining good situational awareness. I would not belittle training and experience. But even very experienced pilots can become disorientated, as indicated by many sad examples among the accident investigation reports I have studied over the years.

Therefore, IMHO, any instrument which might work counter-intuitively in unusual circumstances, significantly increases the risk of disorientation and its associated consequences if those unusual circumstances should arise.

It remains my tentative view that the stall warning (the one at 2h10min51, perhaps; but mainly the one at 2h1202-17) could well have seemed to indicate that the nose-down inputs were for some reason causing the aeroplane to enter a stall, so discouraging the PF from developing the very inputs which might have led to an exit from the stall.
I too shall declare my interest: A320 Captain.

I really don't know where to start with this thread. So much noise, so little signal. The number of red herrings and long irrelevant side tracks is so great that no one can even start to address them.

The PF quickly and correctly diagnosed the situation. Loss of airspeed indication, resulting in AP/AT off and Alternate Law. He then incorrectly pitched up to 10° until the AoA was just 2° from the stall.

In this perilous position, the AoA increased again to 6° and the aircraft stalled. The response was incorrect with TOGA + pitch up.

So, two apparent errors. So much has been said about the wrong procedure being used (TOGA + pitch up is used in many other procedures) and a lack of training that I won't bother. But here is something frightening:

Most older Airbus pilots have done their time in cranky old jets and turboprops, where you fly by pitch. Everything is done by pitch settings - choosing, setting, adjusting, waiting and so on. However, in the world of the safety committee it is fine to pluck young lads straight from a Seneca and place them into an Airbus. To mitigate the risk, the flight director must be on at all times. Now all the cadet has to do is put the square in the centre of the cross. Never has a pitch been noticed nor noted.

I asked 5 first officers in the cruise to look me in the eye and tell me what pitch we were at (2.5°). 4 cadets answered between 5° and 10° , and one ex TP guy answered correctly at 3°. Not much of a sample, but indicative I suspect.

The Airbus is a fine aircraft. It is conventional, and simple. On top is a thick layer of cotton wool, that should protect us from our silly mistakes.

Once the cotton wool is removed, we are back into a simple jet. The snag is that with the current drive to train/recruit people as quickly and cheaply as possible, not one of the recent arrivals has ever flown in "simple jet mode" (by pitch and thrust). Incredibly in our airline it is now even prohibited to take off with the flight directors off.

I feel sorry for the two FOs on the flight deck. Without the FD they will have been in new territory. Without the airspeed, it is no time to have to guess pitch settings and develop a strategy to keep the thing in the air.

I hope the airlines have a good think about this. I imagine the safety departments will, but nothing will happen due to the cost of recruiting people with experience on conventional types.

PS: Below 60 knots I imagine the stall warning is inhibited because there is not enough airflow over the AoA vane to make it accurate and trustworthy.

PPS: Has any Airbus pilot here ever actually heard the stall warning in the sim?
HundredPercentPlease is online now  
Old 31st May 2011, 18:30
  #1173 (permalink)  
 
Join Date: Aug 2009
Location: Germany
Age: 63
Posts: 1,809
Cool

Hi,

(BTW am I alone in often not being able to see the last page of the thread?)
NO ... methink it's a bug in the forums
Sometime it's more than 1 false "last page"
jcjeant is offline  
Old 31st May 2011, 18:32
  #1174 (permalink)  
 
Join Date: Feb 2001
Location: The Winchester
Posts: 5,650
I asked 5 first officers in the cruise to look me in the eye and tell me what pitch we were at (2.5°). 4 cadets answered between 5° and 10°
You're right, that's frightening.
wiggy is online now  
Old 31st May 2011, 18:40
  #1175 (permalink)  
 
Join Date: Sep 2010
Location: UK
Posts: 218
To mitigate the risk, the flight director must be on at all times. Now all the cadet has to do is put the square in the centre of the cross. Never has a pitch been noticed nor noted.
Blimey, which airline do you fly for? I'll make a note not to fly with them as there appears to be some serious shortfalls in your training department.
Yellow Pen is offline  
Old 31st May 2011, 18:49
  #1176 (permalink)  
 
Join Date: Aug 2009
Location: Germany
Age: 63
Posts: 1,809
Cool

Hi,

There also would have been heavy buffeting. Given that they were flying at night in a storm, the passengers would have had no outside references to know what was happening, and would not have known they were falling. A clue would have been the change in cabin pressure, but how many passengers would connect that with rapid descent?
Maybe all this is right ...
But passengers also have ears to listen ... and I am than most (at least those who were not asleep or woke up) will have noticed changes in engine speed .. and it will have more of a worry about .. even if they did not know that the plane was heading towards the sea
Moreover, I wonder what that could be displayed on the seats screens .....
jcjeant is offline  
Old 31st May 2011, 19:02
  #1177 (permalink)  
 
Join Date: Jan 2008
Location: Denver
Posts: 1,028
(BTW am I alone in often not being able to see the last page of the thread?)
Aside to wiggy - No, you aren't alone. But it just a forum housekeeping thing. As Page 59 (e.g.) gets nearly full, an empty Page 60 gets created. But until the posts actually flow over to page 60, you can't get to it (and there's nothing yet to see anyway).
pattern_is_full is offline  
Old 31st May 2011, 19:13
  #1178 (permalink)  
 
Join Date: Jan 2008
Location: UK
Posts: 12
PS: Below 60 knots I imagine the stall warning is inhibited because there is not enough airflow over the AoA vane to make it accurate and trustworthy.
Well they were descending, stalled at ~120 Knots with the AOA sensors exposed to the airflow, so the sensors should have been providing useful info. Can anyone explain therefore the logic in inhibiting the stall warning with no weight on wheels? Maybe not the first hole in the cheese....
timpara is offline  
Old 31st May 2011, 19:21
  #1179 (permalink)  
 
Join Date: Jun 2009
Location: France
Age: 79
Posts: 41
It is not a right that every other leg belongs to the F / O or 2nd Captain.
Do the number of hours an FO has flown as PF count for his/her career progress ?
milsabords is offline  
Old 31st May 2011, 19:24
  #1180 (permalink)  
 
Join Date: Jun 2003
Location: UK
Posts: 2,234
Yellow Pen,

I over egged. The flight director must now be on for take off and initial climb out. It may be off for an ILS if conditions are suitable, and will be off for hand flown visuals.

However with the level of inexperience we now have, not many captains will be so happy at the thought of a <500 hour pilot flying a raw data ILS, when most approaches and landings with a full house of aids can be just a tiny bit "variable".

We have an industry wide reputation for having an excellent training department. However we (like many other airlines) now refuse to recruit experienced first officers, and restrict ourselves to Seneca -> Airbus low hour contract first officers. Hence my point - many recent Airbus pilots may have no experience of flying a jet on pitch and thrust alone.
HundredPercentPlease is online now  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.