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Some additional news on the Air France Atlantic crash

Started by Phil Bunch, Tue, 17 May 2011 17:30

Phil Bunch

Another news story, with some additional details and speculations:

http://online.wsj.com/article/SB10001424052702304066504576349112775425674.html?mod=WSJ_hp_mostpop_read

Title and subtitle:

"Crash Report Shows Confused Cockpit"

"Pilots of Ill-Fated Air France Flight Tried to Halt Loss of Momentum by Tilting Nose Up, Not Down"

Also, click the graphic, "final minutes..." for a graphical summary.

Does anyone know or wish to speculate on the angle of the aircraft with respect to the sea surface?  In other words, was the thing falling out of the sky nose-first or in some other attitude?  (just curious...it's not exactly a time to fly by the seat of one's pants...)

I am also puzzled as to how an apparent stall wasn't saved in an orderly fashion.  3.5 minutes is a long time, as others have commented.  

Should the pilots really be blamed?  Personally, I usually look for systems issues when something goes badly wrong like this.  The full report is needed before one can realistically pass judgment, of course.  

The news media are poorly motivated and ill-equipped to make rational assessments, but who can resist at least skim-reading their stories?  I wonder if they are somehow obtaining bits of inside information?
Best wishes,

Phil Bunch

John H Watson

#21
QuoteLet's enter a transport aircraft cockpit, look at the landing gear extend/ retract control, apart from the very latest, such as B777 and modified B744, why are there 3 handle positions where the gear has only two desired positions? How many decades were required to change this? why? Should a pilot care what is happening to hydraulic fluid or limit stops, or should he mostly supervise aircraft operation while free to maintain situation awareness and make appropriate decisions?

It took them decades to trust electronics instead of steel cables. Now these latest gen aircraft have absolutely no mechanical backup.

Let's hope the batteries don't go flat*  :mrgreen:

The two position lever is possible because the electronics produce an OFF position.

I don't think the average pilot is intimidated by a 3rd position. Non-Normal checklists tell them where to put the lever for gravity extension.

Rgds
JHW

*P.S. Seems as though it wasn't so long ago that a 744 was running on Standby Power only, and depleting it's batteries at a great rate. Flat batteries = no gear extension

Zinger

#22
I flew aircraft with 2 position gear handles from the early 60s. They also had a gear lowering backup system and the only thing requiring electricity were the gear position indicators. We used to practice using them  more than a few times, the right hand pumping and the left flying.
The Boeing engineers likely believed flying on standby electric power would be highly unlikely, else they would have done smarter. Today I'd guess they realize that.
Regards, Zinger

Jeroen Hoppenbrouwers

#23
Would we really see another case of pushing on for minutes with six eyes in the cockpit missing "the elephant"? Like Turkish at Amsterdam (though a different malfunction)?

Jeroen Hoppenbrouwers

Quote from: Phil BunchDoes anyone know or wish to speculate on the angle of the aircraft with respect to the sea surface?  In other words, was the thing falling out of the sky nose-first or in some other attitude?
"Examination of all of the debris confirmed that the airplane struck the surface of the water pitch-up, with a slight bank and at a high vertical speed,"
this was already established a long time ago.


Jeroen

tl1975

#25
Quote from: Jeroen HoppenbrouwersWould we really see another case of pushing on for minutes with six eyes in the cockpit missing "the elephant"? Like Turkish at Amsterdam (though a different malfunction)?

And don't forget Helios..... what a shame....

tl1975

#26
Quote from: ZingerShould a pilot care what is happening to hydraulic fluid or limit stops, or should he mostly supervise aircraft operation while free to maintain situation awareness and make appropriate decisions?

Reading this, I have a strong urge to comment on it:
You know how long a gear handle can remain in the up position after it has been raised, before you put it in OFF (mid position)?
Hours! (it's not good, I agree, but a midair isn't good either)

I've seen many 3-position-gear-lever-pilots having the bad habit of prioritizing gear UP to OFF selection above scanning and SA.

So, yes, the simpler the better. Fully agree. But if it isn't due to design or philosophy , don't make it even more complicated by moving secondary activities to first.

See, old aircraft are still able to fly in 2011. The drawback is a higher workload, more crew and more training: expensive! (lets skip environment for now)

We all should agree that nowadays aircraft are build in a way to reduce crew training and crew competency (all very costly). Airlines prefer to spend more money on high-tec aircraft than on crew training.

We have to face that although less likely than before, WHEN it goes wrong, it goes horribly wrong.
In old aircraft a horribly wrong situation could possibly be saved. In new ones, you're happy to discovery WHAT is wrong in time to realize there is no time left for you to fix it.

I agree, a bit overcharged. But still.
 ;)

Mundyas

Good morning

According to a Sky News quote yesterday  talking  about the recently issued bea report.

"Bea Director Jean-Paul Troadec said 'These are so far observations not an understanding of the events'."

So in a couple of months the full report will be out.

Anyway an incredibly sad event.

Andrew

Mundyas

Reading comments on the press on this forum reminded me of the fictional TV report in the book Airframe by Michael Crichton

Talking about an engine incident on an aircraft the TV reporter said"Seconds later, the plane was rocked by an explosion as the left starboard engine literally blew to pieces ..."

Zinger

#29
QuoteSo, yes, the simpler the better. Fully agree. But if it isn't due to design or philosophy , don't make it even more complicated by moving secondary activities to first.

I didn't define the 3 position landing gear handle a major design deficiency. I gave it as one example of a multitude in the pilot's workplace, depicting a typical situation in a manufacturer design team.  An engineer whose interface with a pilot, to understand the human factor, not the technical specification, in the cockpit during flight under heavy workload, is probably limited to a lifetime experience of 5 minute converstaion near the drawing board.



QuoteSee, old aircraft are still able to fly in 2011. The drawback is a higher workload, more crew and more training: expensive! (lets skip environment for now)
It depends on the design and the mission. There are some I've flown in which the pilot becomes comfortable in minutes and can perform well with little work (e.g,. Dassault Mirage III/ V), while others are the opposite. The were more than one British older fighters, where after liftoff the pilot had to change stick hands more than once to raise the gear and flaps, and this saga went on during the flight with other systems. Just placement common sense would have done away with that.

QuoteWe all should agree that nowadays aircraft are build in a way to reduce crew training and crew competency (all very costly).
We have to face that although less likely than before, WHEN it goes wrong, it goes horribly wrong.
In old aircraft a horribly wrong situation could possibly be saved. In new ones, you're happy to discovery WHAT is wrong in time to realize there is no time left for you to fix it.

It isn't a God given rule. Training now involves with much fewer cockpit workforce much more complex CRM. IMHO mostly cumbersome and unnecessary. The cost of training is driven by unnecessary regulation, as Jeroen H called it- MBA managers. From a little experience in the area of pilot selection and training, I'm saying that it should be reduced by better quality training. My son recently completed B737NG type certificate, for which he devoted a few weeks in class and a short workweek on the KLM simulator, enabling him to fly commercially in Europe in both feet and meters.  Effective and non-costly training. He'd have no problem recovering inverted spins, let alone get out of a stall.
Regards, Zinger

Jeroen Hoppenbrouwers

Elsewhere, amidst a heap of trash postings, I discovered some people talking about the possibility of a total or near total loss of displays. Not that they blanked out, but that some critical systems would revert to "I don't trust myself" mode after having received known bad data. With a PFD full of flags and unclear readings, in pitch-black night without a visible horizon, how likely is it that three experienced crewmembers all think that the altimeter is lying and the V/S indications (if at all available) are flawed?

Could it be at all possible that they honestly did not notice they were moving mostly vertically?


Jeroen

John H Watson

QuoteI flew aircraft with 2 position gear handles from the early 60s. They also had a gear lowering backup system and the only thing requiring electricity were the gear position indicators.

I'm sure there were lots of aircraft with two position gear handles, but they didn't weigh 400 tonnes, have 18 wheels, carry 350 people and the pilots didn't sit 100 feet from the main gear :mrgreen:

Holger Wende

Hi,
According to The Aviation Herald situation is confusing:

Essential information of flight attitude seems to be removed when considered invalid, e.g. airspeeds are removed below 30 kts and AoA indications is removed below 60 knots.
And according to the sequence of the events I assume the attitude information and airpeeds at least were not availble continuously, pilots stated they had no (valid) indications.

This situation is bewildering to me:

On the one hand some information is hidden from the pilots when systems regard related data as unreliable (incl. the stall warning  :shock: ).

On the other hand this (unreliable?) information is available and recorded somehow and used to analyse the flight.

Can you really trust the recorded (potentially unreliable) parameters for later analysis?
Or if recorded data are more reliable than displayed data why not make such raw data available to the pilots?

Sinkrate recording worked well so I wonder whether sinkrate indication was displayed continuously?

As Jeroen said, I also wonder whether the pilots were really aware of their deep stall with some information coming and going on their displays and no reference in the a black night  :shock:

And I remember having seen a report in the German TV when 2 experienced pilots were trying to "re-simulate" the situation in a professional flight simulator (of course based on very vague assumptions of May 2010).
Outcome: They were not able to deal with the huge number of messages displayed fast enough (German link only: From Google Cache: Flugzeugabsturz).

This also reminds me of the uncontained engine failure of an A380. The crew requested they would need about 30 minutes to process the ECAM messages... Different situation of course but still very long for error analysis.

Regards, Holger

Zinger

#33
Jeroen,
While any such possibility cannot be rulled out, here is what real flying looks like. I was part of an air operation where a Boeing 377 Stratocruiser on a photo-reconnaisance mission at 28,000 was hit by an SA-2 missile, entered a spin and hit the ground. I talked to the flight engineer who parachuted safely moments later. He described the experienced crew as frozen in their seats, and wouldn't respond to his calls to get out, time was ample. All 9 others perished, people I closely knew to be top notch, mindful, athletic, experienced.
John,
you win, that aircraft was and still is an aeronautical masterpiece if not marvel. Two close friends were chief pilots on it, no words to describe their joy. I still remember my first passenger ride in it HKG -> NAR on Cathay, 1989.
Regards, Zinger

Zinger

As I recall, a standby artificial horizon installed in such aircraft is supposed to be automomous, and be powered for 30 minutes by its own battery. I am not sure how the more articulate integrated unit works, but imagine that at least the horizon part works as above, possibly even with its own illumination.
Regards, Zinger

Jeroen Hoppenbrouwers

#35
The 744 ISFD is a completely standalone device indeed. It does not even need power, it does have its own battery and IRS (but I forgot whether its dedicated battery was inside the unit, or down in the MEC!). If you take it out of the panel while it is alive, you can tilt and shake it, and it will respond and keep the horizon level with reality. You can also notice that this one isn't of the same design style as the PFDs, it is more crude, and I presume it comes nearly straight out of a military design.

Many modern Boeings seem to share this same instrument (barring for face place colour).




Zinger

#36
It is so "crude" that all I'd need on the main instrument panel except it are ND and MCP.
Regards, Zinger

Jeroen Hoppenbrouwers

#37
"Crude" as in "esthetically unpolished" -- not as in "not useful"!

Airbus seems to go with the same  box with some mods.



torrence

That is a truly chilling report.  I saw some of this reported in the Int'l Herald and could not understand the repeated reference to nose up inputs.  Still don't.  It seems, no matter what the air speed indicators were doing they must have known they were in a stall (horn sounding several times in the sequence).  All stall recovery procedures I'm familiar with start with nose down pitch commands.  Is it even possible that the 'alternate law' call when the auto systems disengaged was not heard correctly and the PF responded assuming the AOA protections were still in place ??  I'm a non-pilot and  have virtually no detailed knowledge of Airbus equipment or procedures, but am confused.  Am I missing something obvious?

Torrence
Cheers
Torrence