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-   -   TAM A320 crash at Congonhas, Brazil (https://www.pprune.org/rumours-news/284415-tam-a320-crash-congonhas-brazil.html)

Sl4yer 2nd Aug 2007 14:12


Originally Posted by Johnbr
Iīve been away,flying,so I mustīve missed most of the discussion here....
Has anyone mentioned that the MEL on the A320 states very clearly that in case of one rev.inop,BOTH T/L must be set to Full rev position,thus preventing one of them being left at an angle that would give forward thrust and ensuring that the good reverser will be deployed and G/S will be activated????

Yes. About a third of the way through...

NigelOnDraft 2nd Aug 2007 14:25


Has anyone mentioned that the MEL on the A320 states very clearly that in case of one rev.inop,BOTH T/L must be set to Full rev position,thus preventing one of them being left at an angle that would give forward thrust and ensuring that the good reverser will be deployed and G/S will be activated????
It has been discussed. However, it seems a recent amendment in light of incidents / accidents similar to what is being discussed here. Furthermore, different airlines / nations may feed through MEL amendments in different ways / at different times.

I for instance was not aware of the advice changing from "don't select Rev on the Inop Rev" i.e. if our MEL has been amended, then I have not flown with 1 Rev Inop since the amendment...

wileydog3 2nd Aug 2007 14:41

The -330 crash with Nick Warner was a terrible thing and it happened with one of the world's premier test pilots in the left seat. I flew with Nick a few times and when I returned to the States, I checked around with some other test pilots I knew. Without reservation, each said that Nick could get more data from a test card quicker than just about anyone. I was told he was a consummate test pilot. Still, the accident occurred. It was a long day. Multiple flights in the aircraft and sim as I remember and then the fatal accident.

At times, even the best find themselves in a situation where there is insufficient time to solve the problem.

But an earlier post is correct about looking beyond the NTSB 'x happened'. And the quote about Sidney Dekker is also correct. No one makes mistakes on purpose. And no one intends to crash when they climb into the cockpit.

It is about culture. Culture defines what is important. That influences what is assessed. That influences perspective and that influences what information is pertinent and what is not.. and that influences decisions which move toward outcome and outcome reinforces the culture.

The problem of culture is often only revealed by either an accident or through a FOQA program so what is really happening in the total flight environment is not confused with the supposed environment which is defined in the Ops Manual.

One lesson that may be a take-away and that is in Burbank, the 737 broke traction when the pilot tried to turn. I have read that you can turn or you can brake but often you can not do both and retain traction. Here, we see the crew trying to turn. This is not to say it was the wrong decision but there is cause for thought.

Finally, it is worth considering that there is no such thing as "Business as Usual". There are too many variables in the equation for it ever to be "Business as Usual". Granted, day after day nothing happens and there is a strong lull to accept Business as Usual. And it is hard to keep a keen perspective searching for something that is, most of the time, not there and I will admit that at times I am not as wary or vigilant as I should be. But I have to try. The consequences can be and often are disastrous.

Johnbr 2nd Aug 2007 14:43

Well....I guess I have mentioned this before...I have flown the 320/319,mostly the 319 for almost 6 years...In a very demanding operation,the shuttle between Rio and S.Paulo,in all kinds of weather conditions that occur here,and the machine has NEVER,EVER let me down.
I,sometimes feel very sorry about comments that Iīheard or have seen here or elsewhere on the AB this and that,sometimes made by people who has NEVER flown it...And yes,I have 12 years experience on 737īs both the 200 and 300..."the pilot does not know what the engines are doing"...Jesus Christ!!!! What happened to basic pilot skills that calls for keep on checking all your flight parameters,in ANY aircraft heīs flying,at ALL times,specially during critical fases of flight???I guess itīs still too early to point fingers,particularly keeping in mind thereīs a frantic desire of the authorities to blame this on pilot/machine...At the very previous day we had an ATR skidding out of the runway,didnīt we???

wileydog3 2nd Aug 2007 15:02

Odd. You assert one thing that is not necessarily supported by fact and then ask that the discussion is pointless and it should cease?

The moving/non-moving throttles have been an issue since they were introduced and when I transitioned from Boeings to Airbus, I wondered about it also. But in the years I flew it, I never had any problem knowing what the engines were doing. I fell back on my old training of respect any weakness and play to any strength.

And when I was on the 737, we had an accident in CLT where a 737 landed, hydroplaned and went off the end of 36R. (aside... the airplane went off the end of the runway and wound up resting on a railroad track. Months earlier I had complained to the union and company about the practice of the railroad of parking cars on the track. I was mocked and told there was no way an airplane would make it that far. But I persisted and eventually the railroad agreed to NOT park cars on the extended centerline of the runway. Had there been cars on the tracks that night, there would have been significant fatalities. My point is to always argue the point of safety even it is seems a distant possibility)

Were one to scan the accident record, it would be hard to prove one design markedly better than another without cherry-picking. I flew the 737 during the rudder hard-over era and we spent a lot of time working through that issue. But would I suggest Boeing designs were better/worse than Airbus or Douglas or others based on that flaw? No. Each design has its flaws and good points and the wise aviators knows what they are.

bomarc 2nd Aug 2007 15:09

Murphy's Law

KISS (keep it simple stupid)

Safety in Depth


things will go wrong, so always have an "out"

the out must be simple and fool proof and easily done while in panic mode.

airports should be big with ample overruns in 360 degrees or nearly so of protection.

and don't design for fuel efficency at the loss of safe, simple, reliable operation.

TyroPicard 2nd Aug 2007 15:12

hawk

Question: if we have TLA sensor disagree, does this count as TL idle regarding the spoiler extension logic? in other words, would the ground spoilers extend with TL 1 rev, TL 2 TLA sensor disagree and the lower half of the diagram in TRUE mode (wheel speed or both MLG compressed)?
Short answer... I don't know.
Longer answer .. On the ground, thrust is limited to Idle but REV remains available on the affected engine, with TLA disagree.
The FCOM ECAM procedure does not say that Ground Spoilers are inop, so they should work with that scenario.
TP

Johnbr 2nd Aug 2007 15:26

Wileydog3:
I sincerely beg your appologie.Although it may "sounded" like I was lashing at you I wasnīt...Point taken,I totally agree with your post...Maybe.just maybe the fact that Iīm too close to the events i.e. working for the same airline and having flown the type for few years that it had clouded my thinking...
But,weīve been listening to so much b.s. like "the computer did not understand that they were trying to land" or "the airplane takes over the controls from the pilot" that sometimes I tend to get a little...letīs say...frustrated..Again...sorry pal...

hetfield 2nd Aug 2007 15:31

@NigelOnDraft
 

I for instance was not aware of the advice changing from "don't select Rev on the Inop Rev" i.e. if our MEL has been amended, then I have not flown with 1 Rev Inop since the amendment...
This is a very important information.

@all other 320 skippers

What does you MEL say?

Thylakoid 2nd Aug 2007 15:36

SyEng, I don't fly Airbus, but most airline's SOPs and manufacturer's ops manuals strongly recommend that once on the ground, and with reversers activated, a go-around shall not be initiated.
mtc:)

wileydog3 2nd Aug 2007 15:42

No problem. Often the assertion "The computer doesn't understand" can be translated into "My training didn't teach me what the computer is doing and why it is doing what it is doing."

And though it has been now almost two decades since the -320 accident at Mulhouse, you will still hear, "The computer refused to let the pilot fly the airplane." At that point, you cease trying to argue any point as it is pearls before swine.

I have been very fortunate in that I have been in 3 communities, gen/av, airline and military. And I have also been fortunate to climb in the cockpit of lots of different machines from Airbus to Yaks (albeit very short time in the Yak, Ilyushin and Tupolev).

But each group has its own culture and each community has its own subcultures. Back when I was on the 727, I often jumpseated on different airlines and was astonished at how differently the different airlines operated the same piece of equipment. And if one listened to their arguments of why they did X and not Y, they had sound arguments. Their procedures and training were the accumulation of incidents and accidents at their 'house' and thus it was important to do X and not Y.

And if one thinks it is difficult to change a procedure or practice, try changing a culture. It is close to impossible without some cataclysmic event which has enough force to MANDATE change. And if you want to see a real dog fight of cultures, merge a couple of established airlines. Everyone is convinced the way they do it is the BEST, no questions!

Grunf 2nd Aug 2007 16:49

Re Bomarc's note in post #916...
 
...and the discussion on what is more important: ground spoilers (speedbrakes) or thrust reversers:



Bomarc said (#916)
regarding which do you want first, spoilers or reverse...spoilers should be out before you can get into reverse just as a matter of speed of the spoiler mechanism. :=

Certification requirement is that the airplane is capable of landing with NO THRUST REVERSER(S), but WITH SPEEDBRAKES (and manual braking to max).
Wet runways, including!

There is no statement on spoiler mechanism and it is assumed, when designing the spoiler deployment mechanism, that its operation is essential for landing.

So no speedbrakes deployed is, from certification point of view (in this case both Part 25 and Part 121), a big problem which may or may not be resolved with thrust reverser(s).

Regards,

BOAC 2nd Aug 2007 17:04

Grunf - that may be so for the AB320, but a caution that for landing a 737NG on a 'slippery' runway, Boeing say 2 reversers ARE required for the LDR figures they quote in the QRP.

Mad (Flt) Scientist 2nd Aug 2007 17:16

I suspect those Boeing LDR data are OEM data, unapproved by the FAA, as with much wet/slippery data.

As grunf says, the regs prohibit taking credit for the decel effects of any device which is dependent upon engine operation. So no "certified" distance should include TRs.


25.125(f) If any device is used that depends on the operation of any engine, and if the landing distance would be noticeably increased when a landing is made with that engine inoperative, the landing distance must be determined with that engine inoperative unless the use of compensating means will result in a landing distance not more than that with each engine operating.
Though I will take a slight disagreement about the statement "wet runways, included!". Bizarre though it may seem, especially in light of this and other incidents, 25.125, even at the latest reg, makes ZERO reference to anything other than a dry runway. There are NO Part 25 requirements for landing performance on wet or slippery runways.
One could argue that 25.1301 and 1309(a) required the raw ability to stop on a wet runway (the brakes must "perform their intended function"), but that's a qualitative requirement, not quantitative. 25.735 is about design and redundancy, not brake performance really.

And Part 121 requires a VERY arbitrary 15% planning margin over the dry planned distances for wet - a margin which may bear little or no relationship to the actual degradation in stopping performance on a wet or slippery runway....

Grunf 2nd Aug 2007 17:30

To my fellow Quebecker (and the others):

I was assuming the same from Boeing's Safety Investigation presentation given at 2006 IASS.

Your opinion stands since it is fully based on CFRs.

As for BOACs statement it is in line with CFRs. OEM can give an advisory re. special circumstances. We should expect that in the short run, IMO.
Regards,

Rananim 2nd Aug 2007 17:59

Another AB crash due to the simple reason that the pilot DOES NOT HAVE 100% CONTROL OF HIS AIRCRAFT.And dont let any AB "pilot" with 7000 hours on type come on here and tell you any different and how wonderful it is as long as you know what its doing.Having to predict/second-guess software logic conditions at a time of stress(short wet runway) is evidence of POOR DESIGN and not about the pilot not knowing his aircraft.

At the critical time(just after touchdown),control of the aircraft was in the hands of the computer,not the pilot.The logic conditions to activate the essential retardation devices had not been met.He cant override the software and he cant deploy the spoilers manually.He has NO control.He is not a pilot,but a passenger in a runaway computerized Nintendo nightmare.

Wileydog3,in his infinite wisdom,speaks of each design(AB and conventional)having their strengths and weaknesses and that the aviator must understand them and act accordingly.Thats quite frankly bs.I am tired of wading through these pages and seeing excuses being made for the clear and unequivocal design flaws of this aircraft.By designing the pilot out of the control loop and in a naive attempt to eradicate human error from commercial aviation,they have in fact created a whole new way to crash a commercial aircraft.They've done something only the French could do;eradicate pilot error but replace it with something thats even worse.

The pilot is your last and best chance and he must have full and total control of his aircraft at all times.Unhampered by mode confusion(Melbourne incident,Strasburg crash)),over-confidence in protection systems(Toulouse),or unnecessarily complex logic conditions(Warsaw and now Sao Paolo).No tactile feedback and an over-reliance on the optical channel complete the sorry picture.

Dream Land 2nd Aug 2007 18:11


At the critical time(just after touchdown),control of the aircraft was in the hands of the computer,not the pilot.
I think you are confused, it APPEARS that the thrust lever on the R/H engine was never retarded in the flare (what airplane if any can be landed properly without reducing thrust at landing?), it had to make the aircraft float somewhat, then after selecting REV on the L/H engine, R/H engine accelerates to climb power. This has everything to do with the PILOT, not the computer. :ugh:
(all still theory, not discounting some type of sensor failure until more facts are presented).

hetfield 2nd Aug 2007 18:12

@Rananim
 
I totally agree with your post.

In my flying career, 727 (center/right), A300/310, A320, A340, the last two mentioned gave me most of the headaches concerning system behavior. Every aircraft has it's weakness but the uncertainty on 320/330 (?)/340 about man/machine interface, latest updates to various computers or MEL have reached an unacceptable level.

NigelOnDraft 2nd Aug 2007 18:42

Hetfield <<This is a very important information.
@all other 320 skippers
What does you MEL say?>> Are you implying I should "know" my MEL :( IMHO I need not... It is not "that important information"... it is in a document, and on the day I get an aircraft with 1 Rev U/S, I will then read it and abide by the relevant procedures ;)
NoD

hetfield 2nd Aug 2007 18:44

@NigelOnDraft
 
Hopefully it will be up to date....

Fly safe ;)


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