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

S. Dumont 1st Aug 2007 15:20

Gentlemen,

I'm ashamed to what I just witnessed on the local TV. Congressmen reading the transcripts of the CVR on the TV, and even worse, with extremely inaccurate translation (transcripts were in English, and were translated by one congresswoman who had experience in the language but no knowledge in aviation whatsoever).

Going against all the ethics on accident investigation, without respect to the victims and their families. Such events sometimes make me feel ashamed of being Brazilian.

I'm extremely sorry things had to take this course. I think now it's time for ICAO to take more severe measures.

...

Jose lourenco 1st Aug 2007 15:22

This just came out on Brazilian TV.
One of pilots says:
(Free transnlation)
""Douchdown sound
FWC:"Retard, Retrad!
No spilers!
I`m not been able to deaccelerate!
Turn it! Turn it
Oh my God...
Male Voice
Female Voice
End of transmission

marciovp 1st Aug 2007 15:27

Translation
 
The article in "Folha" was written by a reporter that got information from someone who listened to the tapes. He started by saying that yes the right engine lever was forward before touchdown instead of being on neutral. As the plane landed the electronic system of the airplane interpreted this as the pilot wishing to accelerate and the two engines accelerated automatically. The aerodynamic brakes did not start and the automatic brakes of the wheels did not work. Only the left throtle lever was on rev position. The right one not. The right remained accelerating. The investigators from CENIPA said "the data may indicate that the lever was in such position but who knows if there´nt was an electronic problem?... ... One can hear something like (in the voice recorder) that the lever doesn´t move, is jammed (enroscado)". As the plane touched down uma voice said: "Reverse only one". Then, "Nothing with the spoilers..." (that is they did not work). Then a dramatic calling "reduce acceleration, reduce aceleration, reduce acceleraton" (desavelera, desaclera, desacelera). The panic increases: "Impossible, impossible, impossible" (não dá, não dá, não dá). Then, "turn,turn,turn" (vira, vira, vira).

Tree 1st Aug 2007 15:31


and again, will someone confirm that you cannot manually deploy spoilers in config-full?

You cannot in config Full but you can in config 3.

RatherBeFlying 1st Aug 2007 16:07

You expect to hear increasing revs when putting an engine into full reverse. Perhaps for a few critical seconds the increasing revs on #1 masked the increasing revs on #2.
So then the crew catches on and, if press leaks are correct, is unable to get TL2 to idle. Did the TL lever mechanisms interfere with each other?
Until the timestamps come out, we do not yet know how far down the runway they were when they realised their problem, nor how much runway was consumed while they were trying to resolve the problem.
So there you are with no spoilers on a slick runway; so you're not going to stop -- but one engine is in reverse; so your changes of getting it back into the air are slim to none.
EMAS is designed for a 70 kt excursion, but cutting off the fuel and keeping it straight may have had it down to some 40 kts before departing the EMAS.

Kinetic energy being the square of the speed yields a reduction of:
94 x (70 x 70 / 94 x 94) = 52

hetfield 1st Aug 2007 16:09


is it possible for the thrust lever to be locked into the climb detent, perhaps as a function of landing with thrust lever in climb?
I think it's nearly impossible that TL can be locked mechanicaly wise, BUT it's possible to have a THRUST LEVER FAULT.

This means the electronic TL-command is stuck.

bsieker 1st Aug 2007 16:15

Airbrakes vs. Ground Spoilers
 
To clarify the "spoilers in FLAPS FULL" issue:

The A320 has 5 spoilers on each wing, that perfom three different functions, that should not be mixed up:

- Spoilers 2, 3, 4 are used as speedbrakes in flight, these can be deployed in Flaps configurations 0, 1, 2 and 3, but not in FULL (4).

- Spoilers 1, 2, 3, 4, 5 act as ground spoilers to decelerate the aircraft after touchdown and at an aborted take-off. They will deploy regardless of Flaps configuration, if the conditions are met.

- Spoilers 2, 3, 4, 5 are also used for roll control. Roll control has priority over speedbrake function in flight for spoilers 2, 3 and 4.

SyEng 1st Aug 2007 16:48

Memory action on no decel
 
Can any A320 (preferably) pilot tell us whether a "memory action" is taught during training for the eventuality of a "no decel" (and/or "no spoilers" and or "no brakes") call? If so, is it to go to TOGA and do a go-around? If not, why not?

dalillama 1st Aug 2007 16:49

I'm a non-AB driver, so could someone explain to me what is the logic for TO/GA?
Could, in this case, the AB have executed a TO/GA for some reason, while the pilots braked?
What is the detente or resistance for a TO/GA in an AB? Is the pilot physically able to stop a TO/GA by just pulling back on the throttles?
The comment about "enrosca" (it's stuck) sounds awfully like the AB went into some automatic TO/GA logic and the pilot didn't figure out how to counter it in time.

Thanks!

DozyWannabe 1st Aug 2007 17:14


Could, in this case, the AB have executed a TO/GA for some reason, while the pilots braked?
In a word, no.

Unless they advanced the levers to the TOGA position, which apparently they did not. It's a common misconception that the AB computer 'overrides' the pilot's command. Unless alpha floor is active (above 100ft RA) it will do *exactly* what the pilot tells it.

J.

GearDown&Locked 1st Aug 2007 17:17

To AB pilots: Have any of you ever heard of an electrical/electronic malfunction of the T/L system, and what to do with it if it fails?

If this was the case and reading back some of the previous posts regarding T/L logic, a thrust lever being "stuck" at different logic position from its mechanical one could be the source of some serious problems, specially at these critical phases of the flight.

dalillama 1st Aug 2007 17:26

So I'm guessing there's no mechanical deterrent that would prevent the pilot from reducing power, regardless of whether or not TO/GA is activated, right? Again, I'm looking for a possible reason why the pilot would state that the TL is "stuck". I haven't seen the accident report from the Phillipine Air Lines crash, but I've heard conflicting reports that he stated he had a "stuck TL" as well.

c9jfb 1st Aug 2007 18:00

Quote:
Unless they advanced the levers to the TOGA position, which apparently they did not. It's a common misconception that the AB computer 'overrides' the pilot's command. Unless alpha floor is active (above 100ft RA) it will do *exactly* what the pilot tells it.

I am not an AB driver too but the statement of TL being some what stucked remind me the automatic TOGA done by Alfa-Floor.As you said this is turned off above 100ft RA. Any one can tell what can happened if one engine is being full throttled for take-off and the other oposing the aceleration? Could an extra power requirement to overcome the drag demanded TOGA and lock the TL as it does with Alfa floor?

bsieker 1st Aug 2007 18:25


Any one can tell what can happened if one engine is being full throttled for take-off and the other oposing the aceleration? Could an extra power requirement to overcome the drag demanded TOGA and lock the TL as it does with Alfa floor?
No.

Alpha-Floor Protection is the only situation in which the computer applies more thrust than the thrust lever angle indicates.

Even if we assume that the thrust lever was indeed left (or even "stuck") at Climb, that is not "full take-off power".

Nothing can lock the thrust levers.

And I hate to repeat it, the computer does not take over, or just does something it thinks is right. It doesn't think, it does what it's told, while preventing you from doing some (but not all) really stupid and dangerous things, such as stalling the aircraft. Or flying a loop or a complete roll.

Heathen_Sol 1st Aug 2007 18:32

Is there even such a thing as "rejected landing"!

The procedures for rejected take-off are set in stone but are rejected landings practised for in sim?

Have there been many incidents were an aircraft has fully touched down on runway but due to braking failure/spoiler failure/no deceleration on short runway have the crew had to stop landing procedure and taken steps required to take off again?

James7 1st Aug 2007 18:41

FWC
 
Flyingnewbe - Updating the software on the AB is not a problem it is actually being done continuously. Not very often but there have been several software updates. Just a matter of replacing a computer card into the FWC. Could be done in an hour or so.

Manual Spoliers can be used in Config Full when on the ground.

The thrust lever could only be stuck if it was Jammed by a foreign object. Alpha Floor does not lock the thrust lever - it locks the thrust. The TL can still be moved. There is no motor that drives the TL they must be moved by hand.

To overcome the ecam 'thrust lock' - Move the TLs.

Releasing of the FDR/VR in this way is absolutely scandalous. IMHO.

Jim

Watchdog 1st Aug 2007 18:54

I recall from my A320 days that:

GND SPLRs deploy when: 2 MLG on gnd with BOTH TL @ or near idle.
AUTO BK: Triggered by GND SPLR operation (after appropriate delay).

It would follow then that if one TL was either not at idle, or not sending 'idle signal' to the SECs, then some factors of this tragic scenario MIGHT be explained (if the above report is what the investigators find).

(I stand corrected from those current on the 320 family)

hetfield 1st Aug 2007 18:55

@flyingnewbie10
 
Is there a way to add/update/change ECAM warning messages (from the FWC) ?

Yes it is! The operator (airline) can do a so called "pin programming".

So you have customized call outs, warnings, etc.

E.g. some airlines have a warning if you start the engines with TL above idle:ugh:, some don't.....:ugh:

marciovp 1st Aug 2007 19:09

Proud Brazilian
 
I am a proud Brazilian but lately I have been somewhat embarassed by the way these aviation accidents are being handled. In case you don´t know there is now a lot of people involved in deciding what went wrong. Let us start with our President that soon after the accident with TAM asked the Federal Police (FBI) to investigate to determine who is to blame. Of course the government was in the defensive because of Congonhas runway, its responsibility. Then there are Investigative Committes (CPIs) at the House of Representatives and the Senate. They do their own investigation and very few have the least experience with aviation. Then there is CENIPA the organ from the Air Force that investigates accidents. But the Air Force also administers the Air Traffic Control (equipments, softwares, controllers (almost all of them). Sometimes the State Police gets in as I believe is the case with São Paulo. And so on... What is happening now is that CENIPA got all the data from NTSC but was pressed to release them to the CPI of the House and then things started leaking. In a previous accident CENIPA had to relase the data to the Federal Police by a court decision... CENIPA say that it will take 10 to 12 months for them to release a final report... And so on... This embarasses me because I know how things work in the USA with the NTSB and FAA. Hope I am not going off track.

Tree 1st Aug 2007 19:10

From the FCOM (abridged)

Speedbrake control (lever):
Spoilers 2,3,4
Inhibited:
Flaps in Config Full etc.

For maintenance purposes lever will extend # 1 surfaces when stopped on ground whatever slat/flap config.

Ground spoiler control: Spoilers 1,5

Armed with speedbrake lever (pulled up to armed position)
Auto extension when both MLG touched down when Ground spoiler armed and all T/L at or near idle or reverse selected on at least 1 engine (other T/L at or near idle) if ground spoilers not armed.

Ground spoilers retract:
when ground spoilers disarmed etc.
Based on that information: Spoilers 2,3,4 can be extended after touchdown using the lever if in config. 3 but not Full
Ground spoilers cannot be extended manually by moving the lever rearward after touchdown. They are only automatically extended and retracted when a series of electrical continuity conditions is met; one of them being the switch activated by pulling the lever up to the armed position. Moving the lever rearward has no effect other than during the maintenance function described above.


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