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

armchairpilot94116 2nd Aug 2007 08:39

hands on flying !!
 
This pilots got his aircraft under control . Hand flying, keeping an exact pulse on the plane under you. Not good to get away from that.

http://youtube.com/watch?v=1LHwYoT4Bho

atakacs 2nd Aug 2007 08:40


The co-pilot at this point could not interpret whether the engine without the reverser deployed would have a abnormally high N1 (EPR) power because he cannot compare with the other engine (which is on reverse thrust)
that's an interesting point but wouldn't the co-pilot expect to see one engine producing thrust and the other at idle ?

vapilot2004 2nd Aug 2007 08:48

I am not (yet) rated on the A320...
 
Volume:

Could anybody enlighten me, whether the flight spoilers are available during any phase of the flight, even close to the ground with the flight controls being in flare law, at all flap settings, with U/C down?
Flight spoilers are always available via manual control unless any of the following is true:

>>REV SEC 1 & 3 fault**
Elevator Fault
Alpha or AOA protection active
Full flaps set
TLs are greater than MCT

** Revised

Flight spoilers (speedbrake function) are controlled via the SEC (Spoiler/Elevator Computer) #1 & 3. The #1 & 3 SEC control Spoilers 1-4. Speedbrake function uses panels 2,3 & 4.


Max deflection (in degrees) of flight spoilers:

Spoiler-----Autoflight--------------Manual Flight
#3 #4............25...............................40
#2...............17.5 (12.5 Config 3).........20


Max deflection of ground spoilers is 50 degrees unless partial lift function is called then it is 10. (see earlier posts on this) Ground spoilers (#1-5) are actuated via SEC 1,2 & 3.


Will there be an auto spoiler function (armed spoilers, lever pulled) if one T/R is inop on the A320?
Ground spoilers will activate despite having a T/R inop. Please see earlier posts for more on this.


Papagaio:

as you touch-down and you see NO ground spoilers deploying, in that case a go-around could be initiated because you've got eng-2 (rev pinned) ready to go and lots of speed (even if you got eng-1 retracting the shells you'll be up to flight speed in a second or two)
Please see earlier posts on this. Once the T/Rs are deployed, one is earthbound unless you have a surplus of runway ahead. This is the case with most civilian jet aircraft.

papagaio 2nd Aug 2007 08:51

what is idle power EPR? less than one... but EPR on the engine on reverse is higher than one, it's difficult to compare just with a known value in your head ... I've never looked at the EPR on landing and thought it was too high or low... also because the idle-EPR value changes for each regime of flight. There's no time... you only look whether the reverser is green! then you monitor speed! They did see the speed was high but did not know why!!!
Rds

TyroPicard 2nd Aug 2007 08:57

Moving Thrust Levers and Autothrust.

Scenario - engine runs down on approach.
You are stable at Vref, in landing configuration, thrust stable, hands and feet on controls and thrust levers. An engine runs down. You observe speed decay and roll, possibly yaw. (I know the a/c will yaw, but you may not notice.)

The thrust levers advance - fine, you accept that autothrust is increasing power to compensate for the speed loss.
BUT you can only tell quickly what has happened to the engines by looking at the engine instruments. Did you all read that? You have to look at the engine instruments. Competent pilots with moving thrust levers regularly scan those instruments to make sure the engines are doing what their hand tells them. Competent pilots with stationary thrust levers regularly scan those instruments too!

I have enjoyed flying both Boeing and Airbus types. But the best airliner I have flown was built by Douglas.
TP

papagaio 2nd Aug 2007 09:03

have you done reverser unlocked at or near V1 and decided to GO? It goes! eng-2 was available to go... but I agree only tests could know for sure. Fact is that the spped didn't decrease and was very close to flight speed. All he needed was to take the feet off the brakes and TOGA on both. Or else AB must change short-runway landing procedure. A brake fault could have caused the accident too!
What do you think?
Rds

papagaio 2nd Aug 2007 09:09

That's exacly my point. Whenever you have a thrust change you'll know (if you have a throttle movement) and thus check the instruments! On the AB, this scenerio would have passed unnoticed! don't you agree. A good "ABdriver" reads his FMA!!!
Rds

paull 2nd Aug 2007 09:43

So what is the procedure for T/L stuck or sensor error on landing?
 
I'm not a pilot,

So, you get Retard, Retard, - "oops did we miss a trick?" (thats 3 seconds).
No, the T/L is ok, it must be a sensor error, so you move it out and back in case it is intermittent, still "stuck" (either physically or logically) , now what?
There must be a procedure for something as simple as a T/L sensor failure, after all a failure of either one of them screws the spoiler deployment.
Surely it has to be
"Retard, Retard -"oops did we miss a trick?" , No , Go Around.
I still find it worrying that there is no way to manually deploy the spoilers in this case, even with the time that a Go Around gives you. Someone mentioned cutting the fuel off an engine - that fixes the thrust problem but it does not allow spoiler deployment. Can you flag an engine as InOp as you land and will it then be excluded from the spoiler deployment logic?

So Airbus, what is the procedure for a T/L sensor error?

TyroPicard 2nd Aug 2007 09:46


On the AB, this scenerio would have passed unnoticed!
Do you mean engine failure on the approach would pass unnoticed? What a wonderful aircraft!
TP

TyroPicard 2nd Aug 2007 09:56

paull
There are two Angle sensors on each Thrust Lever. If the two sensors disagree about the TLA, on the ground, but not at TOGA or FLX/MCT (i.e. take-off thrust setting), the FADEC selects Idle thrust irrespective of thrust lever position. An ECAM warning occurs and as part of the drill the pilot backs this up by selecting idle.
If neither sensor produces a valid signal, on the ground, the FADEC selects Idle thrust. An ECAM etc......

FADEC= Full Authority Digital Engine Control
TP

Dream Land 2nd Aug 2007 10:15


Quote:
Reverse thrust is the first thing you want to see on a short wet and slippery runway
:eek: :eek: :eek::mad:

Quote:
by Kit d'Rection KG
No, that would be ground spoilers. Just reassure me - you don't fly a big aeroplane, do you?
:} I totally agree!

But what I wanted to stress is that the PF real preoccupation and first action on a short and slippery runway will be asap to set TLs to full reverse by config full
Config, where I disagree with you is in your thinking that upon arriving at a short runway, reverse will save the day. My thinking for landing on an airport that going off the end (if there is one) is a possibility, you do not commit yourself (T/R's deploy) until you have effective braking, period. So if there's a cliff at the end of the runway, my thought is being "go around" minded, not "committed" minded, just my 2 cents.

TioPablo 2nd Aug 2007 10:16

Thanks!
A very good question!!!

paull 2nd Aug 2007 10:25


paull
There are two Angle sensors on each Thrust Lever.
Thanks TP, I guess we can go with those odds, no-one likes a single point of failure. So my scenario requires:
Simultaneous false indicator on two sensors or
(Pilot does not select Idle) AND (cannot when alerted to it).
or something entirely different!
I guess that puts me back into the level of probability that we have chosen to accept.
Back in the corner now:)

SyEng 2nd Aug 2007 10:45

Memory action on no decel
 
Dear pilots,

No bites for my post 861 so here it is again:
---------------------------
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?

---------------------------

Is there a perception among (AB) pilots that once TR(s) are deployed, a go-around is not possible?

Bus14 2nd Aug 2007 11:08

"Is there a perception among (AB) pilots that once TR(s) are deployed, a go-around is not possible?"

No, but there is guidance for ALL commercial jet pilots that it is unwise to attempt a go-around after thrust reverser deployment in case one of the reversers fails to stow. This follows a fatal B737 accident many years ago. However, I have initiated a go-around from the runway in an A320. Like any other manoeuvre in the A320 it worked a treat, just like it should on any other aircraft, despite the sound advice not to try it. I am making no comment on the rest of the content of this thread other than to say that, as usual, most of it is uninformed rubbish. I have 12,000 hours in command on Airbus A320/321, in all weathers, and from long and short runways, and the aircraft never let me down. I have no idea what happened in this accident, and I suggest we all wait for the inquiry results (forlorn hope)

ABUKABOY 2nd Aug 2007 11:36

I'm a high-timer, but never flown FBW.......
 
We all know that the most energetically flown manual approach can sometimes be followed by a totally unexpected smoother-than-smooth touchdown on to standing water in (maybe) a howling crosswind. Even though it is not what was intended, and on an ordinary day on to a dry runway is a "landing to retire on", even so it happens, the water is not penetrated by the desired "firm" arrival, and the tyres aquaplane to a greater or lesser extent. Given that this aircraft never decelerated significantly, is it not just possible that the lightest of touchdowns (no WOW sensed, and maybe one mainleg at a time), plus significant aquaplaning which may not even have allowed the wheels to spin up, thus never triggered any/most of the logic conditions required to deploy any/all of the retarding devices OTHER than to allow reverse thrust?
Just my pen'worth, as this does not seem to have been considered thus far............

SyEng 2nd Aug 2007 11:48

Bus14,

Seems strange guidance given that the probability of one TR failing to stow must surely be much lower than the probability of a catastrophic outcome if the landing attempt is continued with after a "no spoilers" or "no decel" call (particularly on a short/wet runway). Unless I'm missing something (it has been known).

Where is this guidance published?

the_hawk 2nd Aug 2007 12:57


There are two Angle sensors on each Thrust Lever. If the two sensors disagree about the TLA, on the ground, but not at TOGA or FLX/MCT (i.e. take-off thrust setting), the FADEC selects Idle thrust irrespective of thrust lever position. An ECAM warning occurs and as part of the drill the pilot backs this up by selecting idle.
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)?

Mad (Flt) Scientist 2nd Aug 2007 13:22


Does anyone have an Idea why the system tries so hard not to deploy them? What would the opposite case be? Would a wing with all the panels up suffer structural overload apart from probably losing 80-90% lift?
The system tries so hard to not deploy GS until it KNOWS you are on the ground and attempting to stop (which is what all the logic looking for TL position and wheel spinup and WoW squat switches and the like is for) because the consequence of uncommanded GS (and FS on ground) deployment is potentially catastrophic.

If the GS were to, for some bizarre reason, deploy during TO (because the logic were set so as to 'ignore' TL position, say) then you'd be in serious trouble above V1 on a limiting runway.

And if they were to deploy early they would, as you suggest, destroy the vast bulk of the aircraft lift. landing gear are generally stressed to 10ft/sec impact velocity. In close to freefall (which is what 80-90% lift loss would imply) you'd get 10ft/sec if dropped from about 2ft! From, say, 10ft, you'd be so far above design loads for gear and supporting structure that the aircraft would be very, very, seriously damaged. Possible to write-off levels. Plus the attendant pax injuries, and if the wing tanks breach .....

Yet we need GS deployment to be prompt and reliable to get decent landing distances, especially on wet/slippery runways. So it's a fine balancing act to design a system which is ready to act on a hair trigger, but 'never' to act when it shouldn't. Hence the complex logic used for GS deployment (on all a/c, not just AB)

Johnbr 2nd Aug 2007 14:05

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????


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