People are hanging onto false leads and not letting go. How do we know they didn't firewall the throttles? Moving flap would make no difference- they had crashed back before the flaps would have moved into position. Once you are in a stall situation, the only thing that is going to get you out of it is altitude and power. No clever techniques that might have worked on an overpowered naval fighter will do it.
Someone is hung up on the fact the flaps were deployed for the first take off. Well- it appears they did the after landing check and taxied back in with flaps retracted as they should. Then in the rush to leave for the second attempt, it appears the flaps were left retracted.
We really need some of the non-flyers in this thread to just watch and learn if they want to, and not try and come up with answers! 92 pages, most of it complete guff!
Quotes from the TWA Report (stick shaker on liftoff):
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There is no specific training for stall encounters immediately after liftoff from the runway.
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Based on their awareness of airspeed and flap configuration, the pilots should have concluded that the stickshaker was a false stall warning.
Related to this accident, "awareness of ... flap configuration" might be the key... However, in a system that is designed to check Takeoff Flap is correctly set on more than 1 occasion (? with us there is a check prior Taxi, and 2 checks in the "Pre-Takeoff checks") the crew cannot really be of any other mindset than the Flaps are correctly set...
Therefore the logic of the TWA Report, applied to this accident (and assuming the stick shaker did go off?) would be that the crew may well have, even should have, assumed it to be false.
Many posts ago, there were comments about the military method of timing the take off against distance travelled.
Sorry, just a humble Piper/Cessna type, but if the aircraft was clean, would it not have accelerated abnormally fast, and in an extra 500 metres ground roll it should have been well past Vr or even V2.
Sorry - cannot recall it, so either not read it, or dismissed in my mind as not really relevant, or too MD-80/DC-9 specific for me...
As Follows:
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Just thinking out loud and to ask for clarification from the experts. If the A/C thought it was flying because of a faulty WOW switch, would the TOCW still operate? If not, then the C/B issue is possibly a red herring?
It seems hard to believe however that such a simple problem could lead to such a disaster and there there is no redundancy inbuilt?
I tried timing and measuring the ground roll to 150 kts both flapless and with T/O flap/slat (we take-off in mid flap/full slat, which is also one of our landing configurations and is actually quite high drag - theory is to minimise ground roll and rely on reasonable excess power, and option to jettison in the event of engine failure, for initial climb) in the Tornado sim last week. The result support NoD's statement - there was negligible difference. Admittedly not an airliner, but operating using the same laws of physics!
Just thinking out loud and to ask for clarification from the experts. If the A/C thought it was flying because of a faulty WOW switch, would the TOCW still operate? If not, then the C/B issue is possibly a red herring?
It seems hard to believe however that such a simple problem could lead to such a disaster and there there is no redundancy inbuilt?
I did reply in fact
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Errrr.... If the Flaps were not set for takeoff, I am afraid there it is probably SOPs / Human Factors that led to the loss of the aircraft.
Things like TOWS are backstops that ideally should work, but it is difficult to attribute the (primary) cause of the accident to the TOWS not working. IMHO. A bit like blaming a faulty airbag for a road accident fatility... it would be better to avoid the accicent in the first place.
In short, if the takeoff was Flap/Slatless and the TOCW was not working, the accident was not "caused by" the TOCW, IMHO. It might be a "contributory cause" but if you have to reject a takeoff because the TOCW stops you, there should be a form of inquriy into just this... because the TOCW likely saved a lot of lives, and the rest of the "system" had failed.
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Admittedly not an airliner, but operating using the same laws of physics!
Not too sure about that - an airliner can get above 20,000'
Sorry if this has already been asked but let us assume that the TOW was inop would it not be in the T/O checklist to check the flap position indicator? the reason I ask is because some years ago I was the flight mech aboard an American trans air L1011 out of Philadelphia the check were down to the line and the check of the posn indicator was called and the flaps were set at 0 deg. we discovered that the hyd lock-out had activated and the flaps did not deploy even though the handle had been correctly positioned.
Hmmm ... now Spanair declares that, because both pilots left the cockpit for several hours, they were suppossed to check the TOWS alarms again for this flight.
And they said they did, according to Spanair. But they did it before the first return to gate.
I am sorry but I have never heard of that. As far as I know, the only TOWS check performed was at the first flight BCN-MAD.
@sevenstrokeroll
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the RAT probe being heated on the ground meant that the plane ''thought'' it was in the air. Pulling the RAT heater CB didn't do anything to the ground control relay etc. THE PLANE ALREADY THOUGHT IT WAS IN THE AIR and another CB didn't need to be pulled...
That is what I believe the more relevant to the accident. The famous P40 breaker at Detroit was pulled out due to "unknown reasons" The same cause wings1011 is talking about at the Lanzarote's "almost accident" and I believe something has to see at Madrid. Seems to me the P40 "the hand that rocks the cradle" is still ignored by the authorities.
Please also NB that a stick shaker on departure is an "interesting event". History might teach one to ignore the stick shaker and just fly the aircraft - see TWA Tristar @ JFK and even a recent VS747 incident. At a critical phase of flight, a stick shaker could be very distracting - and a good chance spurious. As above, you can only assume you are taking off with the correct performance and configuration.
History might also teach one to trust it, it's a system designed for a purpose... and at least one 'All Souls Lost' accident resulted from just that, ignoring it and even fighting the resulting 50lb stick push... Trident/LHR/Staines reservoir
Unless it is common knowledge specific to an aircraft type and situation that spurious s/s action can occur, aircraft mfrs and certificating authorities would take a very dim view of ignoring it. More so on 'T' tailed aircraft.
In this case, we could propose the following, admittedly hypothetical (as we don't know crew control inputs yet for sure) and assuming the most +ve outcome imaginable...
Stick-shaker noticed > Immediate reduction of stick back-pressure > Reduces AoA > Returns better roll-control > Prevents (2nd) bad roll to starboard > Aircraft stays more nearly on runway centreline > Crew have more options due less panic (compared to a/c diverging off-heading into unknown territory)
>> Possibly, whatever the outcome >> more people survive!
Because if the aircraft does prove to be correctly configured, and airspeed is correct, an immediate 'trial' reduction in AOA would not necessarily produce ground contact - and would increase margin speed over stick-shaker sensor speed, whether erroneous or not.
The first left-wing drop here was of course, a very strong indication that aircraft had been over-rotated (for speed/configuration) and needed flying 'gingerly' to retain control...
History might also teach one to trust it, it's a system designed for a purpose...
It's a balance. Read the NTSB L1011 report, it was fairly harsh on the crew for believing it and clearly stated (as above) they should have realised it was false.
First Officer was pretty well slated for doing exactly that. First Officer was not permitted to initiate an abort, but by relaxing on the back pressure he was deemed to have effectively aborted the takeoff after liftoff
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Because if the aircraft does prove to be correctly configured, and airspeed is correct, an immediate 'trial' reduction in AOA would not necessarily produce ground contact
It just about did in their case - certainly led to the illusion the aircraft would not fly... and the resulting overrun and hull loss.
It's a difficult call, as the report states... but as quoted above, there is no training in stall recoveries on liftoff, and very difficult to devise a drill that covers all situations...
Facts: zero flaps/slats take off attempt. Cnfig Warning did not work. Question: can FDR determine if the flap/slat lever was moved out of the "up" position? In other words has the possibility been ruled out already that the crew in fact could have set the flaps/slats correctly but that the flaps failed to operate followed by forgetting to check the FPI. In our company (I fly Avro) it is customary to check the correct setting by calling: FLAPS (NUMBER) (points to T/O datacard), SET (points to flap lever position) AND CHECKED (points to FPI).
Maybe slat deployment should be made fully automatic below some defined speed and/or above a certain AoA. The Tiger Moths I've flown have such slats over which the pilot has no control. I believe this design feature was included to protect student pilots from themselves.
If the slats were in the up position you can with the most certainly say the lever were in up position.This aircraft slat is controlled by a single drum dual actuator mechanism mounted in the aft center wing box section.This unit the is linked to each slat section with VERY thick control cables that via a simple solution with wires and pulleys from both sides actually pulling the the slat either in or out and they are all linked together unlike say a 737. Thats why no separate slat section indicator is needed like the 737.If one is going out ALL is going out if not a catastriophic failure accured to the cotrolcable system. That is highly highly unlikely though, basicly non existant if looking on how its constructed. The good thing of an old wires and pulley aircraft is that you can be very sure of the inputs done from cockpit actually is gonna happen in the back no matter what.It weighs but sure as hell. And that the wires from the leaver to the mid section of the aircraft should be broken off without any notice in feeling of flap handle is even that highly unlikly-Just basicly never happens
It is natural for pilots to try to think up a way to salvage a bad situation.
One suggestion in this accident thread is that perhaps lowering the nose to build airspeed in ground effect and/or select flaps might just have saved the day. Simulator trials by the investigation may well address that tactic, but achievable climb gradient is a major factor. Hitting an obstacle at high speed is a bad thing whether in the ground or in the air.
The bigger question is how a presumably well trained and conscientious crew missed this one.
First world air carriers do extremely well. That record perhaps breeds an expectation that you and your crew mates don't make mistakes while in fact you and they are people like anybody else who can screw up at unpredictable moments.
If this takeoff was Slat/Flapless, read the NW report - hardly able to climb, and very hard to control in roll...
