There is one known case where the crew had no indication whatsoever that they dealt with a #2 reverser deployment under similar circumstances, in an aircraft with a relatively comparable geometry, a Fokker 100, TAM Flt. 402, Oct. 31, 1996:


YouTube - TAM 402 de 1996 com legenda - transcrição caixa preta + FDR

Fokkerpilot.net - TAM 402 - CVR/FDR video. A must see!

What follows is a narrative of flt. 402:
Quote:
TAM flight 402 was a regular flight between São Paulo (CGH) and Rio de Janeiro (SDU). At 08:25 the flight received clearance for takeoff from runway 17R. Wind was given as 060 degrees. At 08:26:00 the throttles were advanced for takeoff power. Ten seconds later a double beep was heard. The captain said "O auto-throttle tá fora" and the copilot adjusted the throttles manually and informed the captain: "thrust check". With this information he confirmed that the take-off power had been adjusted and verified. Ar 08:26:19 the airplane accelerated through 80 kts. At 08:26:32 the copilot indicated "V one". Two seconds later the airplane rotated at a speed of 131 kts. At 08:26:36 the air/ground switch transited from "ground" "to "air". The speed was 136 kts and the airplane was climbing at an angle of 10 degrees. At that same moment a shock was felt and the EPR of engine nr. 2 dropped from 1.69 to 1.34, indicating the loss of power. In fact, the nr.2 engine thrust reverser had deployed. An eye witness confirmed to have seen at least two complete cycles of opening and closing of the nr.2 thrust reverser buckets during the flight. The loss of power on the right side caused the plane to roll to the right. The captain applied left rudder and left aileron to counteract the movement of the plane. The copilot advanced both thrust levers, but they retarted again almost immediately, causing the power of the nr.1 engine to drop to 1.328 EPR and engine nr. 2 to 1,133 EPR. Both crew members were preoccupied by the movement of the throttles and did not know that the thrust reverser on the nr.2 engine had deployed. The throttles were forced forward again. At 08:26:44 the captain ordered the autothrottle to be disengaged. One second later the nr.2 thrust lever retarted again and remained at idle for two seconds. The airspeed fell to 126 kts. At 08:26:48 the copilot announced that he had disengaged the autothrottles. He then jammed the nr. 2 thrust lever fully forward again. Both engines now reached 1,724 EPR. With the thrust reverser deployed, the airspeed declined at 2kts per second. At 08:26:55 the stick shaker activated, warning of an impeding stall. The airplane rolled to a 39 degree bank angle and the GPWS activated: "Don't sink!". Seven secons later the airplane impacted building and crashed into a heavily populated neighborhood."
Unquote

And this is the source:
ASN Aircraft accident Fokker 100 PT-MRK São Paulo, SP

Apparently there was no drift to the right until the aircraft became airborne. And please notice the flight control inputs in the simulation (based on CVR and FDR data) in an attempt to compensate for the yaw to the right. There are procedures in place on the Fo100 in case of a thrust reverser unlock situation, which can be managed if a reverser unlock light is presented. This crew (TAM 402) unfortunately did not receive any indications and were fighting the engaged AT before finally disengaging it. By then it was too late. Perhaps this crew never realized they were fighting a deployed #2 reverser because until the very end the copilot jammed the #2 thrust lever fully forward. . . . . .

Again, there is as yet no conclusive evidence this scenario fits the Spanair MD82, but it cannot be ruled out either until the facts are known.


Regards,
Green-dot

Let's not jump to conclusions if one of the T/R was deployed. The possibility exists that the crew deployed it after ground contact in an attempt to slow the a/c.

Several have mentioned about slow acceleration or apparent lack of power. Rananim is correct, hvy a/c, hot temps, optimum flap setting w/flex takeoff power can have completely different sense of acceleration vs. a lighter a/c taking off in cooler temps from a lower altitude.

Looking at the skid marks........

that unidentified mark starting in a position just outboard of the outboard of main wheel #4 is about the position a bucket would be at. It's incredible to see how it goes straight while the aircraft veers.

That combined with the fact that given the lack of scorched earth and the horror of watching that picture, together with the "damned" ravine makes me think how "relatively" better the outcome could have been for those involved. My heart just sinks and my insides churn at imagining how they had a chance..........unfortunately until that embankment reared it's ugly head. I feel so sad.........


Xander

two things we all have to agree upon:

low density air isn't what pilots say, we say high density altitude. that is the plane is performing as if it is taking off from a higher elevation.

2. thrust reversers, if the plane hit the ground and the pilot was holding on for dear life, he might have pulled the thrust reverser lever by accident.

what position was the landing gear in?

Regardless of all the operational and mechanical considerations, A340's posted link to the skid-marks gives us the completely definitive immediate cause of the disaster: the plunge into the ravine. The plane was on the main gear and given a longer flat overrun area it would presumably have come to a stop unharmed, with the proviso that we don't yet know if the right wing had touched the ground, and leaked fuel which caught fire before they went over the edge.

The area between the two runways should have been flattened and filled in and all overrun areas be kept clear as far as possible. If it is sensible for overrun areas to be longer, or at least for arrestor beds to be installed, then it must also be true of the areas to the side of the runways.

The area between the runways does nothing, has no purpose. It is entirely dead ground. The only thing it can do is destroy an aircraft that otherwise might survive veering off the runway. The terrain also prevents emergency vehicles reaching the scene. It is possible – although we cannot know yet for sure -- that more lives could have been saved if the tenders and the ambulances had been able to drive right up to the wreckage.

But that’s not the whole story. If you look at the Google earth pix you can see that the stream in the gully where the plane crashed has been channeled in a ditch around the end of 36L. Had they overrun in line with the take-off direction they aircraft would have been broken up by the river channel there, instead of in the ravine by the side of the runway. Just like the A340 at Toronto, MK 747 at Halifax, Kalitta 747 at Brussels, A320 at Warsaw, A320 at Cogonhas… the list goes on and on and on.

JM340. [IMG]http://i21.photobucket.com/albums/b270/cumpas/mad1.jpg[/IMG]

MD-82
 

I an interested in the theory that the flaps were not selected correctly for take-off. Does the MD-82 have a config warning to prevent this?

For how far out of interest? 100m? 500M 1KM?

Oh - and I presume whatever number you conjour up, we will have to clear all taxiways out that far as well - since a taxiing aircraft there would have caused the same result... :ugh:

The image above showing wheel marks alongside a runway cannot relate to the subject Spanair accident, not least because this is definitely not the same runway that was involved.

Most operators now leave the flaps and gear where they are (same for GPWS and windshear recovery) and call for 'Max Thrust' these days, at least on the Boeings and Airbuses I've flown in recent years. The additional flap call may be a legacy from Douglas or peculiar to the DC-9 variants.

'Firewall Thust' on older non-Fadec engines would have you push the throttles all the way up, possibly overboosting, overspeeding or overtemping the engines in an effort to save the aircraft. In newer engines pushing the throttles all the way to the stop gives you the maximum with appropriate limits so Firewall Thrust is the same as Max Thrust for a lot of us.

Sometimes you will have to do something to cancel a derate if you want Max Thrust after the throttles have declutched on the take off roll. The DC's I flew had human autothrottle so I'm not familiar with those new fangled twin engine DC models.

dba61 Are you serious? Please explain. :confused::confused:

A detail from the above photo of the ground-track:

http://i277.photobucket.com/albums/k...acksDetail.jpg

dba61 - The photo is from a series of 33 (quite poor) photos as per the link above. If it's not the same runway, could you please elaborate so these photos can be withdrawn if necessary? Tx.

dba51 Looks pretty like 36L to me ?

"Looks pretty like 36L to me ?"

NigelOnDraft

Are you saying that you personally recognise the area seen in the background of this photo (which is not T4, which would be further down at the far end of the runway to the left of the photo) comprising various airport buildings, aircraft and a town immediately behind up to the horizon?

All previous info indicated that the plane ended up in a ravine and there were some trees which it hit before going down there (as indicated by the ramp onlooker) but on this photo the tire tracks end up at some sort of an embankment. Does not quite match up huh?

dba61. You made a statement-

The image above showing wheel marks alongside a runway cannot relate to the subject Spanair accident, not least because this is definitely not the same runway that was involved.

Rather than quiz Nigel on Draft on what he may recognise at Madrid would you be kind enough to explain yourself? Thank you.

xolodenko, The 'embankment' is the edge of a ravine - which goes downwards. :bored:

@ Forget
thanks for the help with the image.

@dba61
Sadly, yes it´s Rwy 36L. The photo is taken from one of the rescue helicopters that responded to the crash. It appears to be over the crash site and looking at south west. You can even see T4 in the background with lots of IBE tails. Don´t mix up with T4S , wich is in between Rwy 36L/R and not visible in the photo.

JM

From where it started and other photos, I would dare to guess it was the no.2 engine. If it was, I would not expect the pilots to be able to deploy the TR before it came loose.

Bear in mind that the threshold of 18R is 81ft (25m) lower than the threshold of 18L
the threshold of 36R is 42ft (12m) lower than the threshold of 36L

there's still going to be a slope there.

Comparing the photo to the satellite pic, it sure looks like 36L, and matches the description given by an Iberia captain in a much earlier post

That was a severe swing to the right, and an equally quick correction. I would support the theory that the 'straight track' is the starboard reverse, possibly at high power until ?reduced? to correct the swing, or did its trail fade as perhaps the wings levelled? Equally, as Rainboe says, it could have been something 'hot and heavy' and detached. So, was it asymmetric reverse or the right wingtip drag that caused that dramatic swerve to the right?

It is now possible to tie down the exit point from examination of the R18 touchdown markers, and it would appear to me that the initial touchdown was off the runway and already angled well to the right.

I have tried zooming to max pixellation and cannot identify the debris between the wheel tracks and the runway. Is that part of an engine casing just right of mid-picture?