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-   -   Spanair accident at Madrid (https://www.pprune.org/rumours-news/339876-spanair-accident-madrid.html)

marchino61 26th Aug 2008 13:03

Translation of Spanish post above (to the best of my ability):


First I would like to express my condolences to all the families of the crew and pasengers. Rest in peace.

I was in ramp of the T-4s, at approximately 14:25, I saw how a Spanair MD took off and it caught my attention that it used a long distance to take off, almost equal to what the A-340 uses.

It lifted off almost at the end of the runway and was rolling to the left when it turned to the right and the wing touched the ground, after which the aeroplane dragged itself 500m, hit a grove of trees and exploded in a huge ball of flame.

At that moment my legs shook over what I had seen,(no daba credito) ,the thought that the plane was full of passengers was horrifying. I hope that my eyes never see anything like it again.

I feel disgusted about what is appearing in the newspapers - how can they publish that a pilot could fly if his plane was not in condition? putting his life and that of all the passengers in danger.

These comments embitter the families of the victims.

I am new in the web and i am sorry that my first comment is about a catastrophe at a Spanish airport.

My salutations to everyone.

xkoote 26th Aug 2008 13:22

I think the MD80 is one of the planes with the most amount of differering options out there. There's EFIS, non-EFIS, autobrakes or not, FMC's or not, switch locations on the overhead, TOW options etc etc. I have flown 4 MD-82's and one MD-83. 2 82's were the sisterships. One had a higher TO weight of 67.8 tons, but the units were in pounds. None had GPS-FMC's. The 4th -82 has the same TO weight of 67.8, but weights in kilo's and some switch positions wre different. The MD-83 is a HGW version which at one time was supposed to be delivered to the US military if memory serves me correct. Than planned didn't go through and there are a few out there. The have a TO weight of 72.6 tons and a MLW of 68.0 tons. That's 9 tons of extran landing weight than an -82. 5tons more than a normal -83.

The reason I say is that this plane may not have had an autobrake system. On the MD-82, the most prominent item being the RAT probe. It is the most obvious. Other than that, the cabin blower fans under the front cabin floor will stop operating. But only a lot of experience and a relaxed keen ear can detect that. If it was night time, you can also see the strobe lights flashing away on the wing tips. Other than that even though there's quite a list of inputs few may be aparent to crews. Remember also that the ground shift system abviously has a mechanical part and hydraulic part. It may be that for example that the landing gear anti retract knob which should retract when airborne, or the rudder controlled nosewheel steering which should be disconnected if the plane is in air mode, do operate as it should because electrecally the plane would thinks it's in the air, but mechanically (because the nose strut is still compressed) it is in gournd mode. I think these two systems are affected mechanically.

EDIT: If the taxi out checklist was carried out you would also have noticed that when carrying out the flight control check, the SPOILER DEPLOYED caution light fails to illuminate. In the check you verify that the light illuminates to confirm if your flight controls behave as they should. So if the checklist was carried out they should have noticed it.

Xander

sevenstrokeroll 26th Aug 2008 13:23

rananim

there is a button near the gear handle that is sticking out about an inch...press it and you override the ground shift mechanism and you can retract the gear on the ground

thinking it was in the air, this button would be flush with the instrument panel.

xantham above is quite right...we just don't know the exact configuration of this plane. indeed, former TWA ships had switches moving opposite direction to american airlines ships.

the RAT thing is really weird, you just don't see EPR settings that WRONG unless the plane is heating the RAT...and the only way it heats the RAT is when it thinks its airborne.

Now that the CVR thing is a phony, I stand by my theory

JM340 26th Aug 2008 13:24

skid marks photo
 
Look at this photo of the skid marks in the grass to the right of rwy 36L. Not being published before

Informativos Telecinco.com - Imgenes exclusivas de la tragedia - Galería de fotos

(sorry don't know how to put the image on the forum, is picture 1 of the gallery, if anyone can help on this please do so)

JM

enginefailure 26th Aug 2008 13:39

"Wouldn't a partially deployed or recycling thrust reverser (on one side only) explain the extra 500 meters of runway used before lifting off? If that is a plausible scenario, why was there no reverser light or warning indication on the flight deck? Apparently the crew had no notion of anything wrong with the aircraft during the take-off roll."


i am no professional pilot but:
if the right reverser would have deployed during take off run don't you think the crew would have realized that the plane drifts extremely to the right ?

sevenstrokeroll 26th Aug 2008 13:55

I think the thing that would get my attention if the reverser deployed would be the light that says reverser unlocked and rev ready

they are in front of your face, and if you can see the airspeed or horizon you would see these

the stall warning is a huge sign saying "stall", a profound HORN and a stick shaker, though no pusher. it can scare the hell out of you.

does anyone know if the plane pushed back or did a power back (reversed)?

justme69 26th Aug 2008 14:32

Spanish media speculates with the investigation concentrating in just about anything. Let's assume the plane stalled soon after leaving the ground, as the video tape and witnesses account seem to indicate.

Depending on what press you read/watch, even as today, still each claims the investigation is concentrating on one of different scenarios (pick your choice):

-Sudden engine failure. But there is no hard evidence on noises, fires, recovery procedures failing (full thrust on the other engine, etc), reliable witnesses, etc, prior to the airplane hitting the ground. Of course, it could've still happened and could be a likely cause, but shouldn't have been enough of a single cause to stall so early on and pilots not be able to recover. Also, doesn't quite fit the picture of the reportly somewhat long taxiing, etc.

-Others, on engine "lacking thrust". But surely crew felt it all seemed good enough to reach V1 and trusted it was enough to become airborne. Compressor(s) may have stalled etc, but likelihood of both engines failing to produce V2m after V1 w/o pilots being to do anything about it and no "loud" (i.e. explosion, etc) signs while still deciding to try to become airborne ...

-Others yet, on assymetrical reverser deployment. But the airplane showed no signs of difficult yaw/roll while on-ground, only shortly after it became airborne at enough height to roll both, to the left and to the right according to witnesses/survivors (pilot could probably over-recover, but still kind of unlikely) before the wing hitting the ground. Reverser seemed fully and properly deployed in at least one engine, but nobody has authoratively stated (some have, but never mentioned sources) that the second reverser was or was not deployed.

Still, having one or both reversers getting accidentally fully deployed, apparently after V1 but before V2, is a long strech. But it could've happened, of course.

Nonetheless, chances are that, once it became clear they were gonna crash, pilots probably tried to deploy them, but perhaps damage to the plane at that point or other factors (such as pilots being already injured from the first/second/third "fall" while bouncing around up to 6 times during about 500m before final explosion) made fully deploying succesfully only one of the reversers possible.

-Very few media is emphasising flaps/slats mistake or malfunction or speed/thrust gross miscalculations, coupled with alarms performance malfunction (i.e. plane thinking it was in air mode due to other sensors malfunction) or alarms de-activation (from earlier aborted T/O and/or repairs).

The likehood of this, I'll leave to each one of you to decide. How this could've happened w/o the pilots noticing on time, or the alarms failing to warn on time, or the pilots being unable to recover from stall on time, I'll also leave to each one of you to decide.

Let's remember this was likely a plane loaded on the heavy side, on lowish-density air and that it possibly did take some extra (grossly estimated) 500m than usual to become airborne and that it reportly hardly left ground-effect area with two (let's assume properly working) engines. There is some vague reporting on nearby witnesses thinking the "angle" of attack during roll was also "unusual" (i.e. either too steep or too shallow).

Many other scenarios are, of course, possible (sudden cargo imbalance, etc) or could've helped with the accident, but there is little hard evidence on just about anything other than the plane rolled and fell shortly after a T/O maneuver that looked to several witnesses (on video or survivors or external witnesses) like didn't have enough "power" to be completed successfully with no other apparent (visible or audible from the outside or the PAX inside) warnings.

Green-dot 26th Aug 2008 14:36


i am no professional pilot but:
if the right reverser would have deployed during take off run don't you think the crew would have realized that the plane drifts extremely to the right ?
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

misd-agin 26th Aug 2008 14:50

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.

xkoote 26th Aug 2008 15:08

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

sevenstrokeroll 26th Aug 2008 15:11

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?

Frangible 26th Aug 2008 15:15

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.

forget 26th Aug 2008 15:34

JM340.

(sorry don't know how to put the image on the forum, is picture 1 of the gallery, if anyone can help on this please do so)
[IMG]http://i21.photobucket.com/albums/b270/cumpas/mad1.jpg[/IMG]

Lodrun 26th Aug 2008 15:36

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?

NigelOnDraft 26th Aug 2008 15:38


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
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:

dba61 26th Aug 2008 15:47

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.

Airbubba 26th Aug 2008 15:50


I noticed that someone was talking about a "takeoff stall" recovery and said the call was "MAX THRUST"...we say "FIREWALL POWER" and or FIREWALL THRUST...SELECTING FLAPS 15...but if you already have flaps 15, that is just a confirmation . There is a difference between max and firewall in our lexicon.
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.

forget 26th Aug 2008 15:52

dba61

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

PJ2 26th Aug 2008 15:54

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.

NigelOnDraft 26th Aug 2008 15:56

dba51

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.
Looks pretty like 36L to me ?


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