Spanair accident at Madrid
Is there any way that we can convert this rumor of a video showing:
no engine fire,
a long takeoff roll
a drop back to the runway with a roll
as a fact
If so we can probably trim out quite a few speculations to date.
Unfortunately the thrust reverser questions will take some time to be disposed
no engine fire,
a long takeoff roll
a drop back to the runway with a roll
as a fact
If so we can probably trim out quite a few speculations to date.
Unfortunately the thrust reverser questions will take some time to be disposed
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I admit without reservation that the following is nothing more than considered speculation based on what I have read on these pages and what I have observed in similar cases in the simulator.
Aircraft has compressor stall left engine very close to VR. Witnesses report flames seen from left engine which are a characteristic of compressor stall. Reason for compressor stall unknown yet. Indications of compressor stall in cockpit may include hearing bang and slight yaw and some vibration. Vr is called and pilot (captain or first officer?) instinctively starts rotation then changes his mind and de-rotates. Someone pulls hard reverse on both engines as part of abort procedure. Probably gets reverse on right engine but possibly not on left engine depending if actual engine failure. Aircraft pulls right under influence of full reverse right engine and fatal delay in countering the right departure from runway centreline. Depending who was PF at the time, critical delay in handing over control to captain who presumably would have initiated abort process. Lack of good braking on grass or hard dirt verges extends stopping distance already compromised by abort action during rotation. Pure speculation of course but fits the reported track of aircraft.
Aircraft has compressor stall left engine very close to VR. Witnesses report flames seen from left engine which are a characteristic of compressor stall. Reason for compressor stall unknown yet. Indications of compressor stall in cockpit may include hearing bang and slight yaw and some vibration. Vr is called and pilot (captain or first officer?) instinctively starts rotation then changes his mind and de-rotates. Someone pulls hard reverse on both engines as part of abort procedure. Probably gets reverse on right engine but possibly not on left engine depending if actual engine failure. Aircraft pulls right under influence of full reverse right engine and fatal delay in countering the right departure from runway centreline. Depending who was PF at the time, critical delay in handing over control to captain who presumably would have initiated abort process. Lack of good braking on grass or hard dirt verges extends stopping distance already compromised by abort action during rotation. Pure speculation of course but fits the reported track of aircraft.
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Any number of airports the world over have significant obstacles alongside the runways, from terminal buildings to housing and roads, rivers etc..08 at LGW springs to mind as those terminal buildings and parked aircraft seem pretty damn close. Funchal perhaps?
Given the amount of fuel the aircraft would have had on board, and that it got airborne, then the likelyhood of the crash being survivable at all is very remote.
I am amazed that anyone survived; and we should be grateful for the small mercy that the only casualties were on board. At a lot of airports it could have been a very different story.
Given the amount of fuel the aircraft would have had on board, and that it got airborne, then the likelyhood of the crash being survivable at all is very remote.
I am amazed that anyone survived; and we should be grateful for the small mercy that the only casualties were on board. At a lot of airports it could have been a very different story.
Last edited by sussex2; 22nd Aug 2008 at 14:35.
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Is there any way that we can convert this rumor of a video showing:
no engine fire,
a long takeoff roll
a drop back to the runway with a roll
as a fact
If so we can probably trim out quite a few speculations to date.
Unfortunately the thrust reverser questions will take some time to be disposed
no engine fire,
a long takeoff roll
a drop back to the runway with a roll
as a fact
If so we can probably trim out quite a few speculations to date.
Unfortunately the thrust reverser questions will take some time to be disposed
El MD-82 despegó escaso de potencia y no se incendió en el aire, según las grabaciones - Nacional_Sucesos - Nacional - ABC.es
The images recorded by the cameras of security of the tracks of Barajas show that the MD-82 of Spanair that crashed Wednesday did not have sufficient power when initiated the takeoff, according to sources of the investigation consulted by ABC that already have visionado the sequence. It does not last more than two or three seconds. The image corroborates the testimony of the pilot of an airship that landed then in parallel: “That airplane does not take off, is eating the track”. As much he, as the rest of the crew of the airplane that came already from Guayaquil has been mentioned to declare by the Civil Guard. I collate of that recording, the marks left by the apparatus in the track - del wing, rest of the undercarriage, scattered to both sides, and the first successfully obtained testimonies, still without determining the causes, aim at that the accident took place of the following form.
The MD-82, with 162 passengers on board and ten crew, initiates the maneuver of takeoff to the 14,20 hours. It is the second attempt; almost one hour before a failure in the outer temperature sensor had had to return to the door of boarding when detecting the commander, that communicated to the passage. All the sources agree in which that anomaly does not have relation and so it happened later, but also it is being investigated. A technical inspector of Spanair certificó that McDonnell Douglas could fly. The manual anticipates that the switch takes off who gives energy him to the blower pipe, located under the cabin of the copilot, according to the company.
The airplane initiates the takeoff by track 36 left; the commander notices the lack of power, surely just after reaching the V1 call - when no longer the maneuver can be aborted; VR or turnover rate is arrived at. The aircraft, that had not risen more than 50 meters, inclines (probably after failing the right motor, although the doubts persist); one hurries to the ground, the right wing is striking the track and the pilot loses the control. The airplane to more than 280 km per hour is undone and crawling about 500 meters - there are marks of that uncontrolled maneuver. He does not arrive at the end of the track, leaves by the right, he crosses the peripheral fence and one hurries by a semislope staggered among five and seven meters until the channel of the stream of the Fertile valley. There the loaded deposits of kerosene explode and the apparatus catches fire. The dead and bodies alive are scattered in the lowest part of valley throughout about 400 meters. The crew did not get to put the undercarriage, went it leaving after falling to both sides of her route. “An established height does not exist to gather it. The normal thing is that the “train arrives” becomes ordained two or three seconds after the rotation, when already you have sufficient height and with a positive regime of ascent”, details a pilot to ABC. From a few approaches, everything is incognito. Who have seen the images yes assure that any motor is not appraised burning in the air, the lack power, the abrupt turn and the imbalance of the aircraft.
The little power can be due to multiple reasons: overweight, heating, failure of motor or one more a failure more serious than, in theory, must have detected in the revision of maintenance. “It surely raised to the front wheels and also the backs”, explained the minister of Promotion, Magdalena Alvarez. Sources of Civil Aviation draw attention on the failure of the motor: with the one nonoperative airplane it could have flown. They say that if that failure existed it had to take place after taking off, if the commander would not have aborted the maneuver. A human error is not discarded either. Nothing is it. Now the investigation, several parallels in fact, must be giving light all to these questions. The black boxes and the recording of security already are in the power of the Court number 11 of Madrid. One of the boxes is damaged, but the data will be able to be reclaimed equal. They are two: in one they are recorded the conversations of the members of the cabin and the outer control systems; second it is the technique, the one that operation of the motors, temperatures registers more of a hundred of parameters of the situation of the airship such as, pressures or atmospheric situation.
Collection of pieces and turbines Recovered after the wreck, they constitute one of the main probatory elements. The ones in charge to analyze them are the members of the Commission of Investigation of Accidents and Civil Aircraft incidents (Ciaiac), that depend on Promotion. Are seven civil servants, supported by personnel specialized in aerial security of the United States and the European Union and expert of the implied companies. To them he is incumbent on to them to explain all the technical part. They followed in “zone zero” picking up pieces, turbines and rest to label them yesterday and began to take the material to a room yielded in the airport. This investigation, longest in the time, comes together with other three: the corpse identification, the ocular inspection and the diligences. The team of Great Catastrophes of the Civil Guard, Scientific Police of the CNP and tens of forensic work without rest to conclude as soon as possible. The experts consider that by the traditional methods - tracks, photographic reconnaissance, identification of objects it will not be possible to put name to more than 60 or 70 victims, dice the state of the bodies; for the rest it will be necessary to resort to the DNA. The ocular inspection nothing else began to finish the rescue of victims. It has been entrusted to the central equipment of the Service of Criminology of the Civil Guard with support of his laboratories. Tens of agents are dedicated from Wednesday to take photographies in the zone, to determine the point of impact, to elaborate croquis, to mark the area in which they were scattered corpses, to separate properties, documentation, to resist each found rest. The police diligences have been ordered to the Judicial Police of the Command of Three Songs, supported by members of the Operative Central Unit. The agents will reflect in hundreds of folios the declaration of the wounded - still it has not been possible to take any; the one of the witnesses - they already are being located and being mentioned: the one of the personnel of the airport, personnel of the airline, technicians of maintenance, rescue teams. Puzzle of words to try to explain what it happened and how. The testimony of the survivors of the JK5022 will be key, whose flight plan was assigned the past to commander 17 of August. They will explain if she inquired to them into what happened, if a different maneuver were tried, if they noticed something. The last critical moment tens on agents and rescatadores lived yesterday. To 8,45 in the morning they recovered the cuerpecito burnout of a baby, covered by the weeds and the fuselage. To the 13 hours they found another minor, with the member amputees. They were those that lacked.
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Or indeed Jersey ... a 50m drop off the departure end of 27, and the old control tower/terminal building actually penetrates the 1:7 slope that's intended to protect against "untidy overshoots in IMC".
As with so many things in life, we have to start with where we are ... undoubtedly "it would be nice" to start with a blank sheet of paper [and an unlimited budget].
As with so many things in life, we have to start with where we are ... undoubtedly "it would be nice" to start with a blank sheet of paper [and an unlimited budget].
Re the apparent low-power take off; - the take off run appeared longer than normal.
Assuming that the TAT probe was the errant device; is TAT used in the calculation of thrust in the MD?
In some aircraft, TAT is used by the thrust management computer. If the TAT value is erroneously high, it can give a low thrust setting. The crew should cross check the demanded value with that required; if TAT is at fault, a manual value can be entered for computation or the required thrust level set manually.
This problem was often seen with non aspirated TAT probes which detected radiant energy from hot concrete surfaces.
Low power could contribute to low speed immediately after take off if normal pitch attitudes were used, i.e. attitude for the initial climb as opposed to speed, or before a speed schedule was reached.
Extending the speculation, then if the aircraft would not, or was judged that it could not continue to fly, then the landing should have been relatively ‘straight ahead’ (~ crosswind). However, if the low speed situation resulted in loss of directional control (wing drop) then a more severe veer-off might result in an ‘off airport’ landing.
Is the standard MEL practice for isolating the TAT probe via a breaker, if so what breakers are adjacent to TAT?
Assuming that the TAT probe was the errant device; is TAT used in the calculation of thrust in the MD?
In some aircraft, TAT is used by the thrust management computer. If the TAT value is erroneously high, it can give a low thrust setting. The crew should cross check the demanded value with that required; if TAT is at fault, a manual value can be entered for computation or the required thrust level set manually.
This problem was often seen with non aspirated TAT probes which detected radiant energy from hot concrete surfaces.
Low power could contribute to low speed immediately after take off if normal pitch attitudes were used, i.e. attitude for the initial climb as opposed to speed, or before a speed schedule was reached.
Extending the speculation, then if the aircraft would not, or was judged that it could not continue to fly, then the landing should have been relatively ‘straight ahead’ (~ crosswind). However, if the low speed situation resulted in loss of directional control (wing drop) then a more severe veer-off might result in an ‘off airport’ landing.
Is the standard MEL practice for isolating the TAT probe via a breaker, if so what breakers are adjacent to TAT?
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Poeple please.....
Guys,
please do not take the "too little power for takeoff" and takeoff roll longer than normal" too litterally. The plane took off, became airborne and dropped back to the ground, all in less than the length of the runway. In other words a normal (near) MTOW takeoff. That's all.
Takeoff roll longer than normal makes absolutely no sense and depends on so many variables. Remember that by default, runway analysis is based on letting the plane roll and gain speed on the ground as much as possible before getting airborne. An MD-82 near MTOW and using a balanced runway concept on this giant runway would have used a LOT of runway. Rotating at 747 speeds of 160 knots. I can't stress this enough.
Too little power during the takeoff roll means that the crew would have aborted as soon as you see that the engine(s) are not delivering the thrust required by the speed card. So be carefull how things are translated.
Xander
EDIT: To try and make it clear what I mean, look at this video of an MD-83 departing Valencia, Venezuela in 0 wind conditions with an elevation of 1400' and a temperature around 28° Celsius. Almost similar conditions.
This particular model is a HGW MD-83 with a MTOW of 72.6 tons i.s.o. 67.8 tons. This flight would have been close to 70 tons that day. Even with a static takeoff, the takeoff roll was still more than 40 seconds long.
Would it have crashed if an engines was lost? No, because it is calculated that you can takeoff in such conditions and that weight and those speeds. Beleive me, these procedures are not guesstimates. Also you can see how little flaps is used on this takeoff. That's around 7° of flaps.
YouTube - Despegue MD83 Insel Air
Hear those Pratts roar ! ! ! God I love it.
please do not take the "too little power for takeoff" and takeoff roll longer than normal" too litterally. The plane took off, became airborne and dropped back to the ground, all in less than the length of the runway. In other words a normal (near) MTOW takeoff. That's all.
Takeoff roll longer than normal makes absolutely no sense and depends on so many variables. Remember that by default, runway analysis is based on letting the plane roll and gain speed on the ground as much as possible before getting airborne. An MD-82 near MTOW and using a balanced runway concept on this giant runway would have used a LOT of runway. Rotating at 747 speeds of 160 knots. I can't stress this enough.
Too little power during the takeoff roll means that the crew would have aborted as soon as you see that the engine(s) are not delivering the thrust required by the speed card. So be carefull how things are translated.
Xander
EDIT: To try and make it clear what I mean, look at this video of an MD-83 departing Valencia, Venezuela in 0 wind conditions with an elevation of 1400' and a temperature around 28° Celsius. Almost similar conditions.
This particular model is a HGW MD-83 with a MTOW of 72.6 tons i.s.o. 67.8 tons. This flight would have been close to 70 tons that day. Even with a static takeoff, the takeoff roll was still more than 40 seconds long.
Would it have crashed if an engines was lost? No, because it is calculated that you can takeoff in such conditions and that weight and those speeds. Beleive me, these procedures are not guesstimates. Also you can see how little flaps is used on this takeoff. That's around 7° of flaps.
YouTube - Despegue MD83 Insel Air
Hear those Pratts roar ! ! ! God I love it.
Last edited by xkoote; 22nd Aug 2008 at 15:20.
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Airfield topography
Big Burd
Going the other way, off 09R, you would be into T4 even sooner and could be into BA Engineering if you went off the other way.
I agree a ravine between two runways is a bit extreme but how far out do you make everything flat? If this happened at LHR on 27L then you would end up in T5!
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BigBurd
"I agree a ravine between two runways is a bit extreme but how far out do you make everything flat? If this happened at LHR on 27L then you would end up in T5!"
I would say that you make everying flat as far as you can given the physical restraints imposed upon you. I appreciate that other airports have similar hazards too, and rather than that serve as an excuse for this accident, why can't this accident serve as a pointer to all those hazardous situations? If that means fixing Leeds-Bradford or the Bath Road, so be it (I'd like to see BAA's risk assesment for that).
The wording you find in many Airworthiness Directives "a hazardous situation has been found to that is likely to exist on similar types of aircraft . . ." generally goes on to mandate the spending of a lot of money by the airlines. Does a similar system apply to airports? - it should, they make enough money out of the airlines. How much money do you think airlines have spent on TCAS or 8.33 KHz FM separation or FM immunity or lockable flight deck doors or any number of other safety features addressing scenarios that are far less likely, or lethal, than a runway excursion?
The point is that this ravine is a risk to all other aircraft taking off or landing on both runways - should a future aircraft depart either runway, and we have to assume that one day one will, then the result will be similarly tragic. Avoidably tragic. The authorities, rightly, do not accept that sort of thing for technical faults on aircraft and issue ADs in response. Substituting this ravine with suitable drainage, infill and grading is a no brainer.
"I agree a ravine between two runways is a bit extreme but how far out do you make everything flat? If this happened at LHR on 27L then you would end up in T5!"
I would say that you make everying flat as far as you can given the physical restraints imposed upon you. I appreciate that other airports have similar hazards too, and rather than that serve as an excuse for this accident, why can't this accident serve as a pointer to all those hazardous situations? If that means fixing Leeds-Bradford or the Bath Road, so be it (I'd like to see BAA's risk assesment for that).
The wording you find in many Airworthiness Directives "a hazardous situation has been found to that is likely to exist on similar types of aircraft . . ." generally goes on to mandate the spending of a lot of money by the airlines. Does a similar system apply to airports? - it should, they make enough money out of the airlines. How much money do you think airlines have spent on TCAS or 8.33 KHz FM separation or FM immunity or lockable flight deck doors or any number of other safety features addressing scenarios that are far less likely, or lethal, than a runway excursion?
The point is that this ravine is a risk to all other aircraft taking off or landing on both runways - should a future aircraft depart either runway, and we have to assume that one day one will, then the result will be similarly tragic. Avoidably tragic. The authorities, rightly, do not accept that sort of thing for technical faults on aircraft and issue ADs in response. Substituting this ravine with suitable drainage, infill and grading is a no brainer.
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I think the T/Rev in the picture is sitting on burnt grass not tarmac.
Is the probe mentioned in previous posts heated by bleed air as the 767 is? (Bleed air too hot? )
..........and how do you quote a prev post?
Is the probe mentioned in previous posts heated by bleed air as the 767 is? (Bleed air too hot? )
..........and how do you quote a prev post?
Last edited by Desk Jockey; 22nd Aug 2008 at 15:32. Reason: Lack of experience on type.
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@ CLEE
Arguing against myself, in this specific case I could agree ... although presumably the Airport Operating Authority would then be looking for some fiscal support to justify spending on dramatically exceeding Internationally agreed norms 
However, the ravine is no more a risk than anything else [such as mentioned previously] that lies outside the Safeguarding Criteria. The idea is to protect aircraft operating normally. Where do you stop? or indeed, even start?
The point is that this ravine is a risk to all other aircraft taking off or landing on both runways - should a future aircraft depart either runway, and we have to assume that one day one will, then the result will be similarly tragic. Avoidably tragic. The authorities, rightly, do not accept that sort of thing for technical faults on aircraft and issue ADs in response. Substituting this ravine with suitable drainage, infill and grading is a no brainer.
However, the ravine is no more a risk than anything else [such as mentioned previously] that lies outside the Safeguarding Criteria. The idea is to protect aircraft operating normally. Where do you stop? or indeed, even start?
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Dear Lost in Saigon:
As you already know, the parallel runway is used in this case only for departures. So the pilot landing on paralell sounds unreal. Moreover, there is a testimony of a pilot who was waiting for the departure on the parallel runway and saw the accident, he told that the plane went to the air normally, then a sudden flash in the engine, unusual position of the nose up and then the fall to the right, the position of the nose kept his attention, although recognized that when seeing it from behind he may have been deceived by the perception.
How do you realize that the power at the moment of initiating the take off was not enough? Even though there are cameras, I read that they are far enough to get a fair picture of the plane, considering that the very clear and hot day didn´t help (I´d say like in the desert, you see mirages due to the very hot weather and the very clear surfaces)
I suspect that there may have exist more direct witnesses, as the surrounding area to the right is an elevation with full of houses, and I suppose someone else must have seen something else.
As you already know, the parallel runway is used in this case only for departures. So the pilot landing on paralell sounds unreal. Moreover, there is a testimony of a pilot who was waiting for the departure on the parallel runway and saw the accident, he told that the plane went to the air normally, then a sudden flash in the engine, unusual position of the nose up and then the fall to the right, the position of the nose kept his attention, although recognized that when seeing it from behind he may have been deceived by the perception.
How do you realize that the power at the moment of initiating the take off was not enough? Even though there are cameras, I read that they are far enough to get a fair picture of the plane, considering that the very clear and hot day didn´t help (I´d say like in the desert, you see mirages due to the very hot weather and the very clear surfaces)
I suspect that there may have exist more direct witnesses, as the surrounding area to the right is an elevation with full of houses, and I suppose someone else must have seen something else.
Last edited by agusaleale; 22nd Aug 2008 at 15:44.
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At many airports, where at ran off, it would be in a terminal - indeed, would be so at the other end of 36...
NoD
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Clee,
the CAA designated PSZ was changed about 10 years ago from a fan shape spreading out from the end of a runway to a triangle with its base extending either side of the centreline and coming to an apex as it extends from the end of the runway. For example LHR has a PSZ designation of both 27L and 27R which extend from a base 350m either side of centreline to an apex at 3.5Km.
Th PSZ is based on modelling of aircraft accidents since WW2 apparently - i.e. the further you get from the end of the runway the less likley you are to crash and, if you do, the more likley that you will be close to the centreline.
On this basis I would agree that within the perimeter there seems to be a very srong arguement that ground is free of non moveable obstacles which could potentially create a more dangerous situation for aircraft in an runway excursion. This would include large gullies and ravines.
The airport operators must undertake the risk assessment and should justify their decision not to undertake additional works that may be deemed reasonable. The cost is actually passed on to the users through airfield charges - so the passenger pays eventually!
Going back to LHR its not just Bath Road if you apply the Spanair circumstances to 09L you would find yourself either in the fireground or the Virgin, BM of BA hangar complex - not good!
the CAA designated PSZ was changed about 10 years ago from a fan shape spreading out from the end of a runway to a triangle with its base extending either side of the centreline and coming to an apex as it extends from the end of the runway. For example LHR has a PSZ designation of both 27L and 27R which extend from a base 350m either side of centreline to an apex at 3.5Km.
Th PSZ is based on modelling of aircraft accidents since WW2 apparently - i.e. the further you get from the end of the runway the less likley you are to crash and, if you do, the more likley that you will be close to the centreline.
On this basis I would agree that within the perimeter there seems to be a very srong arguement that ground is free of non moveable obstacles which could potentially create a more dangerous situation for aircraft in an runway excursion. This would include large gullies and ravines.
The airport operators must undertake the risk assessment and should justify their decision not to undertake additional works that may be deemed reasonable. The cost is actually passed on to the users through airfield charges - so the passenger pays eventually!
Going back to LHR its not just Bath Road if you apply the Spanair circumstances to 09L you would find yourself either in the fireground or the Virgin, BM of BA hangar complex - not good!
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["QUOTE"]
Does anyone have a crew list? I've only seen a passenger list.
["/QUOTE"]
Already posted, yes 30 pages to read...
Does anyone have a crew list? I've only seen a passenger list.
["/QUOTE"]
Already posted, yes 30 pages to read...
Last edited by Desk Jockey; 22nd Aug 2008 at 16:43. Reason: Unfair comment.
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Munnyspinner
Difficult without a picture ... does that triangle originate at the take-off threshold? or the departure end?
If the first, it just avoids the LHR terminals lying between the runways, but doesn't even reach the far end of 27 l/R..
If the second, the MAD quarry/ravine lies outside, as does everything and anything in between the parallel runways.
Innit?
the CAA designated PSZ was changed about 10 years ago from a fan shape spreading out from the end of a runway to a triangle with its base extending either side of the centreline and coming to an apex as it extends from the end of the runway. For example LHR has a PSZ designation of both 27L and 27R which extend from a base 350m either side of centreline to an apex at 3.5Km.
Th PSZ is based on modelling of aircraft accidents since WW2 apparently - i.e. the further you get from the end of the runway the less likley you are to crash and, if you do, the more likley that you will be close to the centreline.
On this basis I would agree that within the perimeter there seems to be a very srong arguement that ground is free of non moveable obstacles which could potentially create a more dangerous situation for aircraft in an runway excursion. This would include large gullies and ravines.
Th PSZ is based on modelling of aircraft accidents since WW2 apparently - i.e. the further you get from the end of the runway the less likley you are to crash and, if you do, the more likley that you will be close to the centreline.
On this basis I would agree that within the perimeter there seems to be a very srong arguement that ground is free of non moveable obstacles which could potentially create a more dangerous situation for aircraft in an runway excursion. This would include large gullies and ravines.
If the first, it just avoids the LHR terminals lying between the runways, but doesn't even reach the far end of 27 l/R..
If the second, the MAD quarry/ravine lies outside, as does everything and anything in between the parallel runways.
Innit?