Spanair accident at Madrid
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just a few thoughts
Before you regular posters attack me I want to point out I am a professional pilot but of the 737 classic? variety and have never flown any MD varient.
Once again, I refer to post 376.
It may well be a hoax (the poster never claimed it as his own) but it may also be genuine.
Many accounts say that the aircraft was veering to the right at an early stage. In the event of reduced but symmetrical thrust this would not happen until the stall.
I find it difficult to believe that an experienced pilot would not be able to control an engine failure, particularly in an aircraft with the engines so close to the centreline. I do take on board the points about atmospheric conditions and the possible discrepancy regarding pax weights.
In the SIM I have seen a heavy 737 get airborne with less than normal takeoff thrust get airborne at far less than normal speeds. eg Vlof <100kts.
Engines fail very rarely. The aircraft veered to the right.
In my opinion the rto will prove to be a red herring, although it is worth remebering that MEL items assume no other failures or combinations of failures.
It is only my opinion but I think an unlocked reverser is looking likely.
once again, just my own opinions
Once again, I refer to post 376.
It may well be a hoax (the poster never claimed it as his own) but it may also be genuine.
Many accounts say that the aircraft was veering to the right at an early stage. In the event of reduced but symmetrical thrust this would not happen until the stall.
I find it difficult to believe that an experienced pilot would not be able to control an engine failure, particularly in an aircraft with the engines so close to the centreline. I do take on board the points about atmospheric conditions and the possible discrepancy regarding pax weights.
In the SIM I have seen a heavy 737 get airborne with less than normal takeoff thrust get airborne at far less than normal speeds. eg Vlof <100kts.
Engines fail very rarely. The aircraft veered to the right.
In my opinion the rto will prove to be a red herring, although it is worth remebering that MEL items assume no other failures or combinations of failures.
It is only my opinion but I think an unlocked reverser is looking likely.
once again, just my own opinions
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More info on the reverser required!!!
777. Surely the L/E devices would've given a TO Config warning. And getting airborne early might be possible with mistaken lighter performance numbers, but in the ways of staggering into the sky, as has been described, surely a tail strike would have occured, if no slats, and or an early rotate.
Bummer bout the CVR/FDR.
Was there a heavy departure prior, 747 etc, which might have offered some dirty air in a no slats, lower than required speed departure.
And a flaming left and a reverser deployed on the right does give some evidence to the right turn prior to contacting the ground, unless as you say its been in a stall situation prior, or heaven forbid, stall caused from the reverser. If that was the case.
Bummer bout the CVR/FDR.
Was there a heavy departure prior, 747 etc, which might have offered some dirty air in a no slats, lower than required speed departure.
And a flaming left and a reverser deployed on the right does give some evidence to the right turn prior to contacting the ground, unless as you say its been in a stall situation prior, or heaven forbid, stall caused from the reverser. If that was the case.
I would like to ask the mods if they would make a sticky of the known facts of the investigation to save me wading through pages of conjecture
There are only facts that are believed to be known based on credibility of source and the experience of the interpreter to convey them.
The mods do not fit this bill.
Sorry but you are just going to have to wade through the stuff in this forum and decide for yourself what best represents credible fact according to your own experience.
I'll give you a clue some of the stuff here is "expert opininon" however much of it is wishfull theory
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Another crash survivor has died
The BBC is reporting that one of the survivors has died, bringing the total number of dead to 154. Unfortunately burns and burn or smoke damage to the lungs can be difficult to recover from and often prove fatal later, as here.
Birgenair????
Birgenair ALW301: probable Pitot static blockage, suspected to be from mud dauber wasps.
Spanair 5022: ?`
Now if you suggested that AeroPeru 603 was similar (not identical: pitot vs static bloackages) to Birgenair 301....
Now, it is possible for a pitot/static event to occur at any time, not just with wasps nesting or tape applied over static ports, AND a failure would be a high risk factor on a takeoff, and historically such failures tend to be problematic for crews to manage.... one assumes that the DFDR and QAR fitted to this type will ascertain that readily, as it records IAS from the DFDAU, and while GS is not recorded directly, the L/L will provided a derived GS (which is just nice to have to identify quantitatively IAS errors when corrected).
again, common issues are;outcome.
Please, await (avidly, if you must) the formal report conducted under Annex 13. If there is something new that is identified as a threat, then one assumes the authorities know their obligations under ICAO, and under EASA and EC law.
ref: http://www.flightsafety.org/ap/ap_oct99.pdf
AG RVS - News and Comment on the Aeroperu B757 Accident; AeroPeru Flight 603, 2 October 1996
Spanair 5022: ?`
Now if you suggested that AeroPeru 603 was similar (not identical: pitot vs static bloackages) to Birgenair 301....
Now, it is possible for a pitot/static event to occur at any time, not just with wasps nesting or tape applied over static ports, AND a failure would be a high risk factor on a takeoff, and historically such failures tend to be problematic for crews to manage.... one assumes that the DFDR and QAR fitted to this type will ascertain that readily, as it records IAS from the DFDAU, and while GS is not recorded directly, the L/L will provided a derived GS (which is just nice to have to identify quantitatively IAS errors when corrected).
again, common issues are;
- 3rd rock from sun,
- sad
Please, await (avidly, if you must) the formal report conducted under Annex 13. If there is something new that is identified as a threat, then one assumes the authorities know their obligations under ICAO, and under EASA and EC law.
ref: http://www.flightsafety.org/ap/ap_oct99.pdf
AG RVS - News and Comment on the Aeroperu B757 Accident; AeroPeru Flight 603, 2 October 1996
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Dand07, your post is grammatically and syntactically incorrect, then once one manages to read (interpret ?) it, you're insinuating a certain vested interest by pprune members that is neither clear nor likely.
Please refrain from wasting your and our time writing "under the influence" in the future.
Nicolai, not sure if you read this thread in full, but we're being given an update about survivors conditions few hours ago from someone citing spanish sources, by logic these should be more current than BBC, so in this case the sacred broadcaster is of no help.
Please refrain from wasting your and our time writing "under the influence" in the future.
Nicolai, not sure if you read this thread in full, but we're being given an update about survivors conditions few hours ago from someone citing spanish sources, by logic these should be more current than BBC, so in this case the sacred broadcaster is of no help.
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el #,
I've (re)read the whole thing and I didn't see anyone posting an update from any other source as to this (significant) change in status of casualties so I thought to put it up as a new piece of info, and I merely said "the BBC" to state my source; it's not a Spanish source because my Spanish isn't very good.
In this sort of news story, who gets the word out first can vary more with whether or not someone's sub-editor is on a teabreak
rather than who has the info first, since the news will travel very fast.
I've (re)read the whole thing and I didn't see anyone posting an update from any other source as to this (significant) change in status of casualties so I thought to put it up as a new piece of info, and I merely said "the BBC" to state my source; it's not a Spanish source because my Spanish isn't very good.
In this sort of news story, who gets the word out first can vary more with whether or not someone's sub-editor is on a teabreak
rather than who has the info first, since the news will travel very fast.
SLATS: 777fly, dash-27 et al
The configuration of the Slats (and flaps) will be a basic part of the initial investigation to verify. The system is well decribed in the MD-80 LAMM Section 27-85-00 page 101-103, including the auto slat behavior and warning systems.
quote reports unquote of possible lateral instability will certainly ensure some investigation is conducted in this area by competent investigating authorities.
As to CAWS: the 28v DC -L CB would need to be tripped, B1-832, AND the 28V DC-R CB B1-851 would need to be tripped for the crew to NOT get a warning of the CAWS being degraded/failed. (LAMM 31-51-00)
CVR will be interesting.
- The Slat position is recorded to DFDR/QAR via the DFDAU
- The cables may have witness marks to indicate position when tensile loads may cause separation of the cable
- The actuator will indicate the position of the Slat drive drum (27-81-1), as will the autoslat actuator MI 76/77 etc. As well, the Flap/Slat handle position will be identifiable
quote reports unquote of possible lateral instability will certainly ensure some investigation is conducted in this area by competent investigating authorities.
As to CAWS: the 28v DC -L CB would need to be tripped, B1-832, AND the 28V DC-R CB B1-851 would need to be tripped for the crew to NOT get a warning of the CAWS being degraded/failed. (LAMM 31-51-00)
CVR will be interesting.
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Nicolai, look at posts by 'justme69', #685 and #694.
I do not want to diminuish your contribution, but it's just that as you said, news circulate fast and someone invariably will report to pprune with expeditiousness.
I do not want to diminuish your contribution, but it's just that as you said, news circulate fast and someone invariably will report to pprune with expeditiousness.
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(apologies if it has already been posted)
Survivor describes wobble, crash, painful aftermath - CNN.com
"The airliner that crashed this week in Madrid had just barely got airborne and its right wing dipped sharply before the plane started wobbling and went down, one of the few survivors of the disaster said Saturday.
...
"But then it made a turn, as if the wing dropped abruptly," she said. "We were still very low, very close to the ground."
After the plane got a bit higher, it began to "wobble from side to side," she said, describing this as the last thing she remembers before the collision."
Survivor describes wobble, crash, painful aftermath - CNN.com
"The airliner that crashed this week in Madrid had just barely got airborne and its right wing dipped sharply before the plane started wobbling and went down, one of the few survivors of the disaster said Saturday.
...
"But then it made a turn, as if the wing dropped abruptly," she said. "We were still very low, very close to the ground."
After the plane got a bit higher, it began to "wobble from side to side," she said, describing this as the last thing she remembers before the collision."
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It seems at some point politicians were advised by two pilots "experts" who were allowed to watch the tape. A reporter writes about one of them saying: "It had to be a chain of errors ... a miriad of factors such as wind, bad cargo distribution or some external element such a large bird or a bad reaction from the pilots"
This expert is very puzzled that the plane (in the words of the reporter) "fell to the right when it would've been normal to fall to the left if the left engine was damaged" (as originally rumoured ... I don't know who came out with that rumor to begin with ...)
Both experts agree that it was very unlikely that the earlier fault that prompted the return to gate had anything significant to do with the direct cause of the accident.
But one of the two experts (I'm quoting the reporter now) "insisted that the accident could have originated due to an excess of weight in the plane and cited that as the most likely cause".
Ground airport personel at Spanair Barajas think that it's unlikely the airplane was grossly overloaded, but it was likely indeed either full, close to full or slightly over full capacity.
Once more, it's not fully clear how the airplane "fell" shortly after wheels left the ground. Seems it rolled a bit and fell, with one wing briefly touching the ground. Obviously at over max landing weight it could've sustained some damage from the "fall" and possibly injure pilots as well and start fires, etc.
My take on things: The plane was fully loaded, perhaps a bit over specs (but not necessarily). Some configuration was off-mark (either flaps or, more likely, slats). Enviromental conditions were not too good for sustenability (low air density, little but significant tail wind). Vr calculation was probably a bit short. Pilots unadvertenly used up a bit more runaway than usual without realizing something was off and then tried to take off a bit abruptly (your usual "if you want to go up, pull the wheel towards you"). For reasons unkown the plane stalled soon after ground effect was over w/o the pilots taking inmediate correction measures (perhaps they didn't have time as it rolled a bit much during stall for unknown reasons) or the engines failing to produce enough thrust and the plane hit the ground bouncing around for a while (perhaps accelerating after additional thrust was demanded a bit too late trying to complete take-off) sustaining damage (wing touching ground, landing gear over max. landing weight) or pilot injuries that led to lack of control, perhaps a decission to try to brake, and made it ultimately deviate to the right of the landing strip (wing hitting the ground damage could've produced assymetrical aileron configuration) and onto adjacent terrain where it finally crashed at high speed.
The plane rolling while airbone a bit too much could also be due to an assymetrical thrust situation (single engine failure or assymetrical reverser deployment, i.e.) rather than a random product of the stall in low density air or pilot action.
All of that, pure and baseless speculation of what could've happenned, but it's the mental picture I came out with while reading all the news about it here, in Spain. No idea how that could've happened, but it is what we've ambiguously been told by the media that happened so far.
This expert is very puzzled that the plane (in the words of the reporter) "fell to the right when it would've been normal to fall to the left if the left engine was damaged" (as originally rumoured ... I don't know who came out with that rumor to begin with ...)
Both experts agree that it was very unlikely that the earlier fault that prompted the return to gate had anything significant to do with the direct cause of the accident.
But one of the two experts (I'm quoting the reporter now) "insisted that the accident could have originated due to an excess of weight in the plane and cited that as the most likely cause".
Ground airport personel at Spanair Barajas think that it's unlikely the airplane was grossly overloaded, but it was likely indeed either full, close to full or slightly over full capacity.
Once more, it's not fully clear how the airplane "fell" shortly after wheels left the ground. Seems it rolled a bit and fell, with one wing briefly touching the ground. Obviously at over max landing weight it could've sustained some damage from the "fall" and possibly injure pilots as well and start fires, etc.
My take on things: The plane was fully loaded, perhaps a bit over specs (but not necessarily). Some configuration was off-mark (either flaps or, more likely, slats). Enviromental conditions were not too good for sustenability (low air density, little but significant tail wind). Vr calculation was probably a bit short. Pilots unadvertenly used up a bit more runaway than usual without realizing something was off and then tried to take off a bit abruptly (your usual "if you want to go up, pull the wheel towards you"). For reasons unkown the plane stalled soon after ground effect was over w/o the pilots taking inmediate correction measures (perhaps they didn't have time as it rolled a bit much during stall for unknown reasons) or the engines failing to produce enough thrust and the plane hit the ground bouncing around for a while (perhaps accelerating after additional thrust was demanded a bit too late trying to complete take-off) sustaining damage (wing touching ground, landing gear over max. landing weight) or pilot injuries that led to lack of control, perhaps a decission to try to brake, and made it ultimately deviate to the right of the landing strip (wing hitting the ground damage could've produced assymetrical aileron configuration) and onto adjacent terrain where it finally crashed at high speed.
The plane rolling while airbone a bit too much could also be due to an assymetrical thrust situation (single engine failure or assymetrical reverser deployment, i.e.) rather than a random product of the stall in low density air or pilot action.
All of that, pure and baseless speculation of what could've happenned, but it's the mental picture I came out with while reading all the news about it here, in Spain. No idea how that could've happened, but it is what we've ambiguously been told by the media that happened so far.
Last edited by justme69; 24th Aug 2008 at 02:53.
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This baffles me completely.....
This accident has left me for a loss for words. Here's why.
- If the RAT Probe heater fails in the ON position no light will illuminate in the cockpit. What did the captain mean?
- A RAt with an INOP heater and released due to favourable weather conditions is the same condition and terminlgy stated in it's MEL. So we'll take the mech for his word that the heater crapped out. In this case, especially on 29 degree Wx, no effect will be noticed and temps read correctly.
- Airplane stuck in air mode, with the plane not configure for takeoff? Could be, but then how can a pretty stiffly loaded MD82 roll dor takeoff, become airborne then crash back down all in less than a runways' length?
For an MD80 to become airborne with no slats in that condition requires at least 200 knots. Otherwise it will not fly, period. Maybe flaps less than prescribed? Should make that much difference if the slats are in the correct position.
- As I already said. If the plane had a problem being in airborne mode, MOST likely they can not retract the landing gear! This coupled with an engine failure MAY convence the crew to try and abort the TO. Maybe even as desperate as to deploy reverser as quickly as possible.
This scenario is all I can come up with. Many thoeries do not add up given the distance it travelled from brakes release for final resting place.
Xander
- If the RAT Probe heater fails in the ON position no light will illuminate in the cockpit. What did the captain mean?
- A RAt with an INOP heater and released due to favourable weather conditions is the same condition and terminlgy stated in it's MEL. So we'll take the mech for his word that the heater crapped out. In this case, especially on 29 degree Wx, no effect will be noticed and temps read correctly.
- Airplane stuck in air mode, with the plane not configure for takeoff? Could be, but then how can a pretty stiffly loaded MD82 roll dor takeoff, become airborne then crash back down all in less than a runways' length?
For an MD80 to become airborne with no slats in that condition requires at least 200 knots. Otherwise it will not fly, period. Maybe flaps less than prescribed? Should make that much difference if the slats are in the correct position.
- As I already said. If the plane had a problem being in airborne mode, MOST likely they can not retract the landing gear! This coupled with an engine failure MAY convence the crew to try and abort the TO. Maybe even as desperate as to deploy reverser as quickly as possible.
This scenario is all I can come up with. Many thoeries do not add up given the distance it travelled from brakes release for final resting place.
Xander
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Possibly Related (or a premmy flap/slat retraction in lieu of gear?)
At 0938 Central Standard Time on 2 August 2006, a Boeing Company 717-200 aircraft, registered VH-NXE, took off from Alice Springs Airport, NT, on a scheduled flight to Perth, WA.
The applicable aircraft take-off settings and techniques were applied by the flight crew for the takeoff. The recorded data showed that, 4 seconds after lift off, when about 31 ft above the runway, the aircraft's stall warning system activated for 4 seconds, and that the aircraft did not approach an aerodynamic stall condition at any time during the stick shaker activation. In response to the activation of the stick shaker, the flight crew increased engine thrust and reduced the aircraft's pitch attitude.
It is almost certain that an incorrect left wing slat sensor signal was received by the proximity sensing electronics unit (PSEU) from one of the two left wing slats proximity sensors. Consequently, the different slat position signals from the two sensors in the left wing resulted in the PSEU defaulting to the slats not-extended indication for the left wing. As a result of the different slat position signals sent by the proximity sensing electronics unit for the left wing (slats not-extended) and right wing (slats extended), the aircraft's flight control computers used the flaps-extended/slats-retracted stick shaker angle of attack schedule, leading to stick shaker activation and other stall indications.
Although no explanation could be found for the incorrect signal received by the PSEU from one of the two left wing slats proximity sensors, the aircraft manufacturer concluded that there did not appear to be a systemic problem in the worldwide 717 fleet.
Download complete report [508 KB PDF]
Premature flap (in lieu of gear) retraction. REPORT
The Crash of Northwest Airlines Flight 255 (MD82) at Detroit Metro - REPORT
The applicable aircraft take-off settings and techniques were applied by the flight crew for the takeoff. The recorded data showed that, 4 seconds after lift off, when about 31 ft above the runway, the aircraft's stall warning system activated for 4 seconds, and that the aircraft did not approach an aerodynamic stall condition at any time during the stick shaker activation. In response to the activation of the stick shaker, the flight crew increased engine thrust and reduced the aircraft's pitch attitude.
It is almost certain that an incorrect left wing slat sensor signal was received by the proximity sensing electronics unit (PSEU) from one of the two left wing slats proximity sensors. Consequently, the different slat position signals from the two sensors in the left wing resulted in the PSEU defaulting to the slats not-extended indication for the left wing. As a result of the different slat position signals sent by the proximity sensing electronics unit for the left wing (slats not-extended) and right wing (slats extended), the aircraft's flight control computers used the flaps-extended/slats-retracted stick shaker angle of attack schedule, leading to stick shaker activation and other stall indications.
Although no explanation could be found for the incorrect signal received by the PSEU from one of the two left wing slats proximity sensors, the aircraft manufacturer concluded that there did not appear to be a systemic problem in the worldwide 717 fleet.
Download complete report [508 KB PDF]
Premature flap (in lieu of gear) retraction. REPORT
The Crash of Northwest Airlines Flight 255 (MD82) at Detroit Metro - REPORT
Last edited by UNCTUOUS; 24th Aug 2008 at 03:30.
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Loose rivets - apologies. The only part of post 507 where I was addressing you was the first paragraph. At the time there was a whole load of posts - since deleted - making major suppositions, and the rest of that post was addressed to them. Sorry, I should have made it clearer.
I find it in bad taste to be nit-picking - in what is basically a technical discussion - about how many died, how many have been identified, and how many survivors are succumbing to their injurues or fighting for their lives, and who is right and who is wrong. Is this an ego contest ?
Unless you had a friend or relative on board - in which case you will be getting personal updates - what does it matter to anyone else ? It is sufficient to accept that this is a major disaster, with massive loss of life and in due course the correct figures will pass into historical statistics. QED.
Leave it alone.
Unless you had a friend or relative on board - in which case you will be getting personal updates - what does it matter to anyone else ? It is sufficient to accept that this is a major disaster, with massive loss of life and in due course the correct figures will pass into historical statistics. QED.
Leave it alone.
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Rewrote post 708 (in order to try and understand its ramifications)
ref the return to the ramp......
In the MD-82, the RAT probe sends temp data into the Air Data Computers.This data, in digital format, feeds both digital flight guidance computers.The DFGCs compute the EPR for each flight phase and for pilot selection through the TRP (thrust rating panel).The RAT probe is heated only in flight for anti-ice purpose. If, for some reason, the ground/air sensing relays (energized on the ground) change to an inflight condition, the RAT sensor is heated and the EPR is reduced. This change may be due to a circuit breaker opening (or a ground/flight sensor relay CB being left open by the mech after he deactivated the system? - shades of Helios?) or a ground/air sensor relay failing .This condition may affect the takeoff condition warning too. None of these prospective developments would be evident to the pilots.
.
The ART (automatic reserve thrust) is used only in normal T/O EPR. i.e. not in flex. or max. It's activated when the DFGC senses a difference of 30% between both N1 gauges. It's not an autothrottle function but carried out inside the fuel control unit. Its effective increase is about 700 lbs thrust or .05 EPR to the present thrust. The ATR ( auto thrust restoration) with the last DFGCs (-972 and subsequent ) is only active in noise reduction cutback procedures.
In the MD-82, the RAT probe sends temp data into the Air Data Computers.This data, in digital format, feeds both digital flight guidance computers.The DFGCs compute the EPR for each flight phase and for pilot selection through the TRP (thrust rating panel).The RAT probe is heated only in flight for anti-ice purpose. If, for some reason, the ground/air sensing relays (energized on the ground) change to an inflight condition, the RAT sensor is heated and the EPR is reduced. This change may be due to a circuit breaker opening (or a ground/flight sensor relay CB being left open by the mech after he deactivated the system? - shades of Helios?) or a ground/air sensor relay failing .This condition may affect the takeoff condition warning too. None of these prospective developments would be evident to the pilots.
.
The ART (automatic reserve thrust) is used only in normal T/O EPR. i.e. not in flex. or max. It's activated when the DFGC senses a difference of 30% between both N1 gauges. It's not an autothrottle function but carried out inside the fuel control unit. Its effective increase is about 700 lbs thrust or .05 EPR to the present thrust. The ATR ( auto thrust restoration) with the last DFGCs (-972 and subsequent ) is only active in noise reduction cutback procedures.
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Crashed plane's safety licence 'due to expire'
Dear Edward Owen "in Madrid" for the Telegraph,
may I suggest you refrain from writing about any technical issues to do with the accident. Putting your name to rubbish like this:
does nothing but add to confusion and display the ignorance of you and your editor.
may I suggest you refrain from writing about any technical issues to do with the accident. Putting your name to rubbish like this:
"El País reported that a pilot who landed half an hour before the crash informed Barajas control tower that the wind was "150-9" which meant from the south-east at nine knots. He hoped they would change the direction of takeoffs and landings accordingly since planes should take off into the wind and land with it."
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I cant understand why everyone is so puzzled about the roll off to the right. A classic manifestation of an incipient stall in ground effect and at high angles of attack is a kind of dutch roll (its not dutch roll). That means that the a/c would not be pointing along the centreline when it re-contacted the ground.
The "shuddering and side to side" motion described by survivors in Madrid is entirely consistent with a stall at high angle of attack and is identical to that described by survivors (or decryption of FDR tapes where there were no survivors) in MANY previous incidents. Sevenstrokeroll mentioned Detroit (DC-9-80, T/O configuration annunciator disabled, crew distraction, flaps/slats not set).
The yaw/roll degrades already insufficient lift (i've read by about 20%). The a/c just happened to be on a r/h yaw/roll when it returned to earth. If it had been on a l/h roll the survivability may have been very different.
Pinkman
The "shuddering and side to side" motion described by survivors in Madrid is entirely consistent with a stall at high angle of attack and is identical to that described by survivors (or decryption of FDR tapes where there were no survivors) in MANY previous incidents. Sevenstrokeroll mentioned Detroit (DC-9-80, T/O configuration annunciator disabled, crew distraction, flaps/slats not set).
The yaw/roll degrades already insufficient lift (i've read by about 20%). The a/c just happened to be on a r/h yaw/roll when it returned to earth. If it had been on a l/h roll the survivability may have been very different.
Pinkman
Last edited by Pinkman; 24th Aug 2008 at 08:05.
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how many meters/feet after the power application the Md80 should have rotate?
Does the pilot refer only to VR to rotate or should he/she have an approximate landmark for the rotation point? (I guess Yes)
My modest theory is that if the pilots did not RTO is because they were underpowered hoping to be able to get airborne anyway since the runway was so long.
then a combination of density altitude and faulty (perhaps) EPR temp air data made such tragic cocktail .
what do you think?
then: "two decades of fear" Since I was flying the 737-100 I was always afraid of un-commanded deployment in flight. is in that old reverser design the Clamshell kept closed by sort of springs? if there is not hydraulic pressure could a reverser fall open by the air stream (is like a metallic parachute). Many Biz jet still use this old clamshell design..
Does the pilot refer only to VR to rotate or should he/she have an approximate landmark for the rotation point? (I guess Yes)
My modest theory is that if the pilots did not RTO is because they were underpowered hoping to be able to get airborne anyway since the runway was so long.
then a combination of density altitude and faulty (perhaps) EPR temp air data made such tragic cocktail .
what do you think?
then: "two decades of fear" Since I was flying the 737-100 I was always afraid of un-commanded deployment in flight. is in that old reverser design the Clamshell kept closed by sort of springs? if there is not hydraulic pressure could a reverser fall open by the air stream (is like a metallic parachute). Many Biz jet still use this old clamshell design..
