Posts about: "Flaps (All)" [Posts: 165 Pages: 9]

Arrowhead
2025-06-12T14:43:00
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Post: 11899284
https://www.flightglobal.com/probe-d...121461.article

No idea what happens to a Dreamliner, but the A320 series can handle flaps instead of gear retraction

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Chesty Morgan
2025-06-12T14:53:00
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Post: 11899296
Originally Posted by Propellerhead
It\x92s obviously producing plenty of thrust as it rotates from the dust. It would take longer than that for the aircraft to lose lift if the flaps were retracted instead of the gear. It take a while for them to run.
The loss of lift would begin immediately.

It looks like they used up an awful lot of runway so potentially incorrect performance and thrust setting, incorrect flap setting, chuck in a temperature inversion or changing winds too if you like and mistakenly retracting flaps instead of the gear could well be the last orifice of the Emmental.

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ManaAdaSystem
2025-06-12T14:59:00
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Post: 11899300
A mayday call will normally contain information about the nature of the emergency.
The flaps instead of gear is based on the landing gear being down throughout the whole emergency. It\x92s just weird. I get that it may be overlooked in a stressful situation, but when they had time for a mayday call?
So, someone said the 747 will have an early thrust reduction if you retract flaps too early, is this also the case with the 787?
Maltese Falcon
2025-06-12T15:02:00
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Post: 11899305
It was mentioned before but needs mentioning again. If, as reported, a MAYDAY was issued, I think we can discount the "incorrect flap setting" and 'inadvertent flap retraction" theories. A MAYDAY call is an appropriate response to mechanical failure/bird strike etc but generally not what pops into the mind when you realise your pilot error is about to result in a crash.

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KSINGH
2025-06-12T15:02:00
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Post: 11899306
Originally Posted by Propellerhead
Aerodynamically it would fit with taking off without flaps - normal rotation and climb until clear of ground effect at around 200ft at which point the lift would drop a lot. It\x92s not a single engine failure as no sign of yaw.
hasn\x92t every jet had a take off configuration warning for about 30 years now? Surely the 787 has something far more advanced than that (electronic checklists) as well as airlines having various SOPs to catch that. Retracting flaps instead of gear is plausible (but as I said above doesn\x92t really align with the apparent mayday call they got out) but taking off with zero flaps would be unthinkable for anything as modern as a Dreamliner surely
Chesty Morgan
2025-06-12T15:04:00
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Post: 11899310
Originally Posted by KSINGH
hasn\x92t every jet had a take off configuration warning for about 30 years now? Surely the 787 has something far more advanced than that (electronic checklists) as well as airlines having various SOPs to catch that. Retracting flaps instead of gear is plausible (but as I said above doesn\x92t really align with the apparent mayday call they got out) but taking off with zero flaps would be unthinkable for anything as modern as a Dreamliner surely
Mayday call could just be a panicked reaction to not having a clue what was happening.

12 users liked this post.

CurlyB
2025-06-12T15:20:00
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Post: 11899328
Originally Posted by Arrowhead
https://www.flightglobal.com/probe-d...121461.article

No idea what happens to a Dreamliner, but the A320 series can handle flaps instead of gear retraction
Except here it's 40\xb0C SAT

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ahmetdouas
2025-06-12T15:25:00
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Post: 11899336
Originally Posted by Chesty Morgan
The loss of lift would begin immediately.

It looks like they used up an awful lot of runway so potentially incorrect performance and thrust setting, incorrect flap setting, chuck in a temperature inversion or changing winds too if you like and mistakenly retracting flaps instead of the gear could well be the last orifice of the Emmental.
Agree 10000% this is what I feel the most likely thing is. No indication of engine failure, no indication of bird strike, no indication of Ram Air deployed (would it even have time to deploy? The plane crashed like 30 seconds after take off) The take off run was way long, low power/flaps misconfig. I think we will find the reason out very quickly.

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whatdoesthisbuttondo
2025-06-12T15:36:00
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Post: 11899358
Originally Posted by nachtmusak
I don't really understand why so many people have latched so hard onto the theory that the flaps were not extended based off nothing but a poor quality video (while also ignoring other clues in that same video, such as what is almost certainly the sound of a ram air turbine - never mind that even in that video you can equally conclude that the slats and flaps are extended).

One would think it sensible to at least wait for higher quality images/video to emerge before saying it with confidence, given how incredible the claim and aspersions being cast on the crews' basic competence and professionalism are.
It looks like an action slip to me as the timing looks right ie \x93positive rate \x93 \x93gear up\x94 (someone raises the flaps instead of the gear) PF is looking through the HUD so just sees someone move their hand rather than the hand moving the correct lever

It\x92s then taking off heavy weight with 35c and the flaps have been raised and the gear is still down.

As nobody realised the flaps had been raised instead of the gear when it happened they automatically think it\x92s some other issue as the aircraft loses lift and the amber band rapidly rises and the aircraft runs out of lift.

could be something else like fuel or 2 engine failure but seems possible it\x92s an action slip also.

I didn\x92t see the RAT deployed but saw the gear down still and an aircraft fall out of the sky with what sounded like engines running still.

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Damonjames
2025-06-12T15:44:00
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Post: 11899374
Ive been away from aviation a while now, but the level of information available almost immediately after drew me back in here.

Genuinely looks as though (as propellorhead has stated) it comes out of ground effect without enough lift to climb any further. I suspect high temperature, QNH and heavy load will all have played a factor, and maybe flap setting may have been insufficient on this occasion. Sad situation.
nachtmusak
2025-06-12T15:54:00
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Post: 11899393
Originally Posted by whatdoesthisbuttondo
It looks like an action slip to me as the timing looks right ie \x93positive rate \x93 \x93gear up\x94 (someone raises the flaps instead of the gear) PF is looking through the HUD so just sees someone move their hand rather than the hand moving the correct lever
In the high-def photo of the wing post-crash that has been posted in this thread, the flaps are visibly extended.

Also, unless we are all watching very different videos, I don't quite understand how anyone cannot hear the propeller buzzing in the video of the plane passing overhead. It's quite distinct. Though of course in this new age of AI we should take any and all audio/video with a grain of salt - which is exactly why confidence that the flaps are or aren't retracted based on such low-quality footage is a bit silly to me.

1 user liked this post.

KSINGH
2025-06-12T16:33:00
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Post: 11899447
This appears to be the slats out at least:

is it possible to set slats only for take off on the 787/boeing? For the Airbus we will get 1(slats)+F (flap) on the ground when selecting flap position 1
fdr
2025-06-12T17:07:00
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Post: 11899492
Originally Posted by Gurnard
"Minutes after taking off"?? Surely the crash was within less than a minute,
The video from the NE end of the runway, beside the RVR sensor shows a liftoff occurs abeam the closed high speed taxiway between C and D. Thats at 1250m to run to the DER. The first 10 seconds of flight is steady, and then the aircraft stops climbing and starts a gentle descent, and 5 seconds later the pitch starts to increase in 2 stages with impact around 20 seconds after liftoff. This is not the ADSB data, it is the video at the boundary on F/B.

The video take from the south end of the airport appears to show the RAT deployed.

The flight VAAH-EGLL is not a particularly heavy departure, the takeoff distance is not unreasonable for a twin jet, at under 7,000' from brakes release. I have limited developmental time only on the 787 before EIS, and I cannot recall any surprising latent threat in the performance of the aircraft for a premature flap retraction, and that certainly would not result in a RAT deployment. An accidental ATR low level off capture might get exciting for a few seconds, but it would not result in a RAT either.

The seat 11A pax survivor is remarkable.

6 users liked this post.

JG1
2025-06-12T17:19:00
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Post: 11899499
Looking at the video of the takeoff roll, it seemed normal, normal rotation, normal initial climb. Other incidents with incorrect performance data or incorrect flap setting (especially flapless) resulted in an extended rotation phase, often with a tailstrike which doesn't seem to be the case here. So the flaps were probably set correctly.

This aircraft then climbed okay but then 3 things happened

1. They didn't raise the gear (maybe due distraction)
2. They apparently called a mayday for an engine problem
3. The aircraft started to sink and continued to do so until ground impact

The videos and the flight path don't seem to show lateral deviation or rudder application but if they called mayday for an engine problem we've got to go with that.

Perhaps the flaps were retracted early but I don't see any pitch change, just sink.

As the aircraft is certified to fly on a single engine, it should have done so. That it didn't seems to indicate that the other engine also stopped developing the required thrust.

Whether it was shut down unintentionally or damaged due to some environmental factor remains to be seen but my moneys on inadvertent shutdown.
tinshifter
2025-06-12T18:03:00
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Post: 11899551
I think it may be a simple case of inaccurate takeoff performance data, or inadvertent retraction of flaps instead of gear (this can happen and does happen).

I'm no expert and open to discussion, but it looks to me like the slats are somewhat extended but the flaps weren't, or at least not from the angles we have seen so far. The autogap system on the B787 will automatically extend the slats if they are already in the middle position (i.e Flaps 1) with KIAS <225. Perhaps, either the inaccurate input for takeoff performance produced figures that allowed a Flaps 1 departure, leading to a longer takeoff roll and then once out of ground effect, insufficient climb gradient and a pilot induced stall. Alternatively, at the point where you would likely ask for gear up, the PM has inadvertently selected Flaps 1 from Flaps 5 leading to the same effect. Pilots experienced startle and shock, declared a Mayday as they knew they were descending when they shouldn't be and didn't have time to appropriately react.

Dual engine failure is obviously a possibilty however rare it might be. but it doesn't look like any catastrophic failure from the video. Clearly a sad day for all in aviation and looking forward to the official investigation and results, hopefully something we can all learn from.

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ahmetdouas
2025-06-12T18:05:00
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Post: 11899553
Originally Posted by JG1
Looking at the video of the takeoff roll, it seemed normal, normal rotation, normal initial climb. Other incidents with incorrect performance data or incorrect flap setting (especially flapless) resulted in an extended rotation phase, often with a tailstrike which doesn't seem to be the case here. So the flaps were probably set correctly.

This aircraft then climbed okay but then 3 things happened

1. They didn't raise the gear (maybe due distraction)
2. They apparently called a mayday for an engine problem
3. The aircraft started to sink and continued to do so until ground impact

The videos and the flight path don't seem to show lateral deviation or rudder application but if they called mayday for an engine problem we've got to go with that.

Perhaps the flaps were retracted early but I don't see any pitch change, just sink.

As the aircraft is certified to fly on a single engine, it should have done so. That it didn't seems to indicate that the other engine also stopped developing the required thrust.

Whether it was shut down unintentionally or damaged due to some environmental factor remains to be seen but my moneys on inadvertent shutdown.
nothing was normal the plane rotated right at the end of the runway far too late and barely climbed at all for 10 seconds before falling 20 seconds and finally crashing 30 seconds after take off.

The most obvious answer is low power/flaps setting if the engines were weird they would have probably aborted take off. Bird strike/engine issue during take off roll after v1? Super unlikely but never say never
YRP
2025-06-12T18:42:00
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Post: 11899587
Originally Posted by ManaAdaSystem
A mayday call will normally contain information about the nature of the emergency.
The flaps instead of gear is based on the landing gear being down throughout the whole emergency. It\x92s just weird. I get that it may be overlooked in a stressful situation, but when they had time for a mayday call?
So, someone said the 747 will have an early thrust reduction if you retract flaps too early, is this also the case with the 787?
This was my thought. tf were they doing making a radio call in that situation.
AndrewW
2025-06-12T20:23:00
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Post: 11899693
The theories concerning inadvertent flap retraction are not consistent with the apparent transcript from the mayday call made or rat deployment. In the first video that circulated, the engines can\x92t really be heard (certainly not producing any significant amount of thrust). If the aircraft was climbing out misconfigured, those engines would be screaming. Instead, all you can hear is the rat.

Similarly - a bird strike, knocking out two engines simultaneously is a noisy/messy event and I would expect to see evidence of this occurring in both videos, and in the area at the point of ingestion. The engines don\x92t just roll back with a bird strike - they surge, smoke, bang and splutter. It would be very apparent.

At this time, I think everything is pointing towards both engines simultaneously having their fuel feeds interrupted between V1 and Vr. CVR/FDR will be interesting.

7 users liked this post.

FL370 Officeboy
2025-06-12T20:42:00
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Post: 11899714
Originally Posted by AndrewW
The theories concerning inadvertent flap retraction are not consistent with the apparent transcript from the mayday call made or rat deployment. In the first video that circulated, the engines can\x92t really be heard (certainly not producing any significant amount of thrust). If the aircraft was climbing out misconfigured, those engines would be screaming. Instead, all you can hear is the rat.

Similarly - a bird strike, knocking out two engines simultaneously is a noisy/messy event and I would expect to see evidence of this occurring in both videos, and in the area at the point of ingestion. The engines don\x92t just roll back with a bird strike - they surge, smoke, bang and splutter. It would be very apparent.

At this time, I think everything is pointing towards both engines simultaneously having their fuel feeds interrupted between V1 and Vr. CVR/FDR will be interesting.
The issue I have with the \x91mis-selected flaps up\x92 theory is that if PM had accidentally retracted flaps, I\x92d expect the PF to lower the nose, apply max thrust to try and accelerate by flying level or in a minimal descent. In this accident, the nose never seems to get lowered to decrease the AoA, in fact pitch increases just before it seems to stall. I\x92d also expect similar for an overweight takeoff, thrust or loadsheet error.

The fact none of the above happened, coupled with the lack of landing gear coming up, makes me think they didn\x92t have thrust to play with.

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ILS27LEFT
2025-06-12T20:46:00
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Post: 11899718
Originally Posted by AndrewW
The theories concerning inadvertent flap retraction are not consistent with the apparent transcript from the mayday call made or rat deployment. In the first video that circulated, the engines can\x92t really be heard (certainly not producing any significant amount of thrust). If the aircraft was climbing out misconfigured, those engines would be screaming. Instead, all you can hear is the rat.

Similarly - a bird strike, knocking out two engines simultaneously is a noisy/messy event and I would expect to see evidence of this occurring in both videos, and in the area at the point of ingestion. The engines don\x92t just roll back with a bird strike - they surge, smoke, bang and splutter. It would be very apparent.

At this time, I think everything is pointing towards both engines simultaneously having their fuel feeds interrupted between V1 and Vr. CVR/FDR will be interesting.
I strongly agree with you. Fuel Cross feed valve is an example.

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