Posts about: "Mayday" [Posts: 144 Pages: 8]

Suggests dual engine shutdown/rollback (VFGs offline) with auto RAT deployment.
Full length departure.
Aircraft flaps/slats extended.
Mayday broadcast.
This has a long way to go. I wouldn't be judging the Liveware until the data\x92s been analyzed in detail.

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.

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.

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

Obviously not confirmed but this is quite a prominent journalist in India reporting the words of the apparent mayday:

This was my thought. tf were they doing making a radio call in that situation.

I am not a pilot so apologies if this is a basic question.

Under what conditions will the RAT deploy? Is this automated or does the PF / PM need to hit a switch? <-- [Edit] I see this was largely answered in post 369. Thanks!

Watching the CCTV from the airport, it doesn't look like there was much time to do anything. I'm surprised someone called a Mayday (if that's true). And even to me, it seems pretty clear that bird never had enough power to go much of anywhere except where it did.

All so very tragic.

Are you familiar with balanced runway performance? Are you a heavy jet pilot? The rotation was normal. The aircraft definitely seems to have reached screen height. If so, it rotated at that position by design. It's initial climb seemed normal, notwithstanding it's duration, obviously until it stopped climbing..

Well, that's what one of the pilots reported in his mayday transmission.

You don't make a mayday call after mistakenly selecting flap 1

no way even with balanced engine performance you do not take off with no runway to spare you always leave some margin something was wrong from the start, whether that being flaps (which look like it from pics) or derated engine thrust. Something else may have happened, let\x92s see. Whatever the case that was not a normal take off roll

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 really want to know/hear what information was contained within the Mayday call. Unedited.

Lots of loony speculation on this thread from people I really hope are not qualified Pilots (or qualified ANYTHING for that matter). Thankfully the mods are doing an excellent job and weeding them out ASAP.

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.

I strongly agree with you. Fuel Cross feed valve is an example.

If you don't realize what you did, you might?

Would not be the first time that an accident has uncovered unintended consequences of a particular fallback configuration that was never able to be checked by either/any of Airbus, McDD or Boeing developmental test-pilots. Thinking of the automatic thrust augment/restoration on the MD81 (regn OY-KHO) that crashed 27Dec91 near Gottrora in Sweden (double engine failure). Design Boffins failed to realize that ice-sheet ingestion (sliding off the wings to be ingested by both rear-mount engines) would not benefit at all from each engine hiccup causing a continual uprating of the other (and vice-versa). To be found/uncovered in a simulator you would have to be testing various pilot inadvertencies (rather than rote expected actions). Then again, don't always believe the outcomes to be seen in a simulator. They don't necessarily faithfully emulate what would happen systems-wise in an aircraft... particularly when it comes to complex materiel failure modes or illogical sequiturs (e.g. MCAS)

So, if such an untestable circumstance were to happen to a competent crew and they were to inadvertently shut-down the wrong engine (and then/were in "clean-up mode":

a. The residual hyds would break the downlocks - but not retract the gear (and it would appear to be still selected down)
b. The alternate flaps might start to retract (gear downlocks not being now "made") once selected, but the slats remain out.
c. the RAT would deploy

The point at which all thrust ceases (and the climb vector flattens/reverses) is easily seen
in the video shot from the 6:30 clock position from about a km away. It's readily apparent.

An engine failure just off the runway after V1 in a fully loaded 787-8 in high ambient temperatures would assuredly have a crew thinking about a "toute suite" shutdown of a misbehaving donk. That's human nature. When the PERF is quite sluggish you will be thinking that a quick clean-up of the situation is certainly called for. That's just human nature unfortunately, particularly when you are under the time compression of dire circumstance (and the airframe is performing like a lame dog, just due to the environmentals and the early failure). I think that what the pilot reportedly said to ATC in his Mayday bears that out as being his instant mindset (quite clearly). Been in that "fools rush in" circ myself. You just have to "sit on your hands" and fly the beast.
But then again, if the RAT was NOT found deployed, then it's a case of the right seat mistakenly sucking in the flaps and slats... and that will do it... whatever the power/TOGA might be.
https://tinyurl.com/4zzkeeud
Rotation +33s
Mayday call +44s, circa 300 ft altitude (ADS-B)
Peak altitude +49s, 625 ft (Flightradar24)
Impact +58s, crash site 1.6 km from runway

Where are the details of the mayday call? Maybe I have just missed it.

I only saw the words quoted in one post, and I'm not sure that post looked factual.

Quite surprised there have been no recordings posted anywhere (even allowing for different lifestyles and hobbies)

Maybe you could point out where I judged anyone. Hint: I certainly did not. Also of course this is all speculation, what else? All I am saying is that the fact they decided to make a radio call while descending into a building could(!) be a useful sign about the state of mind of the pilots.That's it.

PS I am a senior widebody pilot with 30 years experience. Maybe start by refraining from judging me to set a good example ;-)

If tower is not looking a radio call would advise someone there is about to be a big issue and getting services notified asap giving best chance ? In this case it may of made little difference ?

Content of AI 787 pilot's distress call:
https://tinyurl.com/2ud2cdyn

https://tinyurl.com/yj58apka

Cannot relocate the actual recording - but it seemed to be a clear and unrushed statement per the above content cited at the two links