Posts by user "sorvad" [Posts: 13 Total up-votes: 54 Pages: 1]

Originally Posted by Jonty

I disagree. I think the lines of the underneath of the aircraft are quite obvious and its clear there's no RAT. Given it drops on the wing to body fairing just behind the main landing gear on the starboard side of the aircraft, it should be very obvious in this photo.

Originally Posted by amsm01

(Sorry, Airbus here and not familiar with Boeing) Flap 5 to 1 reduction on the Boeing triggers autothrust reduction, is that correct? If so, are there any other conditions that need to be met for this to happen like being in some kind of takeoff mode? Just thinking whether this would have potential otherwise in other regimes to cause issues, discontinued approach perhaps.

Am slightly puzzled as to why if flap reduction triggering climb thrust is part of the standard logic (and presumably clean-up technique) then partial dual thrust loss wouldn’t be immediately recognised as the classic symptom of gear / flap retraction handling error? I presume Boeing pilots / air India are just as aware of this it as everyone else, strikes me as odd that one would immediately go into full dual EF mode. My instinctive reaction without knowing the Boeing would be to firewall both TLs, would this have worked in the early flap retraction logic scenario? Many thanks all

Originally Posted by Shep69

So for those getting in the weeds with one in several trillion (or lower) probabilities of systems failures have you considered that that improper RTOW (with or without improper flap setting), flap retraction / climb thrust trigger, is of much higher probability and has actually happened ?

Anyway I think we’ll find out soon if a systems failure was involved.

The FLCH Hold thing (Asiana) was never an issue and well known (at least on our line). And for a crew of 3 (or 4) to press a destabilized approach getting 40-ish knots too slow (!) isn’t a systems problem — it’s a breach of basic airmanship.

Originally Posted by StuntPilot

After hours of reading I conclude that so far nobody has the slightest clue about what happened.
1: Flaps were down
2: The RAT story is based on a single unsharp video frame. Earlier frames were much sharper but the RAT could not be seen (although there was a sound).
3. Lack of evidence

I could be wrong, in that case please link QUALITY evidence so that we can learn something new.
This way thousands of people are wasting countless hours.

Originally Posted by StuntPilot

We agree that there was a lack of thrust. Possibly caused by a dual engine failure. But the sharpest frames in the video do NOT show the RAT and this is counter evidence to the RAT theory. If there were substantial technical failures who knows what sounds could be generated. I find the evidence weak at best. And we immediately get into a chicken-egg problem: did some power issue of unknown nature cause an engine failure or did a dual engine failure occur, resulting in a power loss? Both are extremely unlikely and need to be backed by quality evidence. The video is not it, in my opinion. I don't know the APU intake mechanism and whether it could open after the impact.

Originally Posted by DIBO

I've been sitting on my hands for days now...but please stop linking RAT deployment evidence with some blurry cluster of pixelation, which proves nothing.
This Pprune-forensic audio analysis (and subsequent posts) by Kraftstoffvondesibel, although completely ignored by many it seems, is the only clear proof there was a deployed RAT sound recorded in the young boy's video clip. You may disprove the analysis as much as you like, but referring to blurry video regarding possible RAT deployment or not, is indeed " thousands of people are wasting countless hours "

I'm rather under the impression that many recent discussions are going backwards or h amsterwheeling.
But thank you for your valuable audio analysis

Originally Posted by Squawk7700

How could the CVR have been "read out" if the CVR hasn't yet been located?

This comment is from a low-budget news source.

Originally Posted by framer

There is a possibility that doesn\x92t get much air time on this forum that satisfies all the \x91facts\x92 ( pprune facts mind you), and requires less mental gymnastics to believe than many of the theories put forward. I\x92m not saying it\x92s what happened at all but it seems much more likely than a TCMA fault to me.
This link is to a Japanese report on a Jetstar 787-8 with GE engines that had both engines drop below idle while airborne due to magnesium salts effecting the operation of the FSV spools. The Magnesium salts came from a biocide dose by maintenance two days earlier.
For some reason I can\x92t paste the link but if you google JTSB the report number is AI2020-2.
I think it\x92s quite easy to imagine that a simple maintenance error ( 1000ppm instead of 100ppm) combined with extremely bad luck on timing lead to this accident.
I think I\x92m favouring a theory like this for its simplicity and the fact that fuel is the elephant in the room when you are dealing with a dual engine failure.

Originally Posted by Timmy Tomkins

If thre was a liquid invovlved, the rotation could be the trigger for a problem.

Originally Posted by sorvad

Water was mentioned earlier in the previous iteration of this thread, as I recall by one of the most well respected contributors on the forum and an expert in flight testing and certification issues. There have been a couple of well known incidents of flight deck screens going blank due to all sorts of electrical problems caused by water ingress into the E&E bay, fortunately in daytime vmc and not on particularly electric jets, and both I believe at rotation. The one I recall had it’s L1 door left open during a black rainstorm in Hong Kong. It’s also been said that total electrical failure can’t result in in a double engine failure on the 787, but I wonder what multiple sequelae could result from such water contamination with an aeroplane that relies so much on electrical power and software? Another very remote probability but many accidents and incidents are. I don’t even know if there was any inclement weather before this flight, maybe someone could confirm?

Originally Posted by nachtmusak

Non-aviation engineer here: I have a question about the low level altitude capture theory that I've been a bit hesitant to ask, since no-one else seemed to be bringing it up.

My understanding of altitude capture is that the autopilot will automatically adjust both thrust and pitch to intercept the requested altitude. However to my eyes there is very little pitch adjustment in the CCTV video of the plane taken from behind, until the very end of the video when it pitches up somewhat (obscured by buildings, more visible in the smartphone video). Please correct me if I'm wrong but I'd have thought that if the autopilot was trying to capture a very low altitude it would start pitching down (quite noticeably!) to do so, not remain at what looks like 10+ degrees nose-up. I honestly struggle to reconcile what I'm looking at in the video with an attempt to level off at 0ft, 200ft, or any of the other mentioned low-level altitudes.

Also maybe I'm missing something 787-specific but generally doesn't the autopilot have to be activated for the aircraft to automatically attempt to capture the pre-selected altitude? That was the case in this incident involving a Dash 8 and a target altitude of 0 feet that I am reading about ( https://www.gov.uk/aaib-reports/aaib...-dash-8-g-ecoe ). I'd have thought the PF would still be hand-flying the departure at the point that things went wrong, considering that the gear hadn't even been retracted yet...