Posts about: "TOGA" [Posts: 63 Pages: 4]

And PF's reaction being to pull back and stall into the ground rather than lower the nose, select TOGA and call for gear up (or do it himself)....

For an aircraft that will likely have TOGA pressed and be at a high power setting (plus the RAT deployed) it sounds awfully quiet.
Perhaps the gear was down because they knew they were going to force land due to lack of thrust.
(Only a 738 driver), but the electric pumps to drive the hydraulics is much slower than the engine driven pumps and so flap selection / re-selection could be not as expected.

RIP to all involved.

787 gear and flaps/slats are both on the centre system, powered by 2x big electric pumps and no EDPs, so retraction should be minimally impacted by engine failure assuming electric power was still available and reconfiguration worked. Note the 787 has two generators per engine so generator failure is also unlikely to contribute, unless both engines failed taking out all four generators (and presumably no APU running).

From that thread, I believe it was discussed that on most/all other large transports, deploying the RAT re-powers the CVR/FDR. The 737 didn't have that happen because no RAT. You may still get a few second gap while the RAT deploys.

The 787 has 2x Enhanced Airborne Flight Recorders (EAFR), which each record both cockpit voice and flight data. I expect they are also fitted with the dedicated batteries that the Jeju was a year or two too early to require. Per the NTSB , the forward recorder has a 10-minute backup battery.

Hopefully flight data is not going to be an issue for this investigation.

The suggestion is that the buzzsaw/propeller sound is the RAT; it does sound a bit like an interference pattern, but you don't get the engine roar with it.

It's also maybe visible in a few stills (e.g. post 64).

I tried to figure out the pitch angle during the "coast". Very roughly, taking 63m length and 5,7m fuselage diameter and from the picture above it seems to be 1 diameter up between back and front - I arrive at a pitch of 5,2 degrees. So nothing with above the power curve at TOGA where I would expect 17 degrees or more in constant alt powered flight path.

I am clearly favouring dual engine problems. That was far less than what is available on a healthy 787. But not the slightest hint why. No fumes no strange sounds.
Flight controls seemed still good until ground, the pilot (R.I.P) clearly kept it away from stalling, but he quickly run out of energy. Really sad.

Any other thoughts, quick and dirty calculations on the pitch angle or angle of attack? And conclusion on available thrust.

Oh I forgot, fuselage not equal cord line of airfoil, there is the angle of incidence. What would it be on a B787? But no more than 3-4 degrees, right?
Would be glad if someone with more data could figure out the pitch and AoA and related thrust for a constant speed (I am sure air speed was kept at the minimum, but kept, had they a bit of power at least they would keep the low altitude. Assuming still full elevator control and no trim issues)

This is a higher quality video posted earlier. That is not two engines at TOGA and sounds incredibly like a RAT. I think most commenting about not hearing a RAT are watching the more widely shared low quality vid with very poor sound.

RAT theory plausible IMHO

Kind of, agreed.

Once already airborne and positively climbing, having 2 engines running and possible TOGA should yield as much as 250% of the required performance (100% - one engine out safe flight path 2,4% gradient).

The RAT (if true) is a massive smoking gun. I'd be happy to learn if anyone with a trained eye sees anything amiss with the ground roll and liftoff. I don't (but not an expert).

And it makes clear why it was filmed, it sounds very different to a normal take off, and most probably, it was a suddendly change of sound from 2 engines TOGA to a RAT.

Your profile says this.
How familiar are you with the Boeing 787 flight deck and its controls?

A link to the report Zoot0 referred to:
https://ad.easa.europa.eu/blob/AIR-2..._AIR-22-09R1_1

Excerpt in the spoiler


{there is more, this is just a taste, see the whole report for details}.

Would any of our 787 qualified pilots care to comment on this as it relates, or doesn't relate, to the aircraft's brief flight shown on the CCTV video?

I tend to agree. I taught ground school for the 744, 748, 777, 320 and 330. I used to tell my students the most critical phase of flight is the 3 minutes after 100 knots. That\x92s when critical TO inhibits occur and ADP\x92s (777) come online etc etc. But the elephant in the room for me is thrust reduction. On the Boeing it can be an altitude or a flap setting where the AT will reduce thrust from derated TO to CLB. For the Bus it\x92s an altitude and the crew are prompted to move the TL\x92s to the CLB detent. If at positive rate (or climb) the PM selected one or two units of flap up instead of gear up would the thrust reduction explain the aircraft\x92s response? This would startle any PF and he wouldn\x92t (muscle memory) manually move the levers back to TOGA while trying to follow the FD Bars to maintain V2 and RWY heading.

If the RAT deployment is indeed confirmed then my theory is out the window\x85.

My understanding is that 787s often take off with a substantial de-rate which is why the take-off runs are quite long. If the flaps had been retracted, would an increase to TOGA have been enough to stop the plane sinking?

What if they tried to select gear up and nothing happened due to some software glitch? I presume the gear will not retract if the WoW switch is closed? What about the TOGA switch will that work \x91on the ground\x92?

But selection of TOGA would result in near instant max thrust. How much extra above what they already had at 37\xb0C OAT I don\x92t know\x85. but if they had derated too much due possible data input error, then TOGA would mitigate with near immediate effect? No?

A4

The aircraft can still climb away with the gear down albeit at a slower rate. The TOGA switch is used on the ground to take off. Take Off Go Around. The autothrottle can be overridden by pushing the thrust levers forward and holding or by disconnecting with switches on the thrust levers.

This is likely some animal, either a dead horse or a red herring, your choice.


The power they selected for takeoff was sufficient to get them airborne. Whatever noise abatement protocol was chosen, the power will not be reduced before 1000ft AAL, so whatever N1/EPR (I do not know what indication the engines on the accident plane used) got them out of the runway was still selected.

If lack of power was an issue, this problem started after V1 and likely after liftoff. One working engine would have sufficed to get them out of the runway after V1 and to a relanding, this is a regulatory requirement. That the weight, temperature, air density, obstacle situation and so on allows for this will have been confirmed during the takeoff data calculation.

These happened on landing. On take off there is absolutely no reason for not going to full TOGA if any reduction in thrust is noticed.

Having experience of many crash sites over a long career, taking off without flaps with the config horn/ warning blaring (or not if u/s) is a possibility Also selecting flaps up, instead of gear up at the positive rate of climb call, is also not unheard of and has happened. Both engines failing/ losing power at rotation/ initial climb out would be extremely rare, but not impossible. With the descent and lack of climb clear, unless a mistake of retracting flaps instead of gear, why wasn't the gear selected up as dragging that around is only going to end one way.
he sound from the well documented video would suggest the engines were running, but were certainly not selected to TOGA/ full power which you might expect when faced with high buildings growing larger in the windshield.
Due to the tail section being relatively intact, the CVR/ DFDR will be downloaded very soon, if not already, so we will all know shortly....

I still don\x92t understand the flap retraction theory

It happens- in every airline in the world, ask any of their training/FDM departments. There are reported incidents of it from almost
Every major airline I can think of. Humans are incredibly fallible, I\x92ve spoken to a captain who did this on the 737 back in the day (now flies Airbus) and on that day he caught himself. He said in the debrief after the flight he could not explain why he did it, absolutely no clue.

The issue I have is why one of the most modern aircraft in the world, a thoroughly 21st century clean sheet design with every protection under the sun would not have the adequate protections or performance to deal with this scenario. Surely the 787 has high AOA and low speed protections- those engines should\x92ve been screaming at TOGA LK (or the Boeing equivalent) and the pitch should have been limited regardless of the weight, density altitude etc

Airlines and manufacturers will always try and blame the pilots but I would be truly shocked to learn a FBW aircraft (Boeing or not) designed this century could get itself into such a catastrophic state so innocently. We KNOW many crashes have been prevented by Airbus FBW protections (a few Wizz examples come to mind

This I believe is an option to retrofit. Can\x92t recall the supplier, Honeywell perhaps, not sure on the 737-MAX and whether it has anything fitted as standard.. Anyway the more cost effective option (for NG operators) is to amend SOPs where appropriate. However the U.K. CAA do apparently intend on creating a working group regarding such events. See also the TUI event at BRS.

https://asn.flightsafety.org/wikibase/388602

https://simpleflying.com/aaib-report...f-runway-10ft/

It\x92s worth noting that the acceleration rate was exceptionally low in the TUI event based on the average for that airport. I refer you to my initial post on this thread, it\x92s a risk that there is no config warning horn (to my knowledge) on the B737-800 that will alert the crew, upon selection of TOGA, that the performance solution entered into the FMC does not agree with the actual config. In the case of flap setting, it will only alert if a non standard take-off flap setting is selected. If in the unlikely event TOGA is not pressed at all then\x85..

Airbus have added something of an FWC to their 321NEO aircraft that will alert crew to this - something I\x92d heard from bus mates but wasn\x92t 100% certain on so thanks to those on here that confirmed.

Sorry for further thread derailment, however felt it might be of interest. 787 rated crew on this thread suggest this would form part of the electronic checklist on the aircraft so in the case of the event at hand a red herring.

Gear possibly not selected up due to startle effect after a major event.

Bird strike unlikely to knock out both engines unless there is a flock of them, you might get a single bird into one engine but the odds of two birds each hitting separate engines are pretty long.

Aircraft often yaw slightly after takeoff, particularly with a crosswind which may be stronger in the air than on the ground.

Air India have had issues with pilot training and standards, reports not too long ago of Indian flight schools selling logbook hours which didn't involve any time in an aircraft.

Numerous reports of cabin maintenance issues with Air India, if they can't fix the seats and IFE possibly they can't fix other things.

These days, high resolution cameras aren't prohibitively expensive and installing a few at airports would be better than mobile phone footage.

Wouldn't an incorrect altitude setting pitch the nose downwards and keep power on for the aircraft to accelerate ?

Boeing philosophy is for the pilot to have ultimate control of the aircraft, Airbus try to protect the aircraft from pilot error. Inadvertent flap retraction on an Airbus will result in the slats remaining out and TOGA, which whilst not a guarantee, has saved a few necks.

Possible issue with the particular type of engines fitted to that aircraft, even worse would be an aircraft issue which would have had the same result regardless of the engine manufacturer.

The B787 has enough OEBs on it to fill up a small binder if printed out, some of which state that the issue is known about and the company is working on it.

Hopefully, given the time that the aircraft has been in service, it won't be a systemic problem suddenly coming to light in the way MCAS did on the B737 MAX relatively soon after EIS.