Posts about: "V2" [Posts: 34 Pages: 2]

Magplug
2025-06-12T12:11:00
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Post: 11899141
Like most Boeings, on the 787 you are prevented from selecting the flaps/slats all the way up in one go by the gate at flap 1. If this was a mis-selection by one of the pilots, they would have been prevented from selecting ALL the high lift devices up in one go by the flap 1 gate. Even if you manage to get the lever to the Flaps Up position then below 225kts you should get Slat-Gap protection which maintains MOST of the lift. I have never tried it personally but that's the operation as advertised by Boeing. Would that provide enough lift to save them...... that is really a matter of debate.

The aircraft may have suffered a power loss of one or both engines possibly by bird strike. I have to say that the B787 is the very easiest aircraft I have ever flown when handling an engine failure above V1. The flight path vector and the flight director in the head up display make finessing an engine failure absolute child's play. Having said that the Boeing 787 performance is calculated right to the limits of legal requirement, so there is no scope for mis-handling. If they failed to select the landing gear up, not due to a flap lever mis-selection, but some another distraction, like an engine failure, then the aircraft would struggle to accelerate to V2 to safely climb away.

The B787 derates are calculated to give an acceptable Vmca in the event of an engine failure. That is to say, if you apply any more power asymmetricly the Vmca criteria of up to 5deg of bank towards the live engine will require more control input resulting in more control drag. Our SOP was - If you need it - Use It! Thankfully I never had to find out.

By way of illustration, on the B747-400, leaving the gear down following an engine failure had the same effect as failing two of the four engines.

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FlightDetent
2025-06-12T19:38:00
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Post: 11899657
Originally Posted by nachtmusak
Question: would the ram air turbine (if truly it was deployed) have been capable of providing hydraulic power at their airspeed & altitude?
Possibly yes. The single-aisle, non-ETOPS and 30 yrs older design I am familiar with has a cutoff speed of 140 kts. V2 for 98% real-life scenarios is higher than that. No reason for the 787 to be any less capable.
aeo
2025-06-13T06:15:00
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Post: 11900048
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.

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aeo
2025-06-13T07:00:00
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Post: 11900081
Originally Posted by Bluffontheriver123
Such a terrible shame, condolences to all. It looks inexplicable from the CCTV.

Seems time for a visual evidence review.

There seems to be a RAT theory based on a hyper zoomed artifact and someone showing a RAT deployed on a different airframe. Not convinced about that, you might get a similar artifact from a belly antenna. The noise? CCTV doesn\x92t have noise and the other pictures I saw were from a car in traffic.

Others are are saying it climbed to 500\x92, not sure about that, the highest I have seen visually is less than 300\x92, QNH vs. QFE I suspect.

Flaps vs. Gear definitely a possibility and the AoA was increasing but only after the descent started.

Double EF (If RAT deployment not a red herring) Fuel contamination? Would have to be deliberate as no other aircraft affected, unlikely. Maintenance or crew error, possible unlikely. Bird strike, no evidence.

MTOW error possible but it seemed to take off fine so no reason for the return to the ground.

What about the bang the survivor heard? I suspect you can treat the evidence of anyone involved in an air crash with a pinch of salt. Order of events are often out of sequence even when talking to trained observers in less stressful situations

MCP mis-setting to 100\x92. Engage AP early, often seen, thrust immediately commands to idle by ATHR, starts to sink, extreme startle and forget gear because it appears like a double EF.

I know where my money is but only time will tell, if they get the Black Boxes in good condition, the factual statement should clear it up quickly.
Your MCP theory sounds feasible but doesn\x92t stand up to Boeing VNAV engagement logic (assuming it\x92s typical Boeing) which would mean at 400\x92 the aircraft would still try to maintain V2. It just might pitch the wrong way. Interestingly, the AT system has caused more accidents on the Boeing than the Bus. Much to everyone\x92s surprise considering the TL\x92s don\x92t move on the Bus..

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Southover
2025-06-13T11:18:00
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Post: 11900373
Plane crash near Ahmedabad

Here is a very unlikely scenario. It may be possible that there was nothing wrong with the aircraft.

We have been told the experience levels of the pilots but not how long they have been flying the 787.

The 787 is very automatic and, in my experience, the easiest aircraft to fly. It does a lot of things for you and reminds you of things that you may have forgotten to do. For that reason, in my opinion it is also the safest aircraft around. However, you have to understand what the automatics are doing in order to manage it correctly.

By putting the departure route into the FMC you set up the lateral navigation and also the vertical navigation including speeds and altitudes. After take-off the FMC will command you initially to fly at up to V2 + 20 until flap retraction ( normally no lower than 1000 feet agl), and then increase the speed with flap retraction until initial climb speed and then final climb speed above FL 100.

If your first altitude restriction on departure is 4000 feet (which will be in the FMC) and VNAV is engaged you will level at 4000 feet. But, if prior to departure, you put 3000 feet in the altitude window (maybe as instructed by ATC) the aircraft will level at 3000 feet.

If I remember correctly LNAV engages at 50 feet and VNAV engages at 400 feet agl. And, I may be mistaken, but I think that the auto-pilot could be engaged at 100 feet agl.

Now, I am probably wrong about this, but if you forget to set the altitude window to the first altitude in departure and leave it at 0 (which with some airlines the previous crew will do on shutdown) the following might possibly occur. At 50 feet LNAV engages, at 100 feet the autopilot engages, at 400 feet VNAV engages but as the altitude window is set to 0 the aircraft (on autopilot) now descends to capture 0 feet. The speed at this point in VNAV is low (max V2 + 20 kts) so, to maintain that, both thrust levers close. This, of course, would be totally unexpected and could have a startle effect. If you do not realise what has caused this you might think that there is a problem with the engines and you have very little time to deal with it. I would suggest that putting out a Mayday call at this stage is not a good use of time.

As I stated at the beginning this is probably very unlikely and may not be possible, but could be tried in a simulator.

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Someone Somewhere
2025-06-13T11:34:00
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Post: 11900389
Originally Posted by USERNAME_
IFE being broken on Air India is not groundbreaking news, in fact I\x92ve positioned on more AI flights with broken IFE than I have functioning IFE.
Especially when the video is clearly taken on the ground, when you could easily expect source switching due to shutting down an engine for single-engine taxi, then switch to APU, then ground power.

Originally Posted by Semreh
It's fine that the \x93Enhanced Airborne Flight Recorders\x94 have 10 minutes battery backup. If the bits of equipment/sensors sending data to be recorded don't have power, you will be recording 10 minutes of silence/blank data.

The concept of powering 'critical (sensor) equipment' has been floated - the problem being that it must be possible to power down malfunctioning equipment in case of fire - real or suspected. Having independent power supplies and battery back-ups all around the airframe, each with an ability to lose their magic smoke, is a poor idea.

Commercial passenger jet aircraft already have robust power supplies with multiple generators and emergency battery support. However, if one malfunctions, rather than fails completely, it can be difficult to decide which one to disable, as it can cause problems in all systems.
IIRC the CVR battery (in this case EAFR battery) is required to power at least the cockpit area microphone, if not the pilots' mics.

Once the RAT deployed at least some data should have come back.

Originally Posted by Southover
Now, I am probably wrong about this, but if you forget to set the altitude window to the first altitude in departure and leave it at 0 (which with some airlines the previous crew will do on shutdown) the following might possibly occur. At 50 feet LNAV engages, at 100 feet the autopilot engages, at 400 feet VNAV engages but as the altitude window is set to 0 the aircraft (on autopilot) now descends to capture 0 feet. The speed at this point in VNAV is low (max V2 + 20 kts) so, to maintain that, both thrust levers close. This, of course, would be totally unexpected and could have a startle effect. If you do not realise what has caused this you might think that there is a problem with the engines and you have very little time to deal with it. I would suggest that putting out a Mayday call at this stage is not a good use of time.

As I stated at the beginning this is probably very unlikely and may not be possible, but could be tried in a simulator.
This has been discussed upthread and has happened before (on a 777 IIRC) but did not result in a crash.

It does not explain the RAT and generally you would expect crews to shove the thrust levers fully forward.

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JG1
2025-06-13T12:22:00
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Post: 11900444
Originally Posted by Southover
Here is a very unlikely scenario. It may be possible that there was nothing wrong with the aircraft.

We have been told the experience levels of the pilots but not how long they have been flying the 787.

The 787 is very automatic and, in my experience, the easiest aircraft to fly. It does a lot of things for you and reminds you of things that you may have forgotten to do. For that reason, in my opinion it is also the safest aircraft around. However, you have to understand what the automatics are doing in order to manage it correctly.

By putting the departure route into the FMC you set up the lateral navigation and also the vertical navigation including speeds and altitudes. After take-off the FMC will command you initially to fly at up to V2 + 20 until flap retraction ( normally no lower than 1000 feet agl), and then increase the speed with flap retraction until initial climb speed and then final climb speed above FL 100.

If your first altitude restriction on departure is 4000 feet (which will be in the FMC) and VNAV is engaged you will level at 4000 feet. But, if prior to departure, you put 3000 feet in the altitude window (maybe as instructed by ATC) the aircraft will level at 3000 feet.

If I remember correctly LNAV engages at 50 feet and VNAV engages at 400 feet agl. And, I may be mistaken, but I think that the auto-pilot could be engaged at 100 feet agl.

Now, I am probably wrong about this, but if you forget to set the altitude window to the first altitude in departure and leave it at 0 (which with some airlines the previous crew will do on shutdown) the following might possibly occur. At 50 feet LNAV engages, at 100 feet the autopilot engages, at 400 feet VNAV engages but as the altitude window is set to 0 the aircraft (on autopilot) now descends to capture 0 feet. The speed at this point in VNAV is low (max V2 + 20 kts) so, to maintain that, both thrust levers close. This, of course, would be totally unexpected and could have a startle effect. If you do not realise what has caused this you might think that there is a problem with the engines and you have very little time to deal with it. I would suggest that putting out a Mayday call at this stage is not a good use of time.

As I stated at the beginning this is probably very unlikely and may not be possible, but could be tried in a simulator.
Totally agreed. But at some point with the buildings coming into 8k definition, one would hope that a pilot experienced enough to be employed on a 787 would disconnect everything, firewall it and pull up the nose..

Last edited by JG1; 13th Jun 2025 at 13:15 .
nrunning24
2025-06-13T14:21:00
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Post: 11900563
Former Boeing Engineer, actually worked on this specific airplane prior to delivery. To me this all comes down to if the RAT was actually out. If not, lots of different factors people have already debated and likely some sort of pilot error that I'll let the pilots on this forum debate.

If the RAT did come out, then we are looking at simultaneous dual engine failure basically at V2 which is so improbable (without bird strikes or purposeful actions) that it is basically impossible. This is a 330 Min ETOPS aircraft. I saw no rudder deflection or yaw indicating 1 engine failed first and then they shut down the second one on accident.

Only two realistic options for me in that case are:
1. cutoff of the engines by the pilots. Either on purpose or accidental.
2. maintenance actions by the Air India ground team that caused issues with the engine system or power generation system.

2 is the only one I haven't seen mentioned here and I say this as a no longer Boeing employee. We STRUGGLED with AI during the EIS. They were notorious for just parking airplanes and then using them as spare parts and then screaming for help when they had to go back and get the planes ready to fly again.

Still think 1 is much more likely but will just throw out that 2 since there were complaints from previous flights about IFE and AC which to me speaks to issues with the power generation possibly being neglected.

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Buster15
2025-06-13T15:24:00
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Post: 11900624
Originally Posted by nrunning24
Former Boeing Engineer, actually worked on this specific airplane prior to delivery. To me this all comes down to if the RAT was actually out. If not, lots of different factors people have already debated and likely some sort of pilot error that I'll let the pilots on this forum debate.

If the RAT did come out, then we are looking at simultaneous dual engine failure basically at V2 which is so improbable (without bird strikes or purposeful actions) that it is basically impossible. This is a 330 Min ETOPS aircraft. I saw no rudder deflection or yaw indicating 1 engine failed first and then they shut down the second one on accident.

Only two realistic options for me in that case are:
1. cutoff of the engines by the pilots. Either on purpose or accidental.
2. maintenance actions by the Air India ground team that caused issues with the engine system or power generation system.

2 is the only one I haven't seen mentioned here and I say this as a no longer Boeing employee. We STRUGGLED with AI during the EIS. They were notorious for just parking airplanes and then using them as spare parts and then screaming for help when they had to go back and get the planes ready to fly again.

Still think 1 is much more likely but will just throw out that 2 since there were complaints from previous flights about IFE and AC which to me speaks to issues with the power generation possibly being neglected.
Not yet seen a response to my question about which engine parameters are recommended by the FDR and what is the sample rate.
Hopefully you might be able to answer this.
Many thanks.
I am a retired gas turbine engineer who worked on safety systems and assessments and assisted on a number of accident investigations (military fast jets) and would be interested to know this.

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CurlyB
2025-06-13T19:07:00
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Post: 11900817
Is the V2 logic based off of RA or baro on take off? Just want to rule out a theory in my head that an incorrect pressure setting may cause an incorrect VNAV intervention.

Worse case scenario imo is that there's a latent failure mode, like the 737 rudder actuator
Flaperon777
2025-06-13T21:51:00
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Post: 11900945
Most Plausible \x85

In my opinion ( and we all know the cliche about opinions ), there are only two plausible explanations.
1. Dual engine failure/damage due to multiple bird strikes somewhere immediately after V2 and liftoff.
Given the suddenness of the situation the gear could well have been overlooked by the PM who would be checking out the engine parameters only at this point in time. Flaps were in 5 position. No doubt about that.
Take off thrust used was for Optimum thrust
( meaning minimum thrust for take off given runway and environmental conditions ). That accounts for the full runway length being used. This is policy. That means minimum thrust used for take off to meet 2nd segment climb gradient at almost MTOW.
Loss of total thrust, RAT may or may not have deployed. At 650, AMSL no chance of any relight or turn back. Rest is history.
This also corresponds to the thud heard by the survivor about 30 seconds after takeoff.

2. Loss of thrust in only one engine and degraded performance in the other. Again, due to bird strike. Thereby not allowing even level flight.
Gear staying down could have been overlooked by mistake OR left down intentionally forseeing an impending ground contact by PIC and trying to minimize damage to his airplane.
Eitherways it added to additional drag and if anything, only accelerated the process of ground contact.
Given the above conditions safe flight would have been close to impossible. If not completely impossible. He neither had the airspeed not the altitude to make a 180 or even look for a safer place to put her down.
Refer the last Concorde flight/crash.

A very very sad day for aviation indeed \x85 🙏

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The Ancient Geek
2025-06-14T00:12:00
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Post: 11901017
Is it possilble that both engines were running from the centre tank which actually contained only a little fuel which ran out around V2 ?.
I know very little about the 787 so maybe complete tosh ????
FullWings
2025-06-14T08:09:00
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Post: 11901235
Originally Posted by Greenlights
hello guys,
I'm pilot but not on a heavy one, so I may have a naive question but eh..;depends on planes right ?

-let's imagine, the PM raise the flaps instead of gear (on 787). Is it really a big issue that could lead to a lose of 200/300 feet ?
I mean, you still have take of power ar at least climb power right ? sure you decrease the lift by raising the flaps (at constant speed though ) and lose some height, but the plane keep accelerating ,?
The answer is: it depends. Modern aircraft and the performance software used to generate thrust settings and v-speeds have a complex interplay between regulatory requirements, engine wear, runway length, obstacles, Company policy, etc. Without knowing the entirety of what the calculations were based on it would be hard to say for sure. Also, remember the performance is predicated on losing half the thrust at V1 and continuing the takeoff: if you have had both engines running for a while after that and you retract the flaps early, you are already well above the net single-engined minima, both in terms of speed and altitude, so some fat in the system. Also, if the V2 has been increased artificially, you may have adequate manoeuvre margin after retraction and be far enough along the drag curve for it not to be too problematic. All that said, it is definitely a bad idea to do this off-schedule!
KSINGH
2025-06-14T08:43:00
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Post: 11901266



I’m not a 787 driver so for fear of looking dumb in front of those that are this still confuses me. Even IF they’ve mis-selected the flap setting (I still don’t think it’s been cemented on here that there is in fact a FMS/flap setting disagreement warning but i believe there is), had the wrong de-rated take off settings, selected flaps instead of gear up the 787 with massive high bypass engines, FBW and full envelope protections surely cannot let itself be put in such a low energy/high alpha regime as we saw in the videos IF it has both fans functioning normally, surely?

the pilots may have messed up royally and numerous times so those holes lined up but the plane is the final block in the chain and a 21st century all digital entirely clean sheet design was sold as being immune to such catastrophic outcomes from a few minor (consequential yes) and fairly common errors- aren’t all the protections and our procedures designed after decades of mistakes?

im having a hard time squaring how a fully functioning modern bird like this could allow for this outcome and almost whatever the pilots did outside of unbelievable inputs and the pilots are are a bit of a red herring IMO


Dale Winsley
@Winsleydale
No. The LE slats are deployed therefore the flaps are as well. This is an automatic linkage. The flaps are set at Take-Off. Hard to see from the angle but they are...if slats are out (easy to see) then flaps are set. Looks like Flaps 5. Also, the 787 has the highest Thrust-to-Weight ratio of any airliner on Earth. The change in Alpha and lift is a trifling matter for it, at these settings (1-5). It will fly out of it easily, even at that density altitude. The attitude change is - in the circumstances I describe, consistent with a massive power loss (both sides). I believe based on probability that simultaneous mechanical failure is not the cause. Fuel contamination or starvation is likewise unlikely based on the 787 fuel system. The common element is the FADEC/Autothrottle/TOGO. However, each engine FADEC is dual redundant two channels. So any such common failure must happen further upstream. From a design perspective, that would be unthinkable. But this is Boeing. Given what I can see with my own eyes, I believe the flap issue is a non-starter. Also, re the landing gear: Clearly the Positive Rate challenge would be met based on normal rotation and fly-off at V2. But since we know the flaps were set correctly, that rules out an "oopsie" moment. Just as likely there was at the challenge moment an indication that something was amiss, and the Gear Up call was not made. They see both N1s unwinding and it takes a second to get past the WFT factor. They cross-check and see the airspeed also unwinding. Then they unload the Alpha and pitch to gear down Vy. And they had another 6 seconds. Whatever it was, it was not a flap, mechanical or fuel issue. We will know soon enough. But this is Boeing. My gut says "software". All 787s worldwide need to be grounded, now.
6:10 AM \xb7 Jun 14, 2025
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Last edited by Senior Pilot; 14th Jun 2025 at 09:04 . Reason: Add X quote
Tu.114
2025-06-15T09:46:00
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Post: 11902300
Something rather relevant has not yet been shown on this thread: a performance calculation.

Could somebody with access to a 787 performance calculator please show realistic figures for this type out of Ahmedabads runway 23?

Weather at the time of the accident:

VAAH 120830Z 24003KT 6000 NSC 37/17 Q1000 NOSIG=
VAAH 120800Z 25007KT 6000 NSC 37/16 Q1001 NOSIG=

With 240 souls on board, a payload of 20-22 tons might be a ballpark figure, and a fuel load of about 50 tons was claimed as realistic in earlier posts.

An appropriate flap setting, a flex temperature, V1, Vr, V2, flap retraction and green dot speed (or its Boeing equivalent), a climb gradient after departure, and some distances might be of interest, I\xb4d think.

Last edited by Tu.114; 15th Jun 2025 at 10:50 .

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EDML
2025-06-15T22:23:00
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Post: 11902905
Originally Posted by The Ancient Geek
+
My personal theory FWIW is that the tank pumps never ran due to some fault and the aircraft made it to V2 on fuel in the system (possibly involving the centre tank).
1. The engines will run fine without the tank pumps - at least until FL200. That has been discussed in detail already.
2. The tank pumps are redundant. There are 2 (one per engine) in the center tank and one in each wing tank. Due to the pressure the fuel in the center tank will be used first.
3. There was more than 15t of fuel in the center tank
4. Any fuel in the system would be used up during taxi

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KSINGH
2025-06-14T08:43:00
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Post: 11903718



I’m not a 787 driver so for fear of looking dumb in front of those that are this still confuses me. Even IF they’ve mis-selected the flap setting (I still don’t think it’s been cemented on here that there is in fact a FMS/flap setting disagreement warning but i believe there is), had the wrong de-rated take off settings, selected flaps instead of gear up the 787 with massive high bypass engines, FBW and full envelope protections surely cannot let itself be put in such a low energy/high alpha regime as we saw in the videos IF it has both fans functioning normally, surely?

the pilots may have messed up royally and numerous times so those holes lined up but the plane is the final block in the chain and a 21st century all digital entirely clean sheet design was sold as being immune to such catastrophic outcomes from a few minor (consequential yes) and fairly common errors- aren’t all the protections and our procedures designed after decades of mistakes?

im having a hard time squaring how a fully functioning modern bird like this could allow for this outcome and almost whatever the pilots did outside of unbelievable inputs and the pilots are are a bit of a red herring IMO


Dale Winsley
@Winsleydale
No. The LE slats are deployed therefore the flaps are as well. This is an automatic linkage. The flaps are set at Take-Off. Hard to see from the angle but they are...if slats are out (easy to see) then flaps are set. Looks like Flaps 5. Also, the 787 has the highest Thrust-to-Weight ratio of any airliner on Earth. The change in Alpha and lift is a trifling matter for it, at these settings (1-5). It will fly out of it easily, even at that density altitude. The attitude change is - in the circumstances I describe, consistent with a massive power loss (both sides). I believe based on probability that simultaneous mechanical failure is not the cause. Fuel contamination or starvation is likewise unlikely based on the 787 fuel system. The common element is the FADEC/Autothrottle/TOGO. However, each engine FADEC is dual redundant two channels. So any such common failure must happen further upstream. From a design perspective, that would be unthinkable. But this is Boeing. Given what I can see with my own eyes, I believe the flap issue is a non-starter. Also, re the landing gear: Clearly the Positive Rate challenge would be met based on normal rotation and fly-off at V2. But since we know the flaps were set correctly, that rules out an "oopsie" moment. Just as likely there was at the challenge moment an indication that something was amiss, and the Gear Up call was not made. They see both N1s unwinding and it takes a second to get past the WFT factor. They cross-check and see the airspeed also unwinding. Then they unload the Alpha and pitch to gear down Vy. And they had another 6 seconds. Whatever it was, it was not a flap, mechanical or fuel issue. We will know soon enough. But this is Boeing. My gut says "software". All 787s worldwide need to be grounded, now.
6:10 AM \xb7 Jun 14, 2025
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fdr
2025-06-17T10:12:00
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Post: 11904166
Originally Posted by Turkey Brain
.
....

Rotate vs. Air/Ground Switching Vs Pilot action

(This is my take, it might seem counterintuitive, if you know better help) On a normal takeoff at rotation, liquids don't slide backward any more than they do during the takeoff roll itself. They slide back during the takeoff roll, and at rotation, there's actually a slight reduction in those backward forces. The main force is still pushing them back, but because the wings are now generating lift, there's more drag than when the plane was just rolling on its wheels. So, if liquids have pooled at the back of something at rotation, during and just after that maneuver, they'll actually ease forward a bit. The main force is still pushing them back, but it's less so. My take is if something sudden happens around rotation, I think it's probably more connected to something like the air/ground sensing or pilot action, but it is still possible that pooled liquids sloshing forward a little could also cause it.
Pilots have to do a few things at rotate time, pull back in the controls, not the thrust levers in error and then move the landing gear lever. Over the years there's been a few action slips, so unintended control movements.
Pooled water around the moisture barrier is just looking for a suitable access point to drain into. The 3 events I am aware of in the B744 were all during manoeuvring, 2 at rotate and one during a descending turn.
Spoiler
 


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Capn Bloggs
2025-06-17T14:17:00
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Post: 11904336

Originally Posted by Squawk7700
Perhaps?

Originally Posted by Squawk7700
  • Takeoff proceeded normally, TOGA used.
  • Autothrottle entered HOLD mode at 80 knots .
  • VNAV or FLCH was NOT engaged after liftoff.
  • Pilot assumed A/T was managing thrust, but it wasn’t.
  • Pilot focused on pitch/flying manually.
  • Thrust stayed fixed or decayed (if levers were moved).
  • Speed decayed, aircraft climbed too steeply, energy bled off.
  • Pilot assumed engine failure due to poor climb response.
Boeing SOPs typically include a callout at 400 ft like:

"LNAV" - "VNAV" or "FLCH SPD"

To ensure:
  • Proper navigation mode is active
  • Autothrottle resumes thrust management
  • Aircraft transitions smoothly into the climb phase
Some questions, if I may:
VNAV or FLCH was NOT engaged after liftoff.
When is the crew expected to do this? Wouldn't it be armed prior to commencing the takeoff so that it (one or the other) would engage automatically?

Pilot assumed A/T was managing thrust, but it wasn’t.
How does the 787 "manage thrust" after takeoff? The jet has only just left the ground; surely the throttles would be at maximum power and pitch would be used to attain and maintain V2 until the end of the second segment.

Pilot assumed A/T was managing thrust, but it wasn’t.
Are you saying the pilot( s ) just sat there while the ATS reduced the thrust (because is all it could have done, as it was at maximum for the actual takeoff).

Thrust stayed fixed or decayed (if levers were moved).
Fixed on what? Or did it "decay" because the PF pulled the throttles back?

​​​​​​​Speed decayed, aircraft climbed too steeply, energy bled off.
There is no evidence the jet climbed too steeply; I assume you saw the granular FR24 plot (from FR24 itself) which showed the initial flight path of this one was in the middle of the range, and the video clearly shows a normal initial climb and deck angle before "the @#$% dropped out of it".

​​​​​​​Pilot assumed engine failure due to poor climb response.
So BOTH pilots just sat there, didn't pull the gear up, did nothing else and crashed it (pretty well, I might add, with superb pitch control right to the last second).

Boeing SOPs typically include a callout at 400 ft like:
"LNAV" - "VNAV" or "FLCH SPD"
To ensure:
  • Proper navigation mode is active
  • Autothrottle resumes thrust management
  • Aircraft transitions smoothly into the climb phase
Interesting but totally irrelevant as the jet never got above 200ft.

You're clearly implying a complete ballsup by the crew, making multiple serious mistakes or errors of omission.

Last edited by T28B; 17th Jun 2025 at 15:40 . Reason: formatting clean up

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Capn Bloggs
2025-06-18T00:52:00
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Post: 11904808
Originally Posted by KSingh
what is the DGCA’s extra inspections of Indian 787-8s about? Just to reassure the flying public?
I wouldn't be surprised.

Originally Posted by Chieftp
​​​​​​​ 767 pilot here, on the 767 it would capture the altitude, but more importantly, it would freeze the airspeed at whatever speed the alt capture occurred at. So the thrust levers would retard to maintain the much slower speed at the point of capture. This could be a possible scenario, especially if the crew was slow to realize what happened, AND the 787 has a similar low altitude capture issue.
The speed should be at least at V2 and probably higher. Why would the ATS not just hold that speed, albeit being a shock to the crew. Within a few seconds I'll bet the throttles would end up back in the forward position as the ATS says "hey, we're slowing down fast here!". It would be ugly but I can't see that the jet's going to drop out of the sky. The throttles aren't going to come right back and stay right back.