787 A/P troubles.

As @TheFlightQuest said. You climbed straight to FL410 with a full tank of gas. That altitude is normally only reached in the last stages of flight with 4-3 hours before landing.
I’m sure you stalled out because you weren’t watching and racked up some violations.
Case closed

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For the 787 (and indeed the 777), if I’m intending to walk away while it climbs I set the speed to 320. When it crosses FL280 this converts to M0.85, the stated cruising speed of those aircraft (at least on Wikipedia). A height no more than FL350 seems sensible for the early stages - if I know I’m going to be around for a bit then I usually just climb to FL320-FL330 (depending on the direction of flight) and then raise it up another couple of thousand feet before going to bed. Yes, perhaps not the most realistic approach, but have had no trouble with this approach so far on overnight long-hauls.

If you’re doing ultra long-haul flights, it’s also a good idea to take minimal passengers and cargo (or none), as this has an effect on your fuel consumption

Edit: Obviously I should’ve read each reply carefully haha…

You should try and do a step-climb. I’ve flown London - Sydney 2 times now. Always start cruise at max FL320. Then as the aircraft gets lighter climb by 2000ft (every few hours). Only get above FL380 in the last few hours of flight.

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As @TheFlightQuest said, you should stepclimb instead of going straight to FL410 which may have caused you to stall during the flight.

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He was flying without cargo or passengers.
FL410 seems fine to me in that case.

A full load of gas is almost twice the aircraft weight. 410 is still a little too high, especially if he is climbing on a high VS.

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The issue is that at 28,000 feet your speed drops. At 340 knots you need to lower your speed to around 310 knots at 25,000 feet. The violations are the result of you keeping it at 340 knots. I usually set my speed to 312 knots past 10,000 feet and watch until cruising altitude.

This thread is officially going in circles.

  1. You climbed at a constant rate, which you cannot do once you get higher, especially in a 787. There are posts talking about that above.
  2. You stalled.
  3. You crashed.

Solution:

  1. Stepclimb
  2. Monitor your device until cruise, then you can leave it unattended if needed.
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ok Thanks for the advice. I have learnt a valuable lesson today!

I think any thread where this is not what was done should simply have this posted and left at that.

We don’t need “maybe a gust of wind” guessing games. It’s not a mystery.

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