787 falling out the sky

Hiya, I was departing Heathrow and everything was normal until my aircraft set A/P to 0FT and fell out the sky and wouldn’t go back up again, has anyone else had this?

iPad Air 2020
B787-9
EGLL-SCEL

Hi would you please tell us your altitude, weight and speed?

Hey!

Did you ensure that your altitude was set before takeoff to whatever you wanted to climb to? And did it automatically go to zero after you pressed the ALT button anyway?

It happened about 8000ft at 250KTS and about 200000KG, it was well under the max takeoff limit for sure.

Are you saying you set the altitude to 0 or the VS? Also what was your speed and weight?

I had pre-set it to FL360 and it was climbing fine till 8.9K ish

250KTS, alt set to FL360 and 200000KG, just about max landing weight

what was your N1 percentage?

Gotcha. In your flight plan, was there a waypoint with an altitude selection of 0 feet by any chance?

Around 70-80% N1

Non at all and VNAV wasn’t turned on at all

If you could share a replay file here that would be great :)

You can upload it on www.sharemyinfiniteflight.com and paste the link to the replay here so we can all see how the flight progressed.

I’ll send it now hold on

Wow, that’s highly strange. One moment it’s merrily climbing, the next it goes straight to 0 feet.

This looks like a AP disconnect and then you didn’t recalibrate your controls, not 100% sure.

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No, he didn’t disconnect it. The A/P state is on throughout. The ALT jumped straight from 36,000 to 0. Very strange indeed.

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I didn’t really need to re-calibrate as my device was at a comfy level and I even applied 100% trim

Yeah, then I disconnect to try regain climb and it doesn’t work it’s odd

Interesting do you use IF Assistant?

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