Contradictory VS speeds descending

About 35 mins. before landing, while descending from 350 I experienced a slow down on VS and suddenly the aircraft began ascending rapidly. Instruments showed -2400 VS, 480 kts GS. Couldn’t land after that.

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What aircraft did this happen in and would you mind sending a replay?

Do you have a replay of it?
Were you using AP?
What do you mean “couldnt land after that”

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If you weren’t using AP could it possibly have been a calibration error?

Cannot upload video. Aircraft was 738.

Yes, using AP. I decided to end the flight.

Yes, I was using AP.

Do you know how to?


This will help if you don’t


This does very much sound as if you had selected a certain altitude to descend to and reached it, but speed wasn’t engaged on the autopilot so you lost speed, the nose went up and things happened as described. Could be wrong, but sounds very reasonable to me.

By sharing a replay you would make it easier for us to find the root cause though.

Thanks, it is possible. I have tried to upload the replay, but for some unknown reason, I cannot do it.

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