A320 trim bug

Haven’t seen this bug being reported by other uses on IFC. I’ve experienced this issue for almost 2 years now.

Whilst executing an ILS approach in a A320 with AP disconnected at around (3 DME) the aircraft is trimmed out nicely. Later on durning the approach I disconnect AT and experience a severe pitch down motion which require quite a lot of back pressure. This doesn’t make any sense and can’t be a realistic feature.

Hope the bug can be fixed soon!

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Did you slow down at all in that time period - if you change your speed drastically the aircraft trim may need adjusting.

Also make sure you have enough flaps for your speed - otherwise you will stall.

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No, by 3 DME I was fully configured. So Gear Down, Flaps full, IAS was at a stable 140kt.

Are you sure you calibrated your device before disconnecting the Autopilot?

Yes, I always recalibrate my device before disconnecting the autopilot. But that’s not the issue here, it’s AT which is completely unrelated to trim control…

Could you share the replay.

You can do so via this website:

It happened on the first leg on short final (600ft msl). You might not see a big drop but that’s because I reacted quickly with a big deflection of the elevator.

Looking at the elevator in 3rd person view I can see that it reset to the neutral position during AT disconnect. Also it wasnt a ILS but vis approach, my bad.

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That is indeed odd - took me a minute to spot it because it was a subtle dip.

But if your aircraft was properly trimmed and device calibrated I can’t think what else could cause that.

Let me see if I can recreate it.

Yeah it didn’t happen on the return leg, but I’ve experienced it’s multiple times before. Must be a bug (as I’ve said before) because the AT shouldn’t act like this.

Yeah I wasn’t able to recreate it just now - but I’ll keep an eye out for it happening next time I fly the A320.

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I don’t think this is a bug. When I first started flying on IF, I didn’t add trim and never recalibrated. This lead to a sudden dip of the nose once I turned off the AP, especially if the aircraft is too nose heavy. Once I got a little more experienced, I began trying several trim amounts until the nose didn’t drop, or it did very little. This is all without recalibrating. It varies from aircraft to aircraft, but on the B737 I use 15% trim for landing at Flaps 30° and 135kts. It works wonders.

Try some flights in Solo and find the trim that best suits you.

Please read before typing…

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If by AT you mean autopilot, I’m fairly certain this isn’t a bug. It’s happened to me on numerous occasions and every time I was not trimmed properly. What percentage of positive trim were you using (if you can find it)

AT means AUTO THROTTLE

Auto throttle? I have never had an issue with that before, so I’m very curious now

How often do you experience this issue

Once every 2 or 3 flights, it must be a bug because it resets the elevator to the neutral position

Very interesting… I don’t understand how the throttle could be connected to the elevator though. I guess I’ll have to do some testing of my own later. In this case I’m thinking its probably a bug, but I’ve never experienced it first-hand so idk for sure

I can assure you that that’s not a real feature, hopefully the devs can fix it in the future

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