Auto pilot activation issues

This morning, I activated AP after take-off with only an altitude set, then when I pressed VS, everything went smoothly with no jerk up and down. Maybe this is a trick. I’ll check in solo.
A320

We’re not talking about the same issue here…

If you have a high VS setting in AP and change ALT, it’s always been doing this. It could be improved but it’s not what we’re trying to repro here.

We’re trying to repro a case where initial VS while at 2000 to 2500fpm will trigger a large jolt.

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Did some solo flight take-off tests and noticed that if ALT set to, say 22000, VS set to 0, AP not activated, there will be no jerk if the trim is perfect or nearly (no purple visible) when activating the AP.

So:

@ + 25% trim, could activate at 170kt with no jerk
@ + 20% trim, could activate at 175kt with no jerk

This is actually quite logical, eventhough 20 1 did not work like this.

Would like to know if someone could reproduce this.

Next beta will have a fix.

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Good, it seems like you can now repro this and it is fixable.

thanks for this

Great, thank you!

Sometimes this happens with B777-200ER… After takeoff and stabilize the rate of climb; when i activate AP through VS mode; the aircraft gains more VS than the selected one by pitching up a little bit…

Hi All,

Many thanks to the team for fixing the pitch up issue in the most recent beta.

However, I found now, by any pitch sensitivity setting, the the nose up is replaced by a gradual sink… if you have similar problem?

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Is the VS actually going down? A gradual sink is normal if you are speeding up.

I had the same problem today.

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The autopilot still seems very jerky (overreacting) on activation and v/s change. Changed V/S at 2,000AGL for reduced thrust procedure from 3,000 to 1,100 and the v/s nearly went into the negative. Happened on the A350.

486 (after the autopilot was allegedly fixed in 478)
iPad Pro 10,5
iPadOS 14.1

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@Maxim I am not able to reproduce it with the latest version (484)

What is your weight? Maybe we can try to sync up settings to reproduce.

I took off and was climbing and pressed the ap button with no issue. I turned ap off and tried pressing the vs with the same behavior. No trim on my 350.

I just uploaded a video with this issue (shows W&B settings there too). The first activation of AP I’d say within margin of error (approx. 300 feet change in V/S), but later on I change my V/S thrice to demonstrate the overreacting effect. The first one is me changing the V/S very slowly (decrease) the second one me changing it somewhat normally but still on the slow side (increase) and the final one is me changing it normally (decrease). Have a look:

I see what you mean. What I do if I want to move from 1200ft/min to 2400ft/min is to add the difference 100ft by 100ft, every second or so.
I agree that AP should do it gradually, but I enjoy doing it myself! 😉