Manually landing

Good day!

When I land I have quite a problem. For example, if I want to land manually and turn off the autopilot, I always have the problem that every time my nose either goes very down or up and I stall or overspeed. Does anyone know how I can avoid this?

Btw, i only fly the 777-300.

Have you tried calibrating? Otherwise speed might be a problom.

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No, it is just how much degrees i need to hold my ipad.

Ahhh then that’s the problem, if you hold your device steady in a comfortable position and calibrate you should be good. There is no set “degrees” you need to hold at. Calibrating solves the problem.

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What calibrating does is it sets the “no altitude change” degree to whatever you want. If you hold it in that position, the plane shouldn’t go up or down.

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Remember to trim out your aircraft before deactivating autopilot. Even if you calibrate to your comfort, it won’t account for the extra input you’re no longer adding that the autopilot is doing for you. Make sure you trim out your aircraft so that no input would be needed to maintain your course (indicated by the lack of a pink line in your trim tab).

Preventing this also comes down to how you’re approaching the runway. Your autopilot trying to pitch up or down (again indicated by the pink trim line) would mean it is trying to deviate from where the aircraft would naturally want to fly; for example if it is too fast, it will naturally balloon upwards, and vice versa.

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You could try turning off the different autopilot systems one by one instead of turning them all off at the same time by pressing the A/P button

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that is not the problem, i will never do that, lol

As @Tsumia said, trim the plane first as since your disabling autopilot, it’s no longer accounting for you pitching up and you have to manually do that now.

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I definitely calibrate at various critical times (extra precaution if nothing else) but I don’t believe it sets a “no altitude change” change position.

I tested this just now with the OP’s aircraft. From being on AP, and after a speed or other change, I calibrated and then without moving control angle, turned off AP. It still consistently changes pitch.

So calibration doesn’t appear to set neutral trim. I think it sets the position of the control’s response range. But one has to manage neutralizing trim separately.

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Then, that’s something to do with AP.


Here is my little experiment, where I put my iPad on a table after calibrating in a different position.

I, then, calibrated, and see how pitch was neutralised to 0%.

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I’m in the process of reproducing what you did, but is pitch 0% the middle of the pitch control range, though the trim neutral position changes from that pitch 0% position depending on speed and configuration?

So your pitch is now 0 with calibration, but trim neutral is not necessarily at that point(?).

To the OP: this is almost a case where it’s helpful to see a video example. This is because it could be related to several different factors such as speed, flaps, when AP is turned off, as well as calibration.

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I’m quite confused, so please enlighten me. How would trim not be neutral when pitch is, with no external factors affecting it? @adit

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I think neutral pitch is when the elevator on the tail is neither deflected up nor down. Typically, in flight the elevator is constantly deflected at some angle to keep the plane from changing pitch (due to balancing out other changing pitch forces that change with speed, flaps etc.).

So neutral trim is when the elevator is set to stay in the appropriate deflected position (to prevent pitch motion), with no effort necessary on your aircraft control input column (stick, device etc) to keep the elevator in that deflected position.

So the neutral trim is the no input force setting to keep the elevator in whatever position it needs to be (which in general will not be the pitch 0% position).

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I see. I did some testing and it looks like you are correct.

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So the trim tab on the elevator is like the elevator’s elevator. You set its position to do the heavy lifting in holding the elevator’s deflected position.

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In order to have a smooth autopilot transition, whether you’re engaging autopilot after takeoff or disconnecting for approach, make sure that you set the trim so that you can no longer see the purple line, meaning the yoke is at neutral, then calibrate. That way, neither you nor the autopilot will have to take over and try to find the correct yoke position.

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I believe that’s true and good advice to the OP to offer the best chance at resolution without more info.

(But, separately, I’ve assumed there are two different neutrals: yoke neutral and trim neutral. Yoke neutral comes from calibrating; trim neutral from removing the purple line. But this brings up…which I won’t bring up)

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