Bobbing at cruise

FINALLY! Someone else experiences this on all aircraft. This is the same exact thing that has happened to me. It used to be only the 77W and A321 that would have the bobbing glitch, but now every single aircraft I fly bobs up and down at cruise.

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I have the same issue. Really annoying

I had it on the 737 the other day. It’s honestly the most annoying thing. It reached the points where the bobbing was so violent I stalled out and… Well let’s just say I oofed.

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Sometimes it happens with the 757 and 767. It bobs and bobs and if I set the vs to -100, it just fixes. But as soon as I set vs 0ft it starts up again.

Someone can make a recording and share it? Might be real life turbulence or something else of course.

@Pilot_B the 320 & 380 numbers and FL you shared should be perfectly normal 👌. With “I am always trimmed correctly” do you change the trim? With the autopilot on I never touch it and never have had this issue myself.

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Please read :)

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I have read this before and I accept the fact that it happens with the 77W and A321. But happening with every aircraft even without altitude mode on and v/s at 0, as well as never exceeding 1000 f/pm right before cruise, is frustrating.

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How fast are you going when this is happening? Only time I’ve seen it happen on other models is when you’re about to break the warp threshold…

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M .78 on an A320 and M .85 on an A380.

Weird. I have never seen it or really heard of it before. If you could record it, upload to YouTube and link… it would be great!

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Will do. Might be a day or two though!

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Any updates?

If videos are needed, I will record my next flight. It happens with me at normal cruise speed/height in all aircraft in IF now.

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Yes please, never seen this myself.

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As a side note, I have seen some reports of the oscillation becoming so violent that the aircraft when stall when pitching up. This has never happened to me, the closest I have come is the 777. I average around -800 to 800 ft/m oscillations on it, which is around a 140ft altitude drop/climb for each cycle. To experiment a while ago, I left it in the oscillation cycle overnight on a long haul and woke up to the plane still flying(but still oscillating), which shows that the oscillation rate stays constant mostly once it reaches a certain level. Not sure if this is any insight but I found it interesting that it got to a certain point and stopped getting worse for me.

The 777/A321 is pretty known, but it is the others we’re new too :)

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Must be going pretty fast or too heavy. That’s the only time I’ve ever experienced it happening.

Sorry guys. Haven’t had much time to fly recently.

@Aernout @schyllberg Here’s the link. B739 FL320 M .78 60% load. I know there is turbulence but you can clearly see the overcorrecting. https://youtu.be/ACGO8pv0aZs

The A321 if you load more cargo in the back and neutralize the trim GENTLY at cruise to show no magenta will steady out-it May bob a LITTLE with heavy wind but it WILL settle with more load in the back I’ve found. Other than that-as Schyllberg said-lock your VS. To do that, I begin reducing VS about 2000’ prior to TOC so that at say FL357 I’m down to 200 VS and I get to 0 VS at 360

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