737 cruise instability

Hello Aviators…
Currently I’m cruising at FL340 with the 737-800… My load is 35% and have 15 knots tailwind… My aircraft is bobbing up and down… Am I doing something wrong or the turbulence would be the cause?

Could it be the VNAV? I noticed you turned it on. Make sure to only turn it on a few minutes before your TOD.

Can you try turning it off?

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Could be turbulence

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I don’t think it’s related because i always arm VNAV in cruise if i fly to an uncontrolled airspace… However i tried to turn it off with no difference…

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From what you’re describing it seems like regular turbulence. If you tell me what server and what region are you over, I can run a quick test myself.

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I guess it’s likely a turbulence that’s causing the shaky experience …irl pilots climb higher or descent to avoid turbulence …
Nothing to worry about once u reach far y shud be fien …

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Maybe you reached cruise while doing an unreasonable v/s?

Absolutely not… My V/S before reaching my cruise altitude was 200ft/min…

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Okay, just a guess, idk what your normal climb v/s is and you were 22min into your flight 🤷‍♂️

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I think yes! Turbulence is the logical cause

Thanks for offering a help 🙏

What is the maximum V/S you’re aircraft is doing while it’s bobbing? You can see it on your HUD below the altitude section

It reached 315 ft/min… But fluctuated between 120 to 280

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That’s not too uncommon. Whenever I’m flying depending on the conditions my aircraft will also do that. I’d say it’s a mix of that combined with the turbulence you are experiencing. So I don’t think you need to worry about it too much

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Thanks a lot for participating… I have the same thoughts so i left everything as it was…
But i wanted to double check cause I haven’t flown B737 since a long time

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No worries :)

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