Bobbing at cruise


#1

Hey everyone. This is going to be a short rant so read if you want. I have previously made a topic about the 777-300ER bobbing at cruise. I don’t know if any of you haven experienced this in this aircraft but it makes it unflyable for me which is really disappointing. Anyways a couple days ago the bobbing started happening in every aircraft I fly. I have heard of this happening to others as well. I always am trimmed correctly and I am never climbing too aggressively or anything (max of 1500fpm before leveling off). I have tried turning off altitude hold and setting vs to 0. This sort of works but I sill bob a little and slowly descend or climb over time. I just hope the devs know about this issue and try to fix it in future updates. I appreciate all of their hard work and thank you for reading this. If you made is this far have a donut 🍩!


#2

If you bobbing just a little bit (a few ft higher or lower), you are fine. The cause could be strong winds in your area.

What really is a cause for concern is if you are bobbing up and down violently. Then that could be because of your weight and that you need to descend to accomodate that weight.


#3

This is an issue in some aircraft yes, but on every aircraft is not seen at all normally. Could you list some of the aircraft you have flown that have had this issue along with the weights, altitudes and speeds you have been flying?


#4

I know what you mean. However what I am describing is an over correction. Not just bumps from turbulence.


#5

Last night the A380 at 77% load at FL310, M .85

Currently the A320 at 44% load at FL350, M .78

These are two planes that I have never had this issue with before.

*The A380 was an overnighter so I did stepclimb but I do not know if the plane was bobbing for the entire flight because I woke up directly over my destination airport 😂


#6

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.


#7

I have the same issue. Really annoying


#8

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.


#9

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.


#10

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.


#11

Please read :)


#12

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.


#13

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…


#14

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


#15

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!


#16

Will do. Might be a day or two though!


#17

Any updates?


#18

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.


#19

Yes please, never seen this myself.


#20

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.