Vertical Speed Overcompensation

Hey guys. Ever since the global update I’ve noticed the autopilot has become a lot “dumber” when it comes to vertical navigration, specifically vertical speed. Before global, I could set my descent rate of, say, -2500fpm and the plane would lower the nose and match it almost perfectly. Now, I’ll set -2500fpm right off the bat and it will descend to anywhere from -3500fpm to -4000fpm depending on the aircraft. Also, when I’m trying to hold an altitude at a low speed (mostly being vectored by ATC in busy airspace) it struggles to hold altitude, descending at like -300fpm to lose 15 feet and ending up in an endless descend/ascend cycle just to make up 15-20 feet. Does anyone know why this happens and if there are any plans to fix/change it soon?

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I’ve noticed this happen a lot, especially with the CRJs. I know they’re sensitive, but it would be nice to see autopilot account for that.

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Oh god even worse is how it fails at turning.

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And don’t get me started on how horribly the speed autopilot works.

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245kts set = 265kts and violation lol

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Just learn to compensate for it…

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Is this with all the aircrafts that you fly, or just certain?

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I have lol it’s just annoying, especially with the altitude hold thing and APPR in bad visibility

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All of them. I adjust the speed slowly so it doesn’t happen but still

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The same thing happens to me. I’ll set it to -2000 and it will go straight to like -2800, then settle to -2000 even when I’m below MLW. It happens no matter what plane I’m in.

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I 100% agree. It is an unfortunate reality, the autopilot is flawed and there is a major problem. I have just delt with it but I may call ghostbusters to rid the demon that makes my plane go from 1800 vs to 5000 on every flight…

Hollywood worthy.

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I have never experienced an “Overcopensation” that bad before. I usually only use 2000fpm right after I lift off, and by the time I reach 5,000ft I have the fpm only around 1500. No issues. Hopefully it never happens to me…

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Are you sure it doesn’t happen to you? Because I believe that it happens to everyone

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I haven’t had this problem, what speed are you usually at when descending. The higher speed may have more of a large reaction.

Tell me the sorcery that you use 👁👁 lol

I think it depends on when you active the auto pilot. I usually press the auto pilot button around 1000ft after lift off. I just make small adjustments only adding or subtracting 100fpm every 10 seconds or so, so the auto pilot doesn’t have to process large inputs (for instance +500fpm.)

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1000 is a good number to activate AP at.

I’m about to start a flight from lax to London on the 777-300ER. I’ll see if I notice anything…

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What trim are you using? (I assume most of your issues are mainly during takeoff and landing) I personally use positive 20-30 trim on takeoff and positive 20-50 trim on decent/landing. (I might be doing trim all wrong but it works for me :)

Btw no issues on the takeoff. Just about to pass through 20,000ft with a stable VS of 1300.