Very nervous thrust control

[marcom 139]

Hi!If I look at the throttle levers in the VC with autoflight engaged I can see them constantly jumping around when I'm flying a constant IAS in smooth weather conditions (no winds whatsoever, no turbulence either).N1/N2 doesn't fluctuate (the engines can't spool up/down quite as fast luckily). Its not joystick noise either as my thrust lever is set to idle with a rather large null zone and I can control the thrust levers quite smoothly with the autothrottle deactivated.Maybe you could tweak the parameters of the (PID?) controller a little better to make it less twitchy. Its quite annoying and very unrealistic (the real A/T is a very smooth system, sometimes too smooth!)Cheers,Mark

[emvaos 13]

Hi!If I look at the throttle levers in the VC with autoflight engaged I can see them constantly jumping around when I'm flying a constant IAS in smooth weather conditions (no winds whatsoever, no turbulence either).N1/N2 doesn't fluctuate (the engines can't spool up/down quite as fast luckily). Its not joystick noise either as my thrust lever is set to idle with a rather large null zone and I can control the thrust levers quite smoothly with the autothrottle deactivated.Maybe you could tweak the parameters of the (PID?) controller a little better to make it less twitchy. Its quite annoying and very unrealistic (the real A/T is a very smooth system, sometimes too smooth!)Cheers,Mark

Mark,What you see is visual animation and the number of keyframes available, not direct output of PID control. If that was so temperamental then your N1 would be jumping around like crazy (40 to 90 in a flash).Bottom line we could cover the entire thrust lever travel with 200 keyframes. Then your frames in the VC would drop to 5 ! Win some, lose some.Vangelis

[metzgergva 28]

Mark,What you see is visual animation and the number of keyframes available, not direct output of PID control. If that was so temperamental then your N1 would be jumping around like crazy (40 to 90 in a flash).Bottom line we could cover the entire thrust lever travel with 200 keyframes. Then your frames in the VC would drop to 5 ! Win some, lose some.Vangelis

Vangelis, I do understand the frame impact and the need to make less keyframes. Now looking at the underlaying FS internal throttle movement (with AFSD) this is also constantly on the move and does not reflect reality, where a few knots deviation in cruise is not constantly corrected. Especially in turbulent conditions the ATS does not chase such small peaks of deviation in both directions.So if the throttle controler would be a bit less precise in matching the speed while in cruise, that should lead to less corrections and in the end also to less frequent jumps of the throttle lever. May be an are of improvement?Best, Alexander

[marcom 139]

Hi Dev-Team,any chance for further feedback on this? It would be really great if you could address this issue in a future SP! Maybe you could add a filter to make the A/T less responsive?Cheers,Mark

[MatthewS 761]

Yes please add as optional setting in a future SP.

[michal 44]

the real A/T is a very smooth system, sometimes too smooth!)

Are you sure? Never flown an aircraft with A/T but based on many aviation forums and real pilot reports A/T can in fact be quite twitchy, some pilots even remark on them being to eager to chase after smallest deviations. Most likely the real MD-11 pilots/testers did not object to the way it behaves. We should have someone with proper qualifications comment on their behavior.

[marcom 139]

Hey Michael,you got me there! The only MD-11 experience I have is from (Zero Flight Time approved) level D sims. However, on that rig, the A/T will not chase speed that aggressively. It wouldn't bother me if the throttle deviations were small, but with the PMDG MD 11 they seem rather large.My experience is that real heavies are much more speed stable than FS aircraft. Given a standard 3