What am I doing wrong that might cause the RPM to spike repeatedly every 3 seconds? I'm fairly certain it happens only on descent and/or approach, which leads me to believe maybe I'm not managing cabin pressure correctly. But why would that affect prop RPM?Crude diagram of RPM issue:^^^^^^^^_________________^^^^^^^^__________________^^^^^^^^__________________^^^^^^^^__________________^^^^^^^^_________________ Ctrl + C

Edited February 23, 201214 yr by bud7h7

Cabin pressure wouldn't effect RPM. It sounds like a hardware issue (spiking hardware levers) or extreme wind gusts (they're all over the east coast US tonight if you're using real weather).

My first thought was wind gusts but the spike intervals are perfectly consistant. There are no other controllers connected, just the one yoke, so no conflicts there.

When u get the rpm spikes look at the IAS and see what it is doing. I had the same problem. It was a weather related issue.

Yes that's right, I failed to mention that the ASI spikes in sync with the rpm, and how large the spikes are depends on my speed. If I slow down they are less pronounced. Seems odd that this happens to me nearly every flight.

Yes that's right, I failed to mention that the ASI spikes in sync with the rpm, and how large the spikes are depends on my speed. If I slow down they are less pronounced. Seems odd that this happens to me nearly every flight.

What weather program are you using? We need info here!

Edited February 23, 201214 yr by ZachLW

You could not possibly be talking about the engines' resonance oscillating when they are out of sync are you? That is about every 3 seconds or so.Kind regards,

You could not possibly be talking about the engines' resonance oscillating when they are out of sync are you? That is about every 3 seconds or so.Kind regards,

If turbulence is enabled, one can suffer from some strange RPM spikes. Disabling turbulence, setting the scalar to .05000, or using DWC (Active Sky) with the latest FSUIPC can solve the issue.

Edited February 23, 201214 yr by ZachLW

I will make my next flight with no weather for troubleshooting. If it happens again I'll make a video.I'm using AS6 weather engine, and in FSUIPC I have wind gusts near aircraft suppressed but not eliminated. Like I said earlier though, the spikes are in perfectly regular intervals. I would think wind events would have a more random effect.

update:it is definately wind related. Today I noticed that when the rpm spikes, the ASI spikes with it, and I can visually see the aircraft reacting to the wind gusts. Time now to move my focus away from the aircraft to my weather program (AS6.5) and also FSUIPC. I assume there aren't many people still using AS6 with FSX? Maybe that's why there are no other posts with similar issues to mine.

check your setting in as6, should beFSUIPCWindSmoothing = True

I think I saw similar effects with ASE at my GA planes. So the age of the actual weather program in use may not be the cause, but the philosophy may be. However, the registered FSUIPC is magic and those settings helped.Note the Suppress these wind effects settings.