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View Full Version : MCP Oscillations or S turns on approach



CBruce
09-18-2013, 09:00 AM
I know this has been reported as an issue some time ago on the PM forum and there is mention of it on this forum too, has been raised as a ticket with PM a long time ago. Is there a resolution?

The problem I and others experienced (one user posted videos of the issue which was identical to mine) was, when in MCP PM mode (not FS mode which works ok) about 20mi from the airport, the plane will start doing small oscillations or s-turns, back and forth, one way then the other. I have the very latest of all PM updates, I tried with just FD1 on and with FD1 and FD2 on, with both NAVs and with just NAV 1, with both OBS set to the course, with just LOC selected or APP selected, but still the same issue. I also followed the Active Sky Extreme guidelines for sensitive aircraft to the letter (How to prevent S-turn issues with certain aircraft autopilots - Powered by Kayako Resolve Help Desk Software (http://support.hifitechinc.com/Knowledgebase/Article/View/11/0/how-to-prevent-s-turn-issues-with-certain-aircraft-autopilots)), but no difference.

In all other respects my a/c (posky KLM 737-800) works like a dream which is why I am anxious to crack this.

I would prefer to use the PM MCP as it must be more advanced than the FSX one. Also, with the FSX MCP, shortly after takeoff LNAV and HDG select will stop working, just will fly a straight line. All other functiosn work. If I change to PM mode LNAV and HDG select work again. The other thing I have noticed (unsure if this is an issue with the PM MCP) is that on capturing the LOC the plane will often overshoot and then turn back and overshoot the other way, etc necessitating disengaging the AP