Blackbird Sims / Milviz Forum Archive

Hello,

as a P3D v4.4 user I fly the 737-200 just non RNAV using the VOR/LOC mode of the autopilot.

I have a problem with intercepting the radials of the VORs. No matter of the size of the intercept angle (10, 20 or 30 degrees), the aircraft seems to initiate the turn much too late, and she always misses the radial the first 3-4 attempts. Once the radial is missed, the aircraft turns the other way and misses the radial again, but not that far like the first time. In this way the aircraft performes mulitple turns / curves until it is really aligned with the radial. But in most of cases by then it it's already time to tune in the next VOR-Station.

On the other side, when I hook the airacft up to my Aivlasoft EFB and press the FS-Buttons "NAV/GPS" and "Follow NAV1" (so I could theoretically could fly RNAV tracks), the aircraft is always turning in time and perfetly aligned with the track.

My questions are:

Am I doing something wrong? What is the correct procedure? Is there a possibility to make the autopilot turn the aircraft earlier for proper radial intercept?

Thanks in advance!

Best regards,

Elgee

What you are describing is that the aircraft is making a series of "S" turns during the capture mode, with the period of each each crossing of the radial decreasing, but never quite settling down "on track."

Since the S77 autopilot is scripted to use default FSX/P3D commands, the FDE needs the attention of an FDE specialist, which I sadly am not. It is likely that some adjustments to the PID section of the aircraft.cfg file would mitigate this behavior.