Slow to capture FMS track?
-
Back to flying this amazing aircraft recently. One of a kind!
I've noted that the flight director / autopilot seems to wander back and forth across the desired track a few times before settling onto course. This can be on initial capture or during a turn at a planned waypoint. The FD wander can make hand-flying a smooth track challenging as well.
Is this true to the real aircraft, or just how the sim works in this case? Any quick config file edits that can tighten up the capture behavior?
Cheers, and thanks for this wonderful machine. -
Out of curiosity, what's the distance to your next waypoint when you see this behavior?
-
I never thought to check that. It happens on a regular flight plan route, so that distance could be 5NM to 150NM. Seems to hunt for center for a while before settling in.
On my flight last night, I did note that the FD/AP was very solid when tracking large changes using the heading bug. So it's related to NAV mode. Is it possible that the CDI sensitivity is too high for enroute navigation? I know some units have different settings for enroute vs approach. -
Several flights later, I can confirm that the hunting for center occurs on just about every turn when on autopilot and tracking the FMS on nav. Turns between 10 and 90 degrees, doesn't seem to matter the distance to the next waypoint. The aircraft performs the primary turn left or right, banks back the other way about 10 deg, then opposite bank 5 deg, before settling on the track after 2-3 oscillations.
I will try this tracking VOR next time to see if it holds true there too. It locks onto a path properly using heading mode and setting the bug.
Is it possible that the Nav mode lateral sensitivities are reversed? I ask because I was flying an ILS approach last night, and the flight director was not providing accurate lateral guidance for deviations. Showed on path in the FD, while the CDI needle on the HSI was slightly offset, and not consistent with wind direction. -
@C-FJDH I believe the way the starship is modelled is accurate. I don't believe the Starship NAV mode uses GPSS and thus will roll hunt to center the CDI similar to tracking a VOR. Best option is to center the CDI using HDG hold and then engage it, or place the aircraft near the correct HDG and then use direct to if practicable.
-
That may be true. I just completed a flight using VORs only, and the FD/AP behaved the same way. Hunting for center.
More of a concern though, was the AP dropping out of NAV mode to ROLL several times throughout the flight, even when close (20nm) from the VOR. And once from APP mode it dropped back into ROLL.
