This site is being deprecated.

Please see the official X‑Plane Support page for help.

0 votes
asked by (20 points)
I am experiencing a problem that seems like a glitch but could easily be 'pilot error'.  Let's suppose I'm in Peter Hager's (beautifully modelled and deliciously complex) A380, at SPEED, CRZ ALT, and NAV, tracking the flight plan perfectly.  Now, for whatever reason (following a tutorial prompt in fact) I 'pull' the heading knob (clicking right on it), to enter HDG mode, the change registering in the FMA.  I  immediately (about 1 second later) push the knob back in by clicking just above it.  The FMA still registers HDG, and the aircraft 'refuses' to go back to NAV mode, leaving me to effect all lateral nav manually.  What am I doing wrong?  Why won't the aircraft reenter NAV mode?  Peter has patiently explained that while HDG is always available, not so NAV, and that if the aircraft's course is divergent, NAV won't arm, or activate.  That makes perfect sense, but how can course be divergent after only a second or so, and no course parameter has been changed other than switching from NAV to HDG?  I would be very grateful for any enlightenment.  I hate to pester Peter any further - he has been very kind and prompt.  I'm a newbie at chiming in on the forum.  Please let me know if I'm out in some way in protocol.  


1 Answer

0 votes
answered by (332 points)
selected by
Best answer

while this is a X-Plane Q&A and not a support forum for other 3rd party software, I will still try to help you. I am a rated A320 Captain, and I suppose that the A380 FMGC works in a similiar way.

What you described should work. If close to the green path, NAV should re-engage. If you are far away from the green line AND the track is actually divergent, you should get a message in the scratchpad that tells you so.

It could also be that you are not correctly "pushing in" the heading knob, thereby never going back to NAV mode.

To work around that problem, why donĀ“t you use the DIRECT TO button and simply fly direct to the current to-waypoint?

Good luck, Jan
commented by (20 points)
Jan - thank you so much for your kind help. Your suggestion regarding the 'direct to' button absolutely solved the problem.  When I hit that, NAV reengaged.  I had tried the 'direct to' recently in a maneuver outlined in the tutorial and it didn't work, but I think it was because I hadn't scrolled to the correct waypoint in the 'direct to' page.  I repeated the test a few times, sometimes NAV reengages directly - others it arms first, then engages shortly thereafter.  In any case, I'm thrilled to have that problem solved.  Thanks again!