Jittery, NAV1, Autopilot, CTD issues all together



  • After some very smooth and satisfying flights, I've just had one with various things going wrong together:

    I'm flying on autopilot, heading hold and altitude hold at 2,500ft and that's working fine.

    The wind is 40 degrees off the nose at 4kts but the plane is not flying smoothly at all, sort of continually bouncing around as if in turbulence but I'm flying over level open terrain. I'm guessing this may be the jittery motion some have been describing, which I haven't experienced before in the same flying conditions.

    NAV1 is not working at all no matter what I do, despite being set to exactly the same as NAV2 (checked and double checked), which is working. (EDIT - This has only happened this one time.)

    I switched off the autopilot without switching off heading hold and altitude hold first, then when I engaged autopilot on heading hold with the heading bug set straight ahead it veered violently right. Disconnected the autopilot but still had to fight the plane. I'm guessing not turning off heading hold and altitude hold first may have caused this.

    After a few minutes of fighting the plane it crashed to desktop.

    Thankfully this is not the norm for me and I'm enjoying this plane immensely but it certainly spoils the enjoyment when this happens.


  • JF Staff

    Whilst this is not a support forum, please submit all bugs to the below link

    https://support.justflight.com/support/home



  • @Craig Thanks. Already done.



  • @Sender46 said in Jittery, NAV1, Autopilot, CTD issues all together:

    NAV1 is not working at all no matter what I do, despite being set to exactly the same as NAV2 (checked and double checked), which is working.

    Make sure your CDI is set to VLOC, not GPS. This is a common mistake.
    If you're using the GNS100, there is somewhere a hidden clickspot to change the CDI, but you also can switch to GNS530, set the CDI to VLOC and switch back to GNS100.



  • @copper Thanks for your suggestion.

    NAV1 not working has only happened the once. I haven't been using the GNS430 or GNS530 and with the GNS100 not able to be used as a GPS, the navigation equipment must therefore default to NAV mode rather than GPS. So I don't understand how I could have made a mistake of setting the CDI to GPS, as there is no apparent way that I can see for me to do that with the GNS100 selected.

    If there is a hidden clickspot on the GNS100 to change to GPS mode, would the GNS100 give some indication that it had been clicked on? And even if it was somehow in GPS mode, surely the NAV1 VOR should still pick up the VOR signal it is tuned to?

    It has only happened the once, so maybe I did do something wrong, I just don't know what.



  • @Sender46 said in Jittery, NAV1, Autopilot, CTD issues all together:

    If there is a hidden clickspot on the GNS100 to change to GPS mode, would the GNS100 give some indication that it had been clicked on? And even if it was somehow in GPS mode, surely the NAV1 VOR should still pick up the VOR signal it is tuned to?

    Well the clickspot is somewhere near the magneto switch, I guess you could see the current state on it's tooltip just like with the altitude hold clickspot.

    When setting CDI to GPS, I think the VOR1 gauge also shows the GPS track, not the NAV1 radio signal, but I'm not entirely sure.

    Since I'm not using the GNS100, I'm not sure how you could get into the situation that the CDI is set to GPS. It might be that you earlier used another GNS and have state saving on, but maybe there is some logic behind it (like if you planned a route in the world map) which automatically swichtes to GPS.
    I, too, agree that there should be some indication what CDI you're on. But I think even with GNS100 you are still able to fly the GPS route when setting the CDI using the clickspot.



  • @copper Aha, I found the GPS/NAV clickspot. I should have thought to put Tool Tips on to find it (DOH!). I don't normally have Tool Tips on, so it's quite possible I clicked on that without realising. And, yes, changing that to GPS does stop NAV1 working but leaves NAV2 working, which explains exactly what I was seeing. Thank you for your patience explaining 🙂

    I haven't tried following a flight plan with the GNS100 GPS yet but I'll give that a go.



  • Glad it helped!
    There's actually an FAQ entry for this issue but it is SO short that basically it won't help anybody to figure out what they're doing wrong:
    https://support.justflight.com/support/solutions/articles/17000115002-nav1-obs1-not-functional

    The FAQ should reduce the number of issues reported for users to self-help, but a one-liner not even mentioning hidden clickspots or the GNS100 topic is just plain useless.



  • @copper Agreed. I just sent them a suggestion for that.