PA-28R Turbo Arrow III/IV altitude hold

[antonvs]

Hi, updated to v0.5.5 and with SU10 I'm find that when I click the click-spot to activate Altitude Hold the A/P does go into that mode but does not hold the altitude but goes into a steady climb at around 700fpm. Has anyone had this issue, I have had a search but couldn't find any posts. I tried switching off the hold then trimming either for level flight or even a steady descent, but after activating ALT HOLD, the plane starts a steady climb again. Any help please.

[HaMa]

Hi, The PA28 does not have an automated pitch. So you always have to manage the altitude manually. That is the reason why it does not have a VS Mode, too.

[antonvs]

@hama Thanks for your response.


However, this has been modelled and used to work. Attached is p.36 from the Just Flight user guide. The image is not loading, here are the options mentioned on p.36

PA-28R Turbo Arrow III/IV – Operations Manual 36

AUTOPILOT

1. Autopilot engage switch

2. Roll command knob

3. Heading switch

4. Navigation/approach coupler knob – click on the Piper label above the knob to toggle altitude hold mode. The tooltip text indicates whether altitude hold mode is engaged.

5. Coupler radio selector switch

By modern standards the AutoControl III B is quite a primitive autopilot. It controls the roll axis of the aircraft but is not equipped to control the pitch axis.

NOTE: option 4.

[HaMa]

Oh, ok. Did not realise that, my fault, sorry.
As i am in the cockpit this moment i tried that clickspot and it works fine. My plane was leveled out and as i clicked that spot. the plane shaked for a short time and holds altitude exactly now.

[Fly-Harry-Fly]

Hi! I had the same problem. When I activated the ALT HOLD mode, I had a constant sink rate. No matter if I activated the ALT HOLD mode via the hotspot or via my honeycomb throttle. I also did not know why. Then I found out the following.

When I activate the ALT HOLD mode, the aircraft holds its altitude. Then I select the V/S MODE on the honeycomb. Now when I turn the knob I can set a sink or climb rate. Of course I can set the sink rate back to 0.

Perhaps this V/S MODE is not intended and has not been implemented. There is also no possibility to activate this mode with the mouse in the cockpit. But in the background there are the parameters for the V/S mode. And you can change these parameters e.g. via the honeycomb throttle.