Reading ailerons offset under AP

[Kelt760]

Hi Pete

Thanks for your tremendous work. I am currently trying to build a motorized double yoke for a Baron58 in Fs9 (and maybe later in Fsx, with a motorinzed trim wheel. The software is (and for the most part will be) written in SIOC. The trim wheel already works with and without autopilot.

The yoke will have a moving neutral position for the elevator, according to the elevator trim (trimming will move the neutal position which in turn will bring back the elevator value to 0). This is possible since I can read both elevator and trim offsets, even under autopilot.

But what about the aileron axis ? I want my yoke to turn by itself if I change heading on the autopilot (no trim here). But when under autopilot, ailerons offset does'nt move ; the only offset I could find to read ailerons move under AP is Aileron deflexion 2EA8. Is that correct ? But to be consitent when I enter or leave AP mode, I need to use the same offset when piloting manually. Is there a drawback to use this offset to pilot on normal conditions ? But do I need to take care of differential deflexions, as mentioned in a post 2 years ago ? In other terms, do you know if the Baron uses differential deflexion ?

Thanks again

Pierre, Saclay, France

[Pete Dowson]

But what about the aileron axis ? I want my yoke to turn by itself if I change heading on the autopilot (no trim here). But when under autopilot, ailerons offset does'nt move

Doesn't it? I didn't know that.

the only offset I could find to read ailerons move under AP is Aileron deflexion 2EA8. Is that correct ?

If that's what you've found, I expect so. I really don't know the innards of FS in this area, sorry.

But to be consitent when I enter or leave AP mode, I need to use the same offset when piloting manually. Is there a drawback to use this offset to pilot on normal conditions ?

Well, 2EA8 is only a read-out, not a control. And it is actually the angular deflection, in radians. In order to get that value matched up to the control inot, which is just a control value, -16k to +16k, you'll need to convert from the angle to the control value. It is probably not even linear, and will almost certainly vary from aircraft to aircraft. If you are only flying one aircraft you might need to use a look-up table with enough positions to make linear interpolation work. If you want to do it for many aircraft you've problably got a lot of work to do.

But do I need to take care of differential deflexions, as mentioned in a post 2 years ago ? In other terms, do you know if the Baron uses differential deflexion ?

Sorry, I've no idea. Try it and see. You might want to discuss this with more knowledgable folks on FS aircraft modelling -- I think there's a forum dedicated to such things over in AVSIM?

Regards

Pete

[Ian P]

I'd suggest a visit to FS Developer (http://www.fsdeveloper.com/forum/index.php) rather than Avsim, personally.

Cheers,

Ian P.