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McDonnell Douglas MD-11

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Re: McDonnell Douglas MD-11

Postby tikibar » Mon Oct 31, 2016 3:51 am

Sorry, I've been away for a bit. The AFDS controller has a property already to activate the autoland. It would be better to put the listener on that property: /autopilot/autoland/engaged. Right now, that activates at 200 ft agl, but that is easily changed to 150 ft (see AFDS.nas, line 396).

For the mach with pitch, I haven't had a chance to do any further testing, but the main problem I noticed was on switching from IAS to Mach mode and then adjusting the mach. The pitch didn't drop below 0, but the VS did. In general, the speed should change fairly gradually in response to changes to the commanded speed (or mach). It shouldn't pitch down too much. We're in a passenger liner, not a military jet.

I'm a little skeptical (without having tried it) about scaling the mach up by x1000. The IAS values we're dealing with are in the range of 200-300 (approx), so 865 is pretty far above that and the PID controller is likely to react differently to that high a value.
Boeing 747-8 (rename folder to 747-8i)
Boeing 757-200/300 (rename folder to 757-200)
Boeing 767-300/ER (rename folder to 767-300)
McDonnell Douglas MD-11 (rename folder to MD-11)
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Re: McDonnell Douglas MD-11

Postby Octal450 » Mon Oct 31, 2016 12:40 pm

Hmm.

It seemed to work for me.

I am going to be building a new FLCH controller which sets Vertical speed first, then from VS to pitch degree, that way I can limit it in the umin umax by VS, not pitch degree. This should also help with Mach.

I found another issue. Velocities/Mach doesn't update very often. I'm going to use instrumentation/airspeed-indicator/indicated mach instead. That may have caused the agreesiveness.

I'll check it the autoland stuff, thanks.
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Re: McDonnell Douglas MD-11

Postby Octal450 » Thu Nov 24, 2016 3:23 pm

I found the issue with Mach by Pitch. IAS by Pitch is on a 10 second predictor, while Mach isn't. I corrected this in my IT-AUTOFLIGHT, and it works much better. I've pushed it to my repo for the MD-11. It might need a little more tuning, I will do more testing.

What a stupid mistake :mrgreen:

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Re: McDonnell Douglas MD-11

Postby AtlasV541 » Sat Dec 23, 2017 8:09 pm

Hi everybody, I'm flying Dogsaymoo's version available on Github. Can anyone tell me if it has autoland? If so, how to use it?
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Re: McDonnell Douglas MD-11

Postby Octal450 » Sat Dec 23, 2017 9:06 pm

It does not. (well, it kind of does, but it doesn't work properly, or realistically right now)

But the IDG version does: http://www.github.com/it0uchpods/IDG-MD-11X.git

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