McDonnell Douglas MD-11

[Octal450]

@legoboyvdlp
Thanks alot.

[ph-cor]

to:legoboyvdlp
About cruising nose down.
This is caused by a too high value (0.20) for the camber setting of the wing. I have set the value at (minus 0.05). What the problem solved.
Compare it with the camber setting for the MD-10 (minus 0.1).
Hoping to see 411 among us

Kind greetings,
ph-cor

[Octal450]

OK, I can't leave the MD-11 MD-88 MD-90 without finishing some stuff

ph-cor, i changes this, and pushed, i urge you to try

The new Ecam is there too: www.github.com/it0uchpods/MD-11

[ph-cor]

Hello it0uchpod,

I am glad you stay partly in.

With the +0.05 for camber there is still a little nose down at high speeds.

Camber must be a negative value -0.05 as I have tried to propose.

I saw the ecam values in the configuration monitor. Maybe you can make the values better readable by make them brighter.

Thanks,
ph-cor

[Octal450]

Ok, I did no see minus, sorry! fixed and pushed.

which ecam? I only redid the engine (left) one (EAD_1_GE) for now

cheers

[Octal450]

@tikibar
Perhaps we can half the input of the controls using filters? If you half the axis of each axis, it should be OK. I plan to make an LSAS for it, and I will install my working FLCH system and FADEC from IT-AUTOFLIGHT.

Then I think I'll start with the thrust limits.

Regards,

[tikibar]

@it0uchpods
I made a couple of syntax fixes to the EAD so the "CONFIG" light goes off when the aircraft is properly rigged for take off. I've also tried out the updated FDMs, and they seem fine to me.

I'm not a big fan of the idea of putting limiters on the ailerons or rudder. That would potentially make the aircraft unable to handle crosswind operations. It might also require re-tuning the AP. For the elevators, it's possible to add a linear limiter directly in the FDM, without having to use AP filters. I added that on the pax version, if you want to give it a try. It limits the elevator controls at 70%. I haven't tested it at all.

I'm interested to see how your FLCH system works. Thanks!
John

[Octal450]

@tikibar
Yep I didn't have time to finish that light, thanks.

True, but it handels a bit to sensitive for an MD-11. I changed the drag on the ailerons previously, and got it very close to the real sim. I can try to do that again if you want and see how it goes.

I'll try the elevators tomorrow.

You can try the beta out in IT-AUTOFLIGHT. It works nicely in my A346VIP, MD-88 and MD-90. I still need to fix the transitions, and the increase speed thing. (10kt, then 10kt then 10kt works well) I will probably limit the pitch using vertical-speed-fpm. no less than 100fpm climb, no more than 100fpm des.

My GitHub

Regards,
Josh

[tikibar]

Might as well give it a try! As long as we can maintain the flight envelope and still stay upright in a crosswind, I'm happy.

[Octal450]

Yup, try to go to 10000ft, and push full left or right. In less than 10 seconds, its upside down. I don't think it needs to be that fast. I'll give it a try.

Cheers,
Josh

[Octal450]

John,

ph-cor fell out of the sky somehow. He reported no aileron Control

Something must be wrong.

I have not pushed my changes yet, when you added the limiter (merged to my repo), did you modify the ailerons??????

Josh

[tikibar]

I didn't touch the ailerons. I don't know of anything that would disable them. In my other aircraft, the control surfaces are tied to the hydraulics, but I haven't gotten to that system yet on the MD-11.

I made two flights today (one pax, one freighter) with no problems, and the ailerons acted as expected.

[Octal450]

@tikibar
Hmm OK,

I'll do the Hydraulics then. In the process of doing it for my MD-88/MD-90, so it seems fitting lol.

I'll ask ph-cor next time I see him, it's possible he still had the version with those aileron things we tried.

Best,
Josh

[Thorsten]

Perhaps we can half the input of the controls using filters? If you half the axis of each axis, it should be OK.

I'm not a big fan of the idea of putting limiters on the ailerons or rudder. That would potentially make the aircraft unable to handle crosswind operations.

The physical range of airfoil deflection is likely there for a reason, which is that it's supposed to be accessible under extreme circumstances. But nothing requires the FCS to map the full control range to full deflection range under all conditions (that can e.g. be Mach-number dependent) and nothing requires the AP to ever utilize the full control range - you can leave a range [-1:1] open for manual operations and make the AP utilize only a range [-0.5:0.5], assuming for all extreme situations manual takeover is required.

The Shuttle has huge elevons designed to work in the rare hypersonic airstream, once subsonic the full deflection gives insane moments - effectively in the subsonic regime you fly within a range of [-0.1:0.1] of full deflections and the FCS has correspondingly reduced gains. The AP has even more reduced gains as the needed amount of maneuvering on a nominal trajectory is little.

So just make the AP not utilize the full range of the controls and the problem is solved.

[Octal450]

@Thorsten
The issue is it hand-flies wrong. I know, I've flown a real MD-11 sim. MD-11 is quite heavy on the controls, watch any cockpit landing video, and watch how they adjust the yoke. Right now, it flies about like a A320, with FBW. I previously corrected this, in the old FDM. I'm working on doing it now. The FCS will be new, so the spoilerons work correctly, instead of mapped to the ailerons. It will be all controlled by the hydraulic system, so if there's no hydraulics, no controls move.

The AP worked fine with the wings done correctly.

Regards,
Josh