Board index FlightGear Development Aircraft

McDonnell Douglas MD-11

Questions and discussion about creating aircraft. Flight dynamics, 3d models, cockpits, systems, animation, textures.

Re: McDonnell Douglas MD-11

Postby Octal450 » Tue Jun 28, 2016 10:31 pm

@legoboyvdlp
Thanks alot. :)
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby ph-cor » Thu Jun 30, 2016 11:48 pm

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
ph-cor
 
Posts: 16
Joined: Tue Aug 19, 2014 5:46 pm

Re: McDonnell Douglas MD-11

Postby Octal450 » Fri Jul 01, 2016 12:03 am

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
Last edited by Octal450 on Thu Feb 15, 2024 8:42 am, edited 1 time in total.
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby ph-cor » Fri Jul 01, 2016 10:11 am

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
ph-cor
 
Posts: 16
Joined: Tue Aug 19, 2014 5:46 pm

Re: McDonnell Douglas MD-11

Postby Octal450 » Fri Jul 01, 2016 12:06 pm

:)

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
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby Octal450 » Tue Jul 12, 2016 2:08 am

@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,
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby tikibar » Wed Jul 13, 2016 2:20 am

@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
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)
User avatar
tikibar
 
Posts: 545
Joined: Mon Mar 05, 2012 7:05 am
Location: Los Angeles
Callsign: CHT0009
OS: Ubuntu 14.04

Re: McDonnell Douglas MD-11

Postby Octal450 » Wed Jul 13, 2016 3:23 am

@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
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby tikibar » Wed Jul 13, 2016 8:20 pm

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.
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)
User avatar
tikibar
 
Posts: 545
Joined: Mon Mar 05, 2012 7:05 am
Location: Los Angeles
Callsign: CHT0009
OS: Ubuntu 14.04

Re: McDonnell Douglas MD-11

Postby Octal450 » Wed Jul 13, 2016 8:23 pm

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
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby Octal450 » Thu Jul 14, 2016 12:44 am

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
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby tikibar » Thu Jul 14, 2016 1:35 am

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.
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)
User avatar
tikibar
 
Posts: 545
Joined: Mon Mar 05, 2012 7:05 am
Location: Los Angeles
Callsign: CHT0009
OS: Ubuntu 14.04

Re: McDonnell Douglas MD-11

Postby Octal450 » Thu Jul 14, 2016 3:44 am

@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
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: McDonnell Douglas MD-11

Postby Thorsten » Thu Jul 14, 2016 7:29 am

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.
Thorsten
 
Posts: 12490
Joined: Mon Nov 02, 2009 9:33 am

Re: McDonnell Douglas MD-11

Postby Octal450 » Thu Jul 14, 2016 11:57 am

-
Regards,
Josh
Last edited by Octal450 on Wed Nov 25, 2020 8:38 pm, edited 1 time in total.
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5601
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

PreviousNext

Return to Aircraft

Who is online

Users browsing this forum: No registered users and 9 guests