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Floating aircraft

Good sims require good FDMs (the "thing" that makes an aircraft behave like an aircraft).

Floating aircraft

Postby CaptB » Fri Jul 10, 2020 2:00 pm

Hello,

So on the first time I used aeromatic for my B763 it would spawn not on the runway, underground, rotated along the x, y and z axis. The numbers in the generated file looked strange so I thought I made a mistake somewhere and I went through aeromatic(CLI) process again with better results this time.

The aircraft is now on the runway and positioned correctly but floating about maybe about a meter AGL(from the bottom of the NLG wheel)

Since I have no experience with Jsbsim/aeromatic at all, could someone be kind enough to tell me which values should I look at to correct this?

Thanks!
Ongoing projects(3D modelling): A320, MD-11, A350, B767
FG767: https://fg767.wordpress.com/
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Re: Floating aircraft

Postby Octal450 » Fri Jul 10, 2020 6:38 pm

That's because AeromatiC has no idea what your model is.

You need to adjust the coordinates in your ground reactions to match your Gears. (I strongly recommend changing unit from IN to M, so you can use the meters directly from Blendar!!!)

Let me know if you need closer steps.

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

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Re: Floating aircraft

Postby CaptB » Sat Jul 11, 2020 8:48 am

Thanks this worked somewhat, but it's not perfect. if I have the NLG correct, the MLG floats(although a LOT less than before), when I set the MLG to the same Z value as the NLG then that becomes correct but the NLG starts floating(also by little)

I'm obviously still doing something incorrectly, are the location values measured from the CG or what?

Thanks again for your help Josh.
Ongoing projects(3D modelling): A320, MD-11, A350, B767
FG767: https://fg767.wordpress.com/
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Re: Floating aircraft

Postby CaptB » Sat Jul 11, 2020 10:22 am

Ok I changed the CG coordinates and it's a lot better now so I suppose it just needs tweaking(jsbsim reference was helpful in understanding how this works)
Ongoing projects(3D modelling): A320, MD-11, A350, B767
FG767: https://fg767.wordpress.com/
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Re: Floating aircraft

Postby Octal450 » Sat Jul 11, 2020 3:29 pm

Hi,
Sometimes the animation doesn't match up perfectly with JSB. You should animate MLG first then adjust as needed.

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

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