Beechcraft KingAir 350

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IAHM-COL
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Re: Beechcraft KingAir 350

Postby IAHM-COL » Mon Aug 29, 2016 6:36 pm

D-ECHO wrote:This is what I could produce with coordinates from blender...

Code: Select all

   <metrics>
   ***
      </tank>

but still the aircraft is falling back :(



Hi D-ECHO
Try checking the CoG, and maybe add a nose-ballast?
A counterweight to keep the mass towards the nose.

Fuel? is the fuel mass balanced?
It's a trycicle, CG should be forward the main gears to avoid falling on the tail, too.
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

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LesterBoffo
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Re: Beechcraft KingAir 350

Postby LesterBoffo » Mon Aug 29, 2016 6:37 pm

Image

( need to select the 'fill these fields with the selected centers' tab button when in AC3D, red circled..)

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LesterBoffo
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Re: Beechcraft KingAir 350

Postby LesterBoffo » Mon Aug 29, 2016 6:45 pm

IAHM-COL wrote:
D-ECHO wrote:This is what I could produce with coordinates from blender...

Code: Select all

   <metrics>
   ***
      </tank>

but still the aircraft is falling back :(



Hi D-ECHO
Try checking the CoG, and maybe add a nose-ballast?
A counterweight to keep the mass towards the nose.

Fuel? is the fuel mass balanced?
It's a trycicle, CG should be forward the main gears to avoid falling on the tail, too.


This is also one where it's really helpful to physically look at the entire 3D model and estimate where the average wing airfoil's chord is located, the 'aerorp' position is the center of lift, which should reflect the highpoint of the wing's airfoil. The CG position can be close to the aerorp and should actually be a bit ahead of it, ( towards the front, but not by much as it takes some fudging.)

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IAHM-COL
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Re: Beechcraft KingAir 350

Postby IAHM-COL » Mon Aug 29, 2016 6:51 pm

yes.
Just to clarify, when I make the "directory structure" for this craft (Initial commit), I used as template a taildragger.
I never tried adjusting FDMs, and @JWocky did some fixes to rapidly make it flyable, but still the FDM was left in Raw State.

Therefore, I suspect a lot that it the plane drops on the tail right now, the CoG maybe displaced to the stern.
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

bomber
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Re: Beechcraft KingAir 350

Postby bomber » Mon Aug 29, 2016 6:53 pm

Actually that's not true.... what you have there is the centre of lift of the wing. The h-stab moves the centre of lift of the plane rearwards or forwards either in front of or behind the CoG making the plane pitch up or down.

All the h-stab does is position the aerop (planes centre of lift) directly over the CoG.... so 2 things that are moving, although one a lot faster than the other.

The aerop isn't a fixed point.... don't tell Alan he'll have a fit !
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchell

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IAHM-COL
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Re: Beechcraft KingAir 350

Postby IAHM-COL » Mon Aug 29, 2016 6:57 pm

Image

FDM: Exact this is the point where aircraft modelling switch to pure Welsh for me.
:(
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

bomber
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Re: Beechcraft KingAir 350

Postby bomber » Mon Aug 29, 2016 7:08 pm

It's a great diagram but what it's not explaining is what's happening to the plane with the centre of lift being where it is behind the CoG.

What people try and say is "the weight acts downwards at the CoG and the lift acts upwards at the centre of lift and these ballance each other out"

It sounds plausible...but it aint...cause a force down and a force up equals spinning, no matter how you look at it.

There's a difference between being a aerodynamic expert and being a flight modeller.... yet again don't tell Alan, as he's very sensitive and I'd hate to waste his time.
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchell

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GabrielYV
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Re: Beechcraft KingAir 350

Postby GabrielYV » Mon Aug 29, 2016 11:22 pm

This plane has no external sound??

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IAHM-COL
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Re: Beechcraft KingAir 350

Postby IAHM-COL » Mon Aug 29, 2016 11:24 pm

GabrielYV wrote:This plane has no external sound??

AFAIK you were pushing such fix :)

viewtopic.php?f=15&t=708&start=60#p12445

and

viewtopic.php?f=15&t=708&start=70#p12450
GabrielYV wrote:Hello @IAHM-COL
1. New Effects
2.Add Lights
3.add announcements
4.Add some Sounds
5.Fix and New Views
6.among other little things :)
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

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Re: Beechcraft KingAir 350

Postby GabrielYV » Mon Aug 29, 2016 11:47 pm

Thanks, clear :) I thought it was because of my simulator. ;)


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