F4U DevGru - Check This "1"

[Bowie]

F4U DevGru - Check This "1".

Pitch in the F4U was massless and twitchy, not so for Roll.

Looked at the 'F4U-1D.lua' file, and came across this in the 'SFM'.

894            kjx = 2.25,
895            kjz = 0.00125,

Guessed Roll and Pitch Inertia, respectively, as that's about like how they act.

So added "1" to kjz:

894            kjx = 2.25,
895            kjz = 1.00125,

Set the 'X' and 'Y' joystick curves to '11' and '21', respectively.

Flies like a regular airplane now, with mass and rotational inertia in pitch as well as roll, in a proper proportion.

My biggest FM gripe, as it was untenable, in the face of the F4U's reputation as an outstanding gun platform.

 

Bowie

 

Edited October 21 by Bowie

[Bowie]

Update:

Upped the curve on the Pitch to '26'.

894            kjx = 2.25,
895            kjz = 1.00125,

Joystick Curves:

Y Axis = 26

X Axis = 11

Give it a try.

 

Bowie

[450Devil]

Yes, you are right. It does improve the handling of the Corsair in flight. Unfortunately, this simple change in line 895 also breaks the Integrity Check. So we need Mag3 to do this as an update to the F4U-1D.lua in the CoreMods/Aircraft/F4U-1D folder.

Like your recommended Joystick curves. I was using my standard 25 / 25 but your 26 / 11 works much better. Thank you.

[Reflected]

It does feel a lot more heavy and realistic! I wonder if it's a typo.

[Bowie]

On 10/23/2025 at 8:46 PM, Reflected said:

It does feel a lot more heavy and realistic! I wonder if it's a typo.

"1" is too much.

Maybe half that.

 

On 10/21/2025 at 7:46 PM, 450Devil said:

Yes, you are right. It does improve the handling of the Corsair in flight. Unfortunately, this simple change in line 895 also breaks the Integrity Check. So we need Mag3 to do this as an update to the F4U-1D.lua in the CoreMods/Aircraft/F4U-1D folder.

Like your recommended Joystick curves. I was using my standard 25 / 25 but your 26 / 11 works much better. Thank you.

Wanted to see it there was a drag penalty, so put the OEM 'F4U-1D.lua' back in, and then upped the Y-axis curve to '52', a 100% increase of the stated '26'.

Actually flew rather nice, except for 3-point landings, where a lot of elevator deflection is required.

Way up on the steep part of the curve, and 'twitchy'.

 

So tried '39', a 50% increase, to flatten the curve at the higher deflections.

Really nice, both precision/gunnery and high AOA landings.

 

Flies different, more of the tail as a lever, but there is some physics there now, and the nose woggle when trimming is gone.

All-in-all a better solution.

 

So, F4U DevGru, Disregard the "1", and just work on the control harmony.

39/11: would assume a linkage ratio issue.

 

Bowie

 

 

Edited 4 hours ago by Bowie