Re: [Jsbsim-devel] Horizontal tail arm

[Jon S. B. <js...@ha...>]

Hi, Fabian,

 

The horizontal (and also vertical) tail arm is supposed to be the length
from the CG to the quarter chord of the tail (horizontal or vertical as the
case may be), as you stated. The only thing that is done with that value is
it is tied to a property. There is also the normalized version, which is
divided by cbar. It is not updated at runtime.

 

Maybe that should be changed someday, but that's all that happens, now. It
should not change enough normally to make a noticeable difference.

 

Jon

 

 

Hello,

In the aerodynamic model I would need to include alpha_dot effect on
alpha_tail:

dEPS_alphadot = 57.3 * (AlphaDot * LHT_CG / Velocity) * dEps_dalpha

 

For this, I need the value of LHT_CG - the distance from the horizontal tail
25% chord to the actual CG.

 

Is this parameter available? For what I understand, the parameter
metrics/lh-ft or (htailarm) is the distance to the reference CG, not the
actual CG. Is that right?

 

(The same is needed for the pitch rate (q) effect on alpha_tail).

 

Fabian