The textbook solution for straight wings is that 1 degree of positive
dihedral
adds approximately .0002 to Cl, the rolling moment coefficient . This
would
be added to the Clb coefficient in the input file, since it is sideslip
that generates
the effect.
I use an old copy of Perkins and Hage, Airplane Stability and Control
to look
these things up, when I need to.
Rex
Steve Hosgood wrote:
Dave Culp wrote:
But it doesn't. Seems like an oversight to me. I'm trying to model a
'plane with almost no dihedral AFAICS and I'm not sure what to twiddle
in the .xml file to get that effect.
My advice is don't worry about it. Is there something about the way the
Colditz Glider is flying that doesn't seem right?
Yeah - it flies too well!
It's got almost no dihedral, so I'd expect it to be pretty unstable in
roll.
Having said that, and though I've never flown anything other than a
hang-glider for real, I find the c172 to be rather *too* unstable in
roll for my liking. It's not obvious to me (yet) how the effects of
dihedral are handled in jsbsim, so it's not easy to experiment with
changes in those values.
Steve.
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