'Nose Down' attitude in cruise: wing curve(s), Basic drag, CoG location, Elevator efficiency.

[dany93]

Issue-5
(For tests, no Pull request)

See this message https://forum.flightgear.org/viewtopic.php?f=4&t=28303&p=344271#p344270 in the forum for a description of changes and test results.

Wing incidence: The initial FDM was <wing_incidence> 0.0349 </wing_incidence>
which obviously is a mistake, because the default units are degrees. I guess Erik meant 0.0349 rd = 2 deg. But written like this, it comes to almost to 0°.
As I found nothing on this subject, I set it at 0, waiting for better. We will see what Alan says, and how he solves the question.

I have calculated and added a extended propeller file (prop_74in_2f_NACA_10-30deg-65hp.xml), adding an extrapolated curve between 15 and 10 deg for tests. Less reliable than the interpolated part, but IMO not too bad if we don't go down too far from 15°. Finally, it seems that we don't need it.

[wlbragg]

@dany93 I pushed a small change that eliminates the geodinfo call. It is expensive and not being used anyway. I didn't want it to interfere in anyway with testing.
EDIT:
Or so I thought I had. You pushed a change before mine and I didn't pick it up so mi push failed. It's there now.

[wlbragg]

I'm going to continue to push any changes to this branch as well as the master branch so as to be able to test in "like" environments.

[wlbragg]

@dany93 I accidentally deleted the test branch Issue-5. If your still using it maybe you can restore it from your local.

[dany93]

Not important.

I no longer work on it, I feel that Alan is doing a very good and much more profound work on it.

Initially, it was for you and Alan if you wanted to test it or see the Lift curve that I proposed.

Tell me if you prefer, I can restore it.

[dany93]

If your still using it maybe you can restore it from your local.

Done.
Just as a backup and keep it available.
It will probably to be deleted at the end.