Jun 30, 2012, 08:53 PM 608 km/h! Australia, QLD, Toowoomba Joined Jan 2010 3,915 Posts Sorry guys, what is Longditudinal dihedral? Is this decalage or something different?
Jun 30, 2012, 09:41 PM
Just fly it!
Cody, WY
Joined Nov 2007
6,916 Posts
Quote:
 Originally Posted by josh18 Sorry guys, what is Longditudinal dihedral? Is this decalage or something different?
Decalage traditionally refers to angle difference between the two wings on a bi-plane. Longitudinal dihedral is the angle difference between the wing and the tail plane.

So if the wing was +0.5 degrees to the datum line of the fuse and the stab is at -0.25 degrees the longitudinal dihedral would +0.75 degrees.

The word "decalage" has become widely used in place of longitudinal dihedral....so use whatever you want.
Last edited by wyowindworks; Jun 30, 2012 at 10:00 PM.
 Jun 30, 2012, 09:47 PM was geht , müssen unten kommen United Kingdom, London Joined Dec 2010 6,967 Posts i'll change the wings Dihedral to 1 degree and leave it at that.... Posted from the Dreamfactory Keenan
Jun 30, 2012, 10:12 PM
Just fly it!
Cody, WY
Joined Nov 2007
6,916 Posts
Quote:
 Originally Posted by k.smith459 i'll change the wings Dihedral to 1 degree and leave it at that.... Posted from the Dreamfactory Keenan
For a DS plane you are better off putting the wing and zero and the tail plane at -1*.

Many people put them at 0 - 0......0 degrees longitudinal dihedral and then use elevator trim to trim the plane.

To optimize the rigging you want to first calculate the planned DS speed objective, then calculate the circle circumference for your site. Using this you can calculate the g-load on the wing for your approximated glider mass. Using this you can calculate the required CL (lift coefficient) of the wing. Then using your air foil and planform you calculate what AoA the wing must be at to generate the required CL. The wing would be put at this angle compared to the zero lift line of the fuse. The pitching moment of the wing at this CL would be calculated and the stab would be positioned at the correct AoA to counter the pitching moment of the wing (this is variable depending on the CG).

In the end the whole calculation is an approximation because changing the CG or ballast would change the optimum rigging.
Last edited by wyowindworks; Jul 01, 2012 at 12:12 AM.
 Jul 01, 2012, 12:10 AM U down with EPP? Ya u know me United States, CA, Ventura County Joined Sep 2008 3,291 Posts You will most likely have to shim your stab after a few test flights to get it perfect, unless of course your calculations are perfect!
 Jul 01, 2012, 01:48 AM 608 km/h! Australia, QLD, Toowoomba Joined Jan 2010 3,915 Posts Was going to say the same thing! Thanks Adam
 Jul 01, 2012, 08:28 AM was geht , müssen unten kommen United Kingdom, London Joined Dec 2010 6,967 Posts Okey doke ...
Sep 20, 2012, 09:53 AM
was geht , müssen unten kommen
United Kingdom, London
Joined Dec 2010
6,967 Posts
Well ive been away from this project a While.. and now im finally getting back to work on the Raptor
i have attached some images of the fuse plug... (not completed yet.. )
I will Continue work on the Raptor On Saturday When i will Be hotwiring the Wings
K