FallingWithStyle
Jan 02, 2005, 05:31 PM
Yes, g2, not g3. :(
I'm trying to model the Hell Raiser in G2. Its a 13-14oz foam bi-plane. I've entered all of the dimensions for the plane taken from my actual model. I had to create a new motor entry for an AXI 2208/34 and I used the actual spec sheet to set the parameters. The AXI docs don't specify kT but a value of 2 gives the plane the pep that I've experienced. The cg is at 3.5" as recommended.
So my model simulates climb and axis rates pretty accurately. However, I can't get good simulation of the HR's low speed high alpha stability or its knife edge capability. The plane simply tip stalls and snaps violently when the plane slows down or when I enter knife edge and try to push the nose skyward with the rudder.
I've experimented with all of the symmetrical airfoils for the main wings but only the fattest naca 0016+ allow any slow flight at all. G2 can't handle a real flat slab main wing at all. I think I've got an accurate sweep back setting of 9.5 degrees. Incidence is at 0 for both wings just because I can't see any real angle on the actual model.
So any aero engineers out there that can help me get the g2 model to behave? What parameters are effecting these stalls during knife edge and slow speeds?
Thanks
Clark
I'm trying to model the Hell Raiser in G2. Its a 13-14oz foam bi-plane. I've entered all of the dimensions for the plane taken from my actual model. I had to create a new motor entry for an AXI 2208/34 and I used the actual spec sheet to set the parameters. The AXI docs don't specify kT but a value of 2 gives the plane the pep that I've experienced. The cg is at 3.5" as recommended.
So my model simulates climb and axis rates pretty accurately. However, I can't get good simulation of the HR's low speed high alpha stability or its knife edge capability. The plane simply tip stalls and snaps violently when the plane slows down or when I enter knife edge and try to push the nose skyward with the rudder.
I've experimented with all of the symmetrical airfoils for the main wings but only the fattest naca 0016+ allow any slow flight at all. G2 can't handle a real flat slab main wing at all. I think I've got an accurate sweep back setting of 9.5 degrees. Incidence is at 0 for both wings just because I can't see any real angle on the actual model.
So any aero engineers out there that can help me get the g2 model to behave? What parameters are effecting these stalls during knife edge and slow speeds?
Thanks
Clark