- May 30, 2020
- Reaction score
I was thinking only of the aerodynamic forces during boost, not during low-speed ( gliding ) flight.The wing downwash may be a bit lower than you think. If you want to move the stab farther from the downwash effects, move it up with a T-tail. Lowering the stab simply keeps it farther from the motor exhaust.
Getting stab out of wing downwash makes alot of sense. I thought it maybe had something to do with high wing planes being mor stable because of what was called pendulum effect.Nowadays many gliders use a CF tube for a fuselage and adding a “shark head” to raise the wing is extra work for something that will probably fly away in a booming thermal.
I did it anyway to get the rear stabilizer out of the wing turbulence and to provide a place to mount a silly putty dethermalizer timer to “pop” the wing up. In the old days, we used D/T fuse and rubber band system.
Most gliders now also use an underslung vertical fin and dihedral in the rear stab.
Correct about being weaker. Anyway I haave never seen a T tail either. And besides it would have to be on the BOTTOM of the boom so it wouldn't get burned.I was thinking only of the aerodynamic forces during boost, not during low-speed ( gliding ) flight.
As for the T-Tail, I suspect that it would be a weaker design, structurally, since the entire Empennage would only be bonded to the Fuselage at the base of the Rudder. Also, I think there would be a lot of "Torque" ( twist / flutter ) acting on the Rudder itself. It would be subject to the "double-whammy" of airflow and exhaust turbulence.
I can't recall ever seeing a T-Tail BG or RG, design . . . ?
Has anyone ever done any Wind Tunnel analysis on Gliders, especially at high velocities, simulating Boost conditions ?
I was certainly not advocating for T tails on B/Gs, just making a counter point. However, I have seen T tails on real sailplanes.Correct about being weaker. Anyway I haave never seen a T tail either. And besides it would have to be on the BOTTOM of the boom so it wouldn't get burned.