ORIGINAL: DMichael
ORIGINAL: Ed Cregger
ORIGINAL: flatspin58
Building a old Midwest mach 1 and the plans show no right or down thrust.Hate to have to put it in after its finished.I know i put some right thrust in the tiporare i just finished.
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When inverted, right thrust becomes left thrust, thus pulling the climbing model (assume an extended vertical ascent) to the left, which torque and P-factor are already trying to do. I use zero-zero and learned how to fly the model through these shifting modes.
Buy the proper tools for setting up the model, if you do not already possess them, and setting incidence and angles will be a snap.
Ed Cregger
I'm gonna have to disagree with you on this Ed. That's just not true.
gyrocptr is right on this one and I have seen it practice. I had a gas powered Extra once with one of those screw on gas caps. The cap came loose and fuel came dribbling out. When I got it down I could see the swirl patterns around the fuse that ended on the left hand side of the vertial stab. I believe that's the main reason we need right thrust.
Not my quote but I think it explains it well:
"A propeller pushes air not just horizontally to the back, but more in a twisting helix around the fuselage (clockwise as seen from the cockpit). As the air whirls around the fuselage it pushes against the left side of the vertical tail, causing the plane to yaw to the left. The prop wash effect is at its greatest when the airflow is flowing more around the fuselage than along it, i.e., at high power and low airspeed, which is the situation when starting the takeoff run. "
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There is tons and tons of stuff that I don't know factually, so I always appreciate it if someone tells me when my thinking is wrong by conventional wisdom.
I am aware of the propeller slipstream vortex and I'm not trying to weasel out of the consequences of such a force acting upon the model. It's just that I've never seen it demonstrated in reality with the old pre ballistic and ballistic models. That does not mean that it is a false assumption. It simply means that I haven't experienced it on high wingloading, high speed models - yet.
Let's keep the dialogue going.
Ed Cregger