> Claude, now that I've had time to think about your propellor experimentation, I > think maybe you have some numbers mixed up, or that maybe this moveable pitot > tube works strangely when it's within the turbulent prop wash. If the 48 has a > much wider prop wash than the 50 and the air is moving much faster than the 50, > the plane should go much faster with the 48. After all, wider and faster gives > you many more cubic feet of air being thrust backwards. I'm no aerodynamacist, > but that's how it seems to me. > > Syd
Hi Syd Well the air within the propwash is always moving faster than the plane since the plane has drag. Like when your doing a runup.. the wider the propwash, the more of the plane is involved in the propwash. The only way the whole plane is clean of the higher speed air is while gliding. So when powered up the wider prop blew that higher speed air over a wider area of the plane. And higher speed air creates more drag on the involved parts of the plane. The 7150 only put the fusalage and tail in the propwash and my gear etc were in clean cruise speed air. The wider prop 7148 placed my gear in the porpwash. Since the propwash is faster air than what say the wingtips are experiencing whatever is exposed to it has the increased drag from the increased airspeed. Does that make any sense or am I drowning here?? (grin) Claude
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