Claude Wheelbarger wrote:
> 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 Claude, I agree that the prop wash air is moving faster that the clean air outside the prop wash. It's just that you seem to report that the 48" pitch prop creates more thrust than the 50" pitch prop that has me wondering. Any aeronautical engineers out there? Syd
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