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發表於 2002年6月29日 02:48 AM
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Recently, I met some guys who fly F5D & F5B. Their speed is fantestic. The different between power planes & electric sailplanes are: 1. higher aspect ratio in electric sailplanes; 2. floded propeller to attain high speed during dive in e-sailplanes; 3. explosive power but limited flying time; 4. location of lifting centre in aerofoil.
E-sailplanes is a compromise in flat area due to limited or unpredictable or unreliable ascending current. Once you push the throttle, there is explosive power for the first 3-4 minutes. Basically, high preformence e-sailplanes eg. F5B/F/J are same as sailplanes with only different in floded propeller, larger fuselage for battery & much higher wing loading. So their gliding ratio is a little bit limited compare to powerless sailplanes.
Alex Chan |
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