Geared or not geared?
02-22-2005, 08:38 AM
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RE: Geared or not geared?
If you're drawing the same current either way, the flight times will be the same.
The reason a geared system, turning a bigger prop at a lower RPM, will give you longer flight times is because more of the motor's power is being transferred into thrust. This means you can use lower throttle levels to maintain the same flight profile, drawing less current, extending your flight time.
Think of swimming: dog paddle vs. the breaststroke. Small rapid movements == slow progress and tremendous expenditure of energy. Large sweeping movements == good speed and more distance covered for the same expenditure of energy.
The reason a geared system, turning a bigger prop at a lower RPM, will give you longer flight times is because more of the motor's power is being transferred into thrust. This means you can use lower throttle levels to maintain the same flight profile, drawing less current, extending your flight time.
Think of swimming: dog paddle vs. the breaststroke. Small rapid movements == slow progress and tremendous expenditure of energy. Large sweeping movements == good speed and more distance covered for the same expenditure of energy.
02-23-2005, 11:00 AM
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RE: Geared or not geared?
My little Alfa Models Corsair has a gearbox supplied in Uk anyway with a gearbox and Graupner 300 motor. I am using an 11.1 volt 800mah power pack and it goes superbly. I only use full power occasionally, so the thing does not get hot and flys for about 15 minutes. Mainly because the all up weight is only 11 oz. This is the first time I have used a gearbox, but it wont be the last. The little 300 sized can motor is pulling a 9 X 6 slow fly prop and will fly vertically! Prop torque has to be watched on launch. Full power will roll the thing left very fast, but once away the Corsair is so stable. When the motor you are using will procuce high revs per volt, it makes sense to use a gearbox to drive a big prop.[8D]
