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Old 03-13-2015, 03:46 AM
  #35  
FlyWheel
Ochroma Pyramidale Tekton
 
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Location: Blackstock, South Carolina
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OK, I ran those through and for a 10 X 6 and I got:
Possible Aerodynamic Problems:

The static pitch speed (40mph) is within the range of approximately 2.5 to 3 times the model's stall speed (15mph), which is considered ideal for good performance.

Aerodynamic Notes:

With a wing loading of 8.7oz/sq.ft, a model of this size will have very sedate flying characteristics. It will be suitable for relaxed flying, in calm or very light wind conditions.
The static thrust (23.4oz) to weight (32oz) ratio is 0.73:1, which will result in very short take-off runs, no difficulty taking off from grass surfaces (assuming sufficiently large wheels), and steep climb-outs.
At the best lift-to-drag ratio airspeed, the excess-thrust (14.4oz) to weight (32oz) ratio is 0.45:1, which will give steep climbs and excellent acceleration. This model should be able to do consecutive loops, and has sufficient in-flight thrust for almost any aerobatic maneuver.
An 11 X 6 gave me this:
Possible Aerodynamic Problems:

The static pitch speed (37mph) is less than 2.5 times the stall speed (16mph), which may result in reduced performance at typical flying speeds and a low maximum speed. This situation is usually acceptable for an electric sailplane or other slow-flying model.
Pitch speed can be increased by using a higher pitched and/or smaller diameter propeller, a higher cell count, or some combination of these methods.

Aerodynamic Notes:

With a wing loading of 9.9oz/sq.ft, a model of this size will have very sedate flying characteristics. It will be suitable for relaxed flying, in calm or very light wind conditions.
The static thrust (29.7oz) to weight (36.7oz) ratio is 0.81:1, which will result in very short take-off runs, no difficulty taking off from grass surfaces (assuming sufficiently large wheels), and steep climb-outs.
At the best lift-to-drag ratio airspeed, the excess-thrust (17.5oz) to weight (36.7oz) ratio is 0.48:1, which will give steep climbs and excellent acceleration. This model should be able to do consecutive loops, and has sufficient in-flight thrust for almost any aerobatic maneuver.
So it appears that the 11 X 6 will give me my best results with this motor. Not as fast as the 10 X 6, but better thrust (ST of 0.8:1 as opposed to 0.7:1). Which is what I want; better climbing, not speed. And both are better than the 10 X 5.

And BTW 11 X 6 is the maximum not the minimum. Anything larger and the motor couldn't handle it or I risk overheating. (even with a 12 X 4). Good thing I hadn't bought the prop yet!






(Remember, you recommended this motor!)
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