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Old 08-11-2016, 10:24 PM
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bem
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Hi,
I think it is hard to tell an effiecient low RPM that will break more optimal.
But as I understand it:
The (slow)spinning prop act as a "disc" so when You dive You have a large disc helping slow down the plane.
Free wheeling prop will give more braking effect then a stopped prop. But a free wheeling prop will, as far as I know, increase in RPM some as You dive making it less effective as brake as RPM increase.
With ESC brake activated the prop will spinn but not increase in RPM when You are in (vertical) dive.
With most modern ECS that has brake one can set % how hard the brake is going to be. One have to experiment some how many % will give most brake effect. It is usually good to start at maybe 20% brake and work up from there to see by trail and error in flight when the brake seems to be most optimal.
I use brake in my ESC's on my F3A planes. I use Jeti/Hacker Master Mezon ESC and I use 56% brake power.

If You do not want to use ESC brake You have to experiment with various low RPM and see if You can notice any difference in how the plane might be slower at some specific low RPM on Your electric motor.
But if You have ESC brake I suggest You try that also and compare.
ESC with brake activated (at optimal brake setting) should give best braking effect on the plane.
When I land my F3A planes, that has ESC with brake and plane is on final I take the trottle fully down (so brake is activated) I can then see with my eyes that the plane slown down a little and the plane also get an increased sink rate so I must give just tiny up elevator and then flare for a touch down.

/Bo

Last edited by bem; 08-12-2016 at 04:00 AM.