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Old 05-09-2022, 09:34 AM
SAP_2000's Avatar
Join Date: Apr 2003
Location: Stabekk, NORWAY
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Thanks Agrav8ed

I maddened it yesterday. CG was at 170 mm or center of wing tube. I will keep it there but don't recommend to go further back. Rotates and lands well, and as i guessed, around half of the elevator throws was needed. I'm at about 1" elevator throw now and even that is on the responsive side.
Ailerons was ok too.

The plane flew very well. 4-point rolls and inverted it behaved beautifully and very neutral as i like it.

But the brakes, has someone gotten them to work at landing speeds? I am very happy i flew at a full size airport yesterday with plenty of runway.
The brakes grip fairly well at stand still and low speed (up to 10-15 mph). But above that the braking force is zero (and i mean zero).

Pulling the wheels off i see that there is no physical contact between the brake "drum" and the wheel itself. Not like other designs using a dick with or without brake pad material.
This brake purely relies on electromagnetism with no physical friction and i can't understand how this could work at higher speeds even in theory. Yes magnets are powerful, but in my experience they need to be close and not moving/ rotating.
This surprises me, with JP who makes a lot of LG sets for many popular jets, and i guess we should be reading about JP brake issues on every forum and FB group. For me, this is the first i seen or heard about it.

And my question is what have you guys done? Or did your brakes work well? If so, are they the same design as mine?
I have the JP brake controller with the 2 adjustable pots and its running on 2S (2-6S specified)

Please see the attached pics.