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Dec 09, 2002, 10:56 AM
Registered User

big prop, gear drive v. small prop, direct drive

"What is achieved with the two options listed. My goal is to slow down a Partenavia, I have trouble slowing it down on final.



In a light FMA Razor, an APC 12 X 10 E prop on an 801G (3.3:1 box) slows the plane very nicely. Landing "deadstick", the big prop overrides the ESP brake and freewheels, producing a lot of drag. Just be careful to keep the nose pointed down some, so you don't stall.

- Jube
Last edited by RD Blakeslee; Dec 09, 2002 at 11:08 AM.
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Dec 10, 2002, 09:02 AM
Registered User

Turn off "brake"......

"The brake is not there to slow you down, but will actually speed you up due to the lack of "windmill"-effect.
Once brake is off, your approach will slow down, no matter what prop you use. If still an issue, go for a larger prop geared prop as mentioned before." - Pullin'

You're right, if the prop isn't big enough to overcome the brake. If it is, the prop will freewheel anyway, but the brake will slow it down and increase the drag on the airplane.

So, try it with the brake on, and, if the prop stops, turn the brake off.

- Jube
Jan 25, 2008, 03:46 AM
Houng-wen Lin
GWS4CEO's Avatar
When you need some thing really slow down, GWS IPS even give you more gear ratio choice!

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