RCU Forums - View Single Post - Contra Rotating Propeller Drive for f3a 2m Pattern Planes
Old 05-04-2011 | 06:21 PM
  #252  
Brenner
 
Joined: Jul 2007
Posts: 806
Received 12 Likes on 11 Posts
From: Bridgman, MI
Default RE: Contra Rotating Propeller Drive for f3a 2m Pattern Planes

I've finally been able to start flying. It's still bitterly cold here in Southwest Michigan, (45 deg F / 7 deg C) but it's stopped raining and snowing, and the wind is starting to settle down as well. I'm running Tony Frackowiack's setup except that I'm running with a Hacker C50-14XL, and Thunder Power G6 65C 5000 mah packs. I'm pulling about 85 amps static, which is 15 amps above predicted. These packs are very nice. The cell resistances are from 1.1 mohms, to 1.4 mohms, and I'm charging at 25 amps. I get a full charge in about twelve minutes.

It's still very early yet, but right now things are going great. I'm running 22x20 props front and rear with a 9.89:1 gearset, and the plane is much faster than last year. It handles the wind much better. The plane is also noticeably quieter than last year as well. I know this because Mike is running the same Drive that I ran with all last year, and it has a noticeable bark that my Drive doesn't have. My plane still makes noise, but the frequency of the sound seems lower, so the "sound quality" is much improved. Right now I can't imagine anyone having even the slightest complaint about the noise. In fact, I think the single prop Neu setups are louder because of the Neu gearbox.

I'm pulling about 4000 mah out of my packs for the 2011 AMA Masters pattern, which is perfect. I wouldn't want to pull any more because of concerns about the life of the batteries, and I wouldn't want to pull any less, because I don't want to leave any performance on the table.

The next thing for me to try is running with the 22x18 on the front, and the 22x20 on the rear.

Brenner ...