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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Jim Moffatt on July 07, 2010, 10:53:51 AM

Title: New Super Clown E-ARF ready for flight tests
Post by: Jim Moffatt on July 07, 2010, 10:53:51 AM

I finally decided to try real Control line again. The E Super Clown is ready for flight tests. The power system is a loose copy of Alan Hahn's post in the "list your setup" thread. Motor is a Turnagy TR35-40C (2820 with Kv=1100). Prop is an APC 10x7E. ESC is a Suppo 50A helicopter control with governor mode. At 8500 rpm the static current on 3S batteries is around 26 amps. Since I fly RC a lot I am using RC throttle control. This allows mid-flight power level adjustments. The battery system is made up of 3 1/2A sized batteries in parallel, Two 3S 850 mah Hyperions, and one 3S 500mah Turnagy for a total of 2200 mah. All are rated 20+ C. The pix show the setup.

Title: Super Clown first flight
Post by: Jim Moffatt on July 16, 2010, 08:58:22 AM

Well I completed my first real control line flight in 20 years with the electric SC this morning. With 60' lines and about 8500 rpm on a 10x7 prop, lap times were about 5.0 sec. The plane flew really well and the flight was a real joy!

Title: Re: New Super Clown E-ARF ready for flight tests
Post by: ChrisSarnowski on July 20, 2010, 06:44:36 AM

Good job ,Jim!

That battery arrangement is pretty interesting. It lets you distribute the batteries around to take advance of different size open spaces.

-Chris

Title: Re: New Super Clown E-ARF ready for flight tests
Post by: Rob Swider on July 30, 2010, 10:25:35 AM

Jim,
How long was the flight time on the 2200 mah battery?  I was planning to buy the Electric Super Clown and I have a number of 2200 packs laying about, but Brodak recommends a 3300 mah pack.  Just wondering if it's really necessary to buy the more expensive 3300 mah packs...

Thanks,
Rob

Title: Re: New Super Clown E-ARF ready for flight tests
Post by: Jim Moffatt on July 30, 2010, 07:36:08 PM

To be safe I limit the time to 4 min. This is a little shorter than the usual 6 min but I am a beginning level flier.

Here is my math. A 2200 mah pack will deliver 22 amps for 6 min. When delivering  26 amps the time is reduced to
(22/26)*6= 5 min. To keep from completely discharging the batteries I stop at 4 min. This keeps the batteries from getting hot and allows many recharge cycles.

The actual average amp draw in flight is less than 26 amps so my calculation is conservative. For full 6 min flights I would use a battery around 2600 mah.

I hope this helps.

Title: Re: New Super Clown E-ARF ready for flight tests
Post by: Rob Swider on July 31, 2010, 07:41:38 PM

Quote from: Jim Moffatt on July 30, 2010, 07:36:08 PM

I hope this helps.

Sure does.  I get dizzy fairly quickly, so I set the timer for 1-2 minute flights anyway. ;D 

Thanks,
Rob