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Old 09-09-2015, 06:38 AM
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iflircaircraft
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Hi guys and gals:
I've built a 60 size Super Chipmunk (based on glow).
My LHS recommended using an elite 60 motor with a 100 amp ESC and a 6s 5000Mah battery pack.
Ready to fly weight is 8lb. /688 square in. wing area.
If my calculations are correct my motor/battery will produce 1443 watts.
1443 watts on an 8lb plane equates to 180 watts per pound.
Even at 80 percent efficiency I would get 144 watts per pound.
Am I way off on my figures?
It's my first electric so please be easy on me.

Tom
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Old 09-09-2015, 10:24 AM
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Jennifer Curtis
 
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I don't think it will drop like a ball as your title suggests.
Maybe land a little fast.

Jenny
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Old 09-10-2015, 10:43 AM
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blvdbuzzard
 
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An over weight Chipmunk still lands like a trainer. This has to be one of the all time best flying planes around. I have had a handful of them over the years powered by 60, 61, 65 2s, 70, 91, 1.20fs engines.

Now if I was to put a Super Chipmunk in the air with a E setup, I would go with this setup. I have this setup in (2) planes and they fly great. One is a 60 sized low wing trainer I use as a glider tug. At 12 pounds it climbs out at 70 degrees without a problem.

Motor
http://www.hobbypartz.com/96m606-big...030-400kv.html

ESC
http://www.hobbypartz.com/07e06-proton-60a.html

Battery would be a 6s 5000mah 30-40c

Use a APC "E" prop 18x6 and you will have a plane that fly's like a 91fs on the nose. Plenty of power to climb at 88 degrees yet will land like a trainer.

Here is an online calc program to play with.

It says you will pull 1200 watts with 11 pounds of thrust.

http://ecalc.ch/motorcalc.php?ecalc&lang=en


Buzz.
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Old 09-11-2015, 03:43 PM
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iflircaircraft
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Ok, so I charged my 6s 5000mah 30c battery. Hooked up my watt meter. With an APC 15x6 E prop I was pulling 45 amps and 1000 watts. My plane is just under 8lbs. 1000 (watts)/8#=125watts per pound.
The plane should do anything I can throw at it.

Tom
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Old 09-11-2015, 07:33 PM
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Chipmunks are great flying planes. You will be happy tooling around or spins. Mine did awesome inverted spins.


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