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Old Apr 14, 2012, 04:55 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
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need an application for this...

hey guys. i have a new 2s 1000mah lipo that was originally for my car, but is extremely boring to run. so, i would like to put this battery to use in an aircraft; either plane or heli. are there any planes or helis out there that will be able to use this battery? i've been searching but all the ones i look at seem to use 3s lipos instead of 2s.
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Old Apr 14, 2012, 05:00 PM
Fly it like you STOL it!
Endlesslag's Avatar
USA, VA, Spotsylvania
Joined Jan 2011
4,003 Posts
Try a superfly
www.superflyrc.com
They're fun flyers and darn near indestructible
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Old Apr 14, 2012, 05:39 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
4,405 Posts
thanks for the suggestion. i will look into that. anyone else have a suggestion?
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Old Apr 14, 2012, 05:53 PM
Shelter Kitty "Orange Death"
bartricky's Avatar
United States, FL, Monroe
Joined Jan 2008
3,157 Posts
+1 on the SuperFly, most fun you can have on a 2s...

A lot of these will fly well with a 2s.
http://www.mountainmodels.com/index.php?cPath=25_151

Or any RTF that comes with a nicad should work with a 2s.
example: Wild Hawk, Easystar.
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Old Apr 14, 2012, 07:08 PM
Registered User
United States, NJ, Lodi
Joined Jan 2012
968 Posts
I run 800 2s up through 1300 3s on this so as long as you can make yours fit it should be fine.
http://www.lazertoyz.com/shop/Planes/minipopwing.htm

Use the fast set kit. Loving this wing as a quicky pull out of the car at parks.
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Old Apr 14, 2012, 07:18 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
4,405 Posts
okay cool thanks guys!
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Old Apr 14, 2012, 08:39 PM
Fly it like you STOL it!
Endlesslag's Avatar
USA, VA, Spotsylvania
Joined Jan 2011
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Have you flown before?
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Old Apr 14, 2012, 08:41 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
4,405 Posts
yes i have. i have only flown micros though...the ember 2, champ, and micro t-28.
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Old Apr 14, 2012, 08:43 PM
Just having fun
Fredriksson's Avatar
United States, KY, Hopkinsville
Joined Feb 2008
2,089 Posts
Here is some info for digestion. I have a couple of planes that I fly on 2S LiPo. The thing to know is that when running 2S LiPo the motor is the determining factor. Motors are rated in kv which is the RPM/volt. So, to take a plane that is meant for 3S and running it on 2S will work but the prop will be turning 1/3 slower theoretically. It can depend on prop and some other things, but right up front it is known that the motor will turn slower on 2S than it does on 3S. So what you need is a higher kv motor to run 2S. I would suggest 1600kv to 2600kv. Here are 2 of them from HeadsUpRC.

This Power Up 250 Sport Outrunner Brushless Motor is a 2400kv motor. It is intended for use on smaller planes up to 10 ounces.

If you are going for a bigger plane the Power Up 400 Zoom Outrunner Brushless Motor is a 2200kv motor. It can be used for a plane up to 20 ounces or so.

Where you run into difficulty with 2S LiPo is the amps. For a given plane it requires a certain amount of power to fly. The unit of measure for power is watts. Watts is Volts X Amps. So, for a given number of watts, if you drop the voltage then the amps have to go up to get the same watts. That is the reason for going to 3S or 4S or more LiPo's - to get the amps down. With the watts formula, if you increase the voltage then you can drop the amps for the same wattage. Of course, when you take the volts up then you will need to get a motor with lower kv to keep from over spinning the prop. There is a lot of room here for fudging but you normally will not see a 2200kv motor on 5S LiPo except, perhaps, for some very specialized applications. But, getting back to my point, what you have to worry about is amps.

You do not state the C rating on your 1000mAh LiPo but I would think that it would be at least 10C. At 10C that 1000mAh LiPo should be able to handle 10 amps. With that, we now know the watts you should expect to be able to generate. Watts is Volts x Amps so 7.4V x 10A = 74 watts. In this case you should be looking for a plane that can fly on 74 watts.

A general rule of thumb is to consider the watts per pound on an aircraft. There is lots of room for fudging but many will consider the following to be pretty close to reality.

35 watts-per-pound - airplane is typically hand-launched and won't do much more than just fly around
50 watts-per-pound - airplane is hand-launched, would ROG off of hard surfaces, and perform mild aerobatics
75 watts-per-pound - airplane would ROG off of a grass field, climb well, and perform nice aerobatics
100 watts-per-pound - airplane would nearly go straight up, can handle all the aerobatics.
150 watts-per-pound - enough power for 3D style of flying.

So, in your case, if you are shooting for 50 watts/lb then your plane can weigh up to 1.5 lbs or 24 oz. Or, if you want a little more power you would shoot for 75 watts/lb in which case your plane could weigh up to 1 lb. or 16 oz. The weight would be the AUW (All Up Weight) which is the weight of the plane including the battery - the full weight that will be in the air when flying.

A good place to start if you are just getting into fixed wing flight could be the GWS Slow Stick. It is a great 3 channel trainer. At $28 it is pretty inexpensive. Add on the Power Up 400 Zoom motor, an 18 amp ESC and a 7x3.5 prop and you would be good to go. Max amps would be closer to 15A but if your 1000mAh LiPo is 15C or higher, it can handle it. And with a Slow Stick you will not be using full throttle much. You would also need 2 small servos for the build.

Now, having gone through all of this, if you got all of the above at HeadsUpRC you will have spent $69 plus shipping. There would be a few minor items needed like a motor mount and glue and perhaps connector for the ESC. And if you are moving from surface vehicles to aircraft you would need a different transmitter. I would recommend the Spektrum DX6i. You can often pick them up here at RCG at a decent price. If you do not like flying you can just sell the DX6i here at RCG for about the same price you paid for it.

Good luck. I hope I did not throw too much at you.

Freddy
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Old Apr 14, 2012, 08:46 PM
Just having fun
Fredriksson's Avatar
United States, KY, Hopkinsville
Joined Feb 2008
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Quote:
Originally Posted by electricrc68 View Post
yes i have. i have only flown micros though...the ember 2, champ, and micro t-28.
Oops, I missed this. You may want to go for the GWS E-Starter at $35 instead of the Slow Stick. The E-Starter is 4 channel but would fly on the same power system. My E-Starter flys on 2S.

Freddy
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Old Apr 14, 2012, 09:23 PM
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Joined Jan 2012
183 Posts
my guanli p51 mustang runs on 1k mah
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Old Apr 14, 2012, 09:27 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
4,405 Posts
thanks fredriksson for that explanation. i actually did not know about that before! oh and the battery i have is a 40c . the E-starter doesn't look that bad! i will look into that.

on1wheel01- thanks for the suggestion! i have never heard of that plane before though...
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Old Apr 14, 2012, 09:43 PM
The Sweet Aroma of 92 Octane
electricrc68's Avatar
United States, PA, Downingtown
Joined May 2011
4,405 Posts
hmm...would the hobbyzone super cub be able to run a 2s lipo?
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Old Apr 14, 2012, 09:45 PM
Art Schmitz
United States, TN, Crossville
Joined Jan 2012
392 Posts
+1 for the SUPERFLY !
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Old Apr 14, 2012, 10:29 PM
Registered User
Livermore, CA
Joined Sep 2004
8,577 Posts
The GWS E-Starter in EPO foam would be good for a 2 cell with the 350 motor.
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