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Trying to Decide on What Size Battery

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Old 12-01-2014, 07:08 PM
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Thunderbolt44
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Default Trying to Decide on What Size Battery

I'm now assembling my 1st Electric after years of YS & Gas. I have an Aeroworks 52" Freestyle Extra 260 ARF with a Hacker A30-12XL motor and Castle Phoenix Edge 60 esc. The box says everything but the battery weighs 54 oz. They do not say what the gross wt of this airplane is figured at. Documentation says the battery tray supports 3,4 & 5S batteries. They flew the prototype with around a 4S 2700 mah battery, but I am afraid that will give me only around a 5' flight time. The largest battery I would like to use is a 4500 mah 45c which weighs 18.1 ozs. That would give me a gross weight of say 73 ozs with a wing loading of 7.67 ozs per sq inch. It would seem I can do this. Comments and suggestions would be appreciated. Mike Nicholson
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Old 12-15-2014, 09:00 AM
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Did you select the motor and Prop? That is what will tell you how many cells to use.

What Prop are you using?


Then you need to know what the amp draw will be. If the MFG does not provide this then you need to test it with a wattmeter. I would normally recommend testing ANY set-up that was not installed by the MFG to confirm amp draw and watts.

Then we can do an estimate of the flight time at full throttle.

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Old 12-15-2014, 04:38 PM
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I think your wing loading calculation is wrong.
73 oz for 560 sq in gives 73/560 = 0.13 oz/sq in or 18 oz/sq ft.

Extra battery capacity does have a downside in that the plane is heavier so it need more power (and thus use more battery capacity) to fly. Add too much extra weight and the plane's handling can be impaired as well.

You are using the recommended motor and ESC so I would suggest using the recommended battery (2600mAh 4s) as well at least to start with.
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