Welcome to electric flight.

The first place I would like to point you is:

<div></div><div></div><div>EVERYTHING YOU WANTED TO KNOW ABOUT ELECTRIC POWERED FLIGHT - A free e-book
http://www.rcuniverse.com/forum/m_7100376/tm.htm

If we target a 2.5 pound plane, all up, then you want at least 250 watts for spirited sport flying. So that motor looks good.

The chart tells you EXACTLY what the amps will be based on battery pack voltage and prop, so figuring that out is easy. Assuing a 10X5 prop you will pull 28 amps at full throttle.

A 3S 2800 mah pack will give you about 5-6 minutes of full power flight or about 9-12 minutes of mixed throttle. Is that enough? Go up from there.

Don't forget to include the weight of the battery in your calculations of all up weight. Also consider the space where the battery will go.
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