RE: Astro 05 Battery?
The current draw is a factor of the prop your using. Assuming a 7-4 or a 8-4 prop, your looking at 20 to 25 amp draw. Check it though. Your 3s pack puts out 11 volts, but what amp draw can it support? If your talking about etec 1200, its 7 amps. So you have to put 3 or four packs in parallel to support the current draw.
Hope this helps.
John Pursell