Greg, thanks for the link. Per that link, they were siting 3-4 amps draw for on OS f plug. That would validate my test better than the 1.5-2.2 amp draw assumption.

With this knowledge I think what I will do is make two of these battery packs and use one pack for 2-3 flights then drop in the other for more flights while the other is charging. After 4-5 flights I am pretty much done for the day anyway.
ScaleME