$15,000, 40,000 Mah in a 10s configuration and 60 Min flight time. Seems more reasonable than other guy who took some AA batteries (24,000 Mah) and flew for 1.5 times this amount. I know a guy building a T-Rex 700 and wants 30 min flight time. His battery pack was $2,100.00 for it.
I'm not sure, but I think the long duration flight guy in the other thread had larger propellers. Those were not AA batteries he used. They are more like the ones I have in a LED flashlight from Hexbright (http://www.hexbright.com/) which are a lot larger. I don't know what you friend got for $2,100 because I found these 3S 40,000 mAh for $999, larger S values are available. http://www.all-battery.com/browsepr...mAh-(7872185-4P4S)-(Customized)---New!!!.HTML
