First low battery level warning came at 11:37 at 30 percent battery. My whole flight lasted 14.50 minutes down to 10 percent battery power, thats when i powered off, and from this time 40 seconds was on the ground with the motors spinning in idle. Is this considered a normal flying time with the TB47 battery? I know they say about 15-18 minutes, but is that down to 0 percent battery or how do they count? Does anybody even get 18 mins or even 17 mins from a TB47 battery?