I've been flying quadrotors for about a year now and recently tried to design one and build it up. I'm having a hell of a time with my estimated flight times. No matter what combination of motors and props, I can't get my average flight time over 7 minutes. My plan is to make a multirotor that can carry FPV gear and a GoPro (maybe Gimbal) for around 10-15 minutes. Does anyone have special tips on maximizing flight times? Is this sort of flying time even achievable with this setup?