Hard to phrase but ,it seems like there is some kind of ratio of " cargo capacity to duration of flight" Our P2's seem to do, say, 20 minutes at 1200 grams or 400 grams per hour if it is ok to express it that way, is this just a brick wall in general or is there obvious ways to increase flight time that is not occurring to me. I am sure there is some tweaks as DJI has not reached to the top shelf for components. Even if we grabbed the best batteries and the lightest airframes there would be a wall and how will we get past it, is the technology just not available for this hobby get to 40 minute and then 60 minute flight times. Is there a rule of thumb someone knows of ??