if I charge a drone for 70 minutes, to get 5 minutes of flying time. how long must i charge the drone to get 2 hours of flying time

With your standard consumer drone, the best flight time you can reasonably expect is somewhere in the range of 30 minutes. But when you get into the realm of commercial drones, there are actually quite a few outliers that take long flights to completely new levels.
Explaining: safari

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