Hello everyone, since many drone players don't know how to calculate flight time, here MAD COMPONENTS will tell you a formula to calculate flight time and then choose the best flight time battery for your drone, hope it can help you!

Calculation formula: flight time of UAV = (battery capacity * battery discharge / average amperage) * 60

To calculate the flight time of an FPV drone, you must know three factors: battery capacity, battery discharge and average amperage, as follows.

Battery capacity: It is well known that a larger lithium battery provides more energy. In fact, the battery is too heavy instead, resulting in less flight time for the drone, but we won't discuss that today. Calculate the battery capacity in ampere-hours to convert mAh to Ah and the battery capacity divided by 1000. e.g. 1800mAh / 1000 = 1.8Ah.

Battery discharge: The alarm will inform you of the danger via the battery, which will be permanently damaged if the voltage level falls below 20% and is completely discharged. In view of this, it is common practice not to allow the battery to fall below 20% during the flight. In other words, the effective capacity is only 80% of what can be used during the flight time. For example, 1.8Ah * 0.8 = 1.44A (effective capacity). Drone flight time calculations are based on real battery capacity or non-oversized capacity.

Average Amperage: Before you do this, you must understand two things. One thing is about the carrying weight of the FPV drone, which includes the battery weight. The other thing is the parameters of the FPV drone motor, read your motor description, you must know how many amps a motor will generate to produce 100g of pull, this is the key point to calculate the average amperage.

For example, if you know that each motor draws 1 amp of current to produce 100 grams of thrust. If your FPV drone is to fly 2000g, each motor must produce 500g (500g = 2000g / 4 motors) of pull to hover. Then the average amperage of your FPV drone is 20AMPS (20AMPS = 4 motors * 500g / 100g / 1 amp).

Another way to calculate the average amperage is to buy a smart lithium battery that will record the amperage as the drone travels through the air or hovers steadily in the air, this calculation is more accurate than the first one.

Make a conclusion for the drone flight time. For example, I have an ovonic 3s 3300mAh LiPo battery, I calculate the average amperage of the drone to be about 20 amps, I assume that 80% of the battery capacity will be used, then the flight time of the FPV drone is 7,92 minutes.

Drone flight time = (3300 / 1000mAh) * 80% / 20 amps * 60 minutes = 7.92 minutes.

Obviously, the above is a very simple calculation based on stable hovering. For aerial photography work or traversing aircraft flight, the motor will have to spin faster, thus generating more current. The higher current draw will reduce the flight time and your flight time will drop dramatically to about 75% or as much as 50% of the calculated drone flight time.