>A bonus: The airplane can regenerate energy during braking, just as electric cars do. When the pilot slows down or descends, the propeller becomes a windmill,

>A bonus: The airplane can regenerate energy during braking, just as electric cars do. When the pilot slows down or descends, the propeller becomes a windmill, running the motor as a generator to recharge the batteries. In the sort of airport traffic pattern typical for general aviation and student-pilot training, this energy savings comes to about 13 percent. In other words, if a plane lands having apparently used 8.7 kWh during the flight, it has actually used 10 kWh⁠—the propeller-recoup system put back roughly 1.3 kWh while flying in the traffic pattern.