Electric Ultralights

Electric aircraft are recently on everyone's mind, it seems, but the most reasonable are the most skeptical. They bring up a lot of excellent points to suggest that it will be a while before electric aircraft are practical — if it happens at all. I don't think it will probably ever be a very practical means of propulsion for aircraft, where weight is so critically important.

Among ultralight aficionados, however, "practical" is not much of a consideration. Ultralights, which limited as they are to 254 pounds empty weight, five gallons of gasoline, a stall speed of 28mph, and a maximum level airspeed of 63mph, are most eminently impractical. Many ultralight pilots are excited about the idea of electric propulsion, partly because most of the available powerplants that are light enough are two-stroke engines, which are relatively unreliable, especially if they are not meticulously maintained and carefully operated. A reliable electric powerplant would eliminate a major cause of ultralight accidents. Two-stroke engines also put out a lot of incomplete combustion products, which bothers some environmentally-minded ultralight pilots. (Whether ultralights, or recreational aviation as a whole, contributes significantly to overall pollution is another question, and a doubtful one at that.)

The will is there to innovate on electric powerplants for ultralights, and it would probably be a safety advantage if it were carried out, but the FAA stands in the way. The 254-pound empty weight requirement is without fuel — but the FAA refuses to allow a similar exemption for the weight of batteries, even an excess weight equal to the weight of five gallons of gasoline, 30 pounds. This is a serious handicap when the weight restriction for ultralights is so severe. FAR Part 103 includes weight allowances for ballistic recovery systems and floats, but notwithstanding the safety advantages of a reliable electric motor, no similar allowance is made for battery weight.

It seems that the FAA doesn't want to think about ultralights, anyway, and ultralight pilots are inclined to keep their heads down; they remember what happened to the exemption for instruction in two-seat ultralights. Given that circumstance, I don't think this is likely to change.