(February 2011) — It has been seldom in the history of aviation that a single technology has revolutionized the way we fly by addressing multiple problems facing the industry and solving them all. The most important such event was the widescale adoption of the turbine engine in the 1940s. Turbines, as you know, remedied (and continue to remedy) commercial, military and business aviation problems of reliability, cost, range, speed and power, while also bringing with them a number of infrastructure advantages associated with using a single fuel type.
Though it's still in its infancy, electric propulsion seems to promise to solve a similar range of problems in light GA. But in the case of the electric motor, the potential advances might be more sweeping and more compelling, though almost certainly on a smaller scale economically.
The most visible electric airplane project these days is Bye Energy's Green Flight Project. The man behind the program is George Bye, an engineer whose background as an Air Force transport pilot and instructor doesn't seem to lend itself to his new role as a high-tech entrepreneur and self-described futurist, the head of a company that is trying to do no less than bring electric power to the mainstream of light general aviation.
Bye has even bigger ideas for Green Flight, but the first step for his company is nevertheless an ambitious one: to convert the most popular airplane in history, the Cessna Skyhawk, to electric power. On Bye's team is a guy who certainly knows Skyhawks, former Cessna CEO Charlie Johnson. Bye and Johnson gave a product update on the Green Flight Project at a press conference during the AOPA Summit in Long Beach, California, in November. There was much promising news, including endorsements and partnerships with several industry heavy hitters, such as Jeppesen and Cessna. Now nearly done with the detailed engineering phase of the project, Bye Energy could be flying the first electric Skyhawk soon.
Skyhawk as Platform
While some might argue that next-generation aircraft should use next-gen airframes, Bye argues that the Skyhawk is an "ideal" platform and was chosen only after long and "careful deliberation." The airplane is the most popular model in aviation history, with more than 40,000 produced and a good percentage of those airplanes still flying. And the 172 is the model of a perfect trainer, many believe, a relatively lightweight four-seater that flies beautifully and lasts a long time.
It's hard to overstate the importance of the fact that the 172 is a certified airplane, one that has no questions surrounding it, other than those having to do with it being too safe a choice. With the airframe question out of the way, Bye can simply concentrate on what is a tough enough task, creating a safe and satisfying electric power solution.
Moreover, the company's choice of the Skyhawk infers instant credibility upon the project, something that's hard to imagine happening for a start-up purpose built electric airplane project.
A Trainer, to Begin With
The choice by Bye to focus, at least at the start, on the training market seems as well thought out as its choice of airframe. Because the current state of the electric art will limit the first "Byehawk" to about two hours' absolute endurance, the most suitable role for the airplane is that of trainer. There are good reasons for this.
Most training flights last around an hour, and very few go as long as two hours, so the projected endurance of the electric Skyhawk is workable. Just as importantly, most training flights are out-and-back affairs, so the electric trainers will be returning to their home airports to recharge, instead of having to search for a friendly source of current elsewhere.
We often think of battery weight and capacity as being the holy grail of electric vehicle progress, and that's true, but there's another key factor: recharging time. This just happens to be an area where the state of the art is rapidly improving. Bye says that, within the very near future, recharge times, which currently run at around a 1:1 ratio — that is, it takes an hour to put an hour's charge into the batteries — could soon be down to a ratio of 0.25:1, or 15 minutes for a one-hour charge. This improvement would change the game.