While most people are focused on cleaner burning cars, there are a few who are more interested in cleaning up the skies. Randall Fisherman is one such person, and he designed what could be the first all electric fully powered airplane.
The design, called the ElectraFlyer-C , started as an accident when Fisherman purchased a motorized glider kit and assembled it. It was noisy and offered almost no dependability, which landed it in storage for almost 10 years. About two years ago, Mr. Fisherman decided to bring it out and see what he could do to improve it.
He started by removing the internal combustion engine and replacing it with an 18 horsepower electric motor that he and come colleagues designed. The next step was to increase the length of the propeller blades to 45 inches from tip to tip, which increased the amount of thrust by over half. Due to the length increase, the body of the plane had to be raised by 8 inches as well.
The team also assembled a pair of battery packs to hold two 75 volt lithium ion batteries. When fully charged, the batteries can move the plane at 70mph for up to 90 minutes. They can also be charged in mid air thanks to a unique system that allows the thrust to be turned off and the forward motion of the plane used to turn the prop. For safety reasons, each pack is surrounded in ceramic and a thin layer of stainless steel, reducing the chance of fire damage.
Since everything runs on electricity and inherently is more efficient than traditional internal combustion engines, the ElectraFlyer-C achieves and overall efficiency of 88%, as compared to a similarly powered two-stroke engine that returns only about 15%. A full charge takes about 6 hours, and according to Fisherman, costs about 70 cents per charge.
Inside the cockpit, only the things that you need to fly safely are found. A voltmeter acts as your fuel gauge and an ammeter lets you know how fast the battery is being drained. During the recharging phase, a minus sign next to the value on the ammeter means that it is recharging the battery properly.
Mr. Fisherman currently sells kits on his website if you are interested in purchasing one for yourself and he is also expecting to have a full kit, glider and all, by mid 2010.