http://www.designnews.com/article/CA...rid=1302801725 Based on a patented ac-induction motor from Chorus Motors, this WheelTug system takes its power from the plane’s APU and directly drives the nose wheel. It’s designed to move regional and larger aircraft on the ground at speeds up to 20 mph without running their turbines or hooking them up to an airport tug.
The resulting savings could be huge, which has enticed Delta Airlines to invest in the new technology, initially for its Boeing 737s. “Even a moderately sized fleet could save tens of millions of dollars per year,” says Walt Klein, Delta’s director of engineering, quality and training. WheelTug’s projections put the savings at $60,000 per month on a typical 737 involved in regional runs, according to Isaiah Cox, CEO of WheelTug, which is a subsidiary of Chorus Motors.
All those savings come from a variety of sources. One big one is the direct savings of burning less fuel when the turbines no longer have to push the aircraft to the runway. And there’s an indirect fuel savings, too. To account for taxi time, airlines often have to load more fuel onto the plane then they need for the flight itself. The weight of that extra fuel, if it’s not all burned on the ground, potentially poses a secondary drag on fuel economy.
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