VOA标准英语2010年-Electric-Powered Aircraft Closer To Re

The drive to develop a battery to power automobiles 1, without using petroleum 2, is also behind the effort to develop an electric powered airplane.  New designs for electric aircraft were recently unveiled at the Experimental Aircraft Association's (EAA) AirVenture show in Wisconsin. While plans for electric powered passenger planes are still way in the future, sport airplanes and small helicopters powered by batteries could be on the market in the next few years.

 John Monnett is the founder 3 of Sonex Aircraft. He gets excited each time he demonstrates the capabilities 4 of his new, experimental WAIEX aircraft.

It looks like a small plane. It feels like a small plane, but it doesn't sound like a small plane.

That's because this version of the WAIEX is not powered by a combustion 5 engine.  It's uses batteries. 

"We wanted to stimulate 6 thought about electric airplanes, and this is really the culmination 7 of that," said John Monnett. "It's ready to fly, it's a completely autonomous 8 electric airplane now, meaning that it has its own electronics battery and motor."

The battery-powered WAIEX is the product of the Sonex e-flight initiative. The company launched the program in 2006 to promote the development of alternative energy sources for aircraft.

"We are faced today with what I believe is a watershed 9 event," said Craig Willan.

Craig Willan is a flight engineer. He's closely monitored the development of electric powered aircraft.

"What is electric mobility 10 going to give us?  Not only on the ground but in the air?  The sky's the limit," he said. "It's a clean, renewable, highly efficient form of propulsion."

Sikorsky Engineer Jonathan Hartman agrees.

"Electric propulsion has a lot of benefits over internal combustion engines," he said. "It's quieter, it has less vibration 11, its inherently less complex which drives down costs, and it's easier to operate."

Hartman is part of a team at Sikorsky Aircraft working on Project Firefly. It's a single rotor helicopter powered by batteries made by US Hybrid 12.

"The power source for the aircraft are the two battery packs you see on either side, which are lithium ion batteries which are similar to what you find in our laptops, only custom made for us for this application," said Hartman.

Hartman says the wide swing in fuel prices made Sikorsky think about an alternative. 

"Rotor craft specifically play a critical role for both military and commercial applications," he said. "And that role could be threatened by shortages in fuel or spiraling fuel costs."

But the very thing that drives electric powered aircraft is also the biggest hurdle 13. Batteries are bulky and heavy, and for machines that need to be light. the major innovation ahead is making those batteries lighter 14 and smaller.

Hartman thinks Sikorsky has found a solution. Although Project Firefly is still grounded, Hartman expects manned flight tests to begin soon.

"This can fly, and will fly," said Jonathan Hartman. "And we're looking forward to doing so when ground tests end, which we anticipate for later this year."

The Sonex and Sikorsky projects are two examples in a growing field of innovation in electric powered flight - most in their infancy 15.

Experts say bringing this technology to commercial air travel is a dream far in the future.