You've probably heard of very light jets-the diminutive personal aircraft commonly known as VLJs-but how about NAJs (No Airplane Jets)? Swiss pilot Yves Rossy recently flew across the English Channel with what was basically a jet-propelled hang glider strapped to his back. "Flying is a passion," said the 49-year-old Rossy, a former military fighter pilot who now works as a captain for Swiss Airlines. "I tried lots of sports, such as sky surfing. But I always wanted to fly like a bird."

Rossy has now done just that more than 30 times with his homemade carbon-fiber wing, which is powered by four engines originally intended for model airplanes. Located just inches from the hot exhaust during flight, he must wear a protective suit. The engines don't have enough thrust or fuel to carry a person aloft from the ground, so Rossy's flights begin with him jumping from an aircraft. Since the wing lacks a tail and control surfaces, he steers by tilting his head or turning his body.

For the Channel flight on September 26, Rossy planned to follow the path of aviation pioneer Louis Bleriot, who 99 years ago became the first pilot to fly across the Channel. After jumping from a single-engine airplane 8,000 feet above Calais on the French coast, Rossy completed the nearly 22-mile flight in 13 minutes at an average speed of 124 mph and parachuted to the ground near Dover.