Scientists half-jokingly call it the "ignorosphere" -- a region about 50-100 kilometers above the Earth that's too high for airplanes, but too low for satellites. "It earned its name because even though the area is valuable to researchers, there has been no easy way to get to it," said Alan Stern, planetary scientist at the Southwest Research Institute. But, Stern says, suborbital flights, like those made by Virgin Galactic's SpaceShipTwo, go right to the heart of this region, which includes the layer of the Earth's atmosphere that lies above the stratosphere and below the thermosphere.
Photographed from an ultra-light plane last December, these whooping cranes are being taught to fly south for the winter. Almost completely wiped out by 1940, there are now 536 known captive and wild whooping cranes in North America. But those raised in captivity will not migrate to warmer climes automatically -- they have to learn the skill.
The builder says his goal was a noiseless plane that would fly as smoothly as a magic carpet.
John B. Carnett
In August, at the Experimental Aircraft Association (EAA) AirVenture show in Oshkosh, Wisconsin, Randall Fishman's ElectraFlyer-C made a virtually silent pass over the audience at a mere 200 feet. What they were seeing (but not hearing) might be the world's first fully electric-powered airplane—representing, said one EAA official, "a groundbreaking technology that would be aviation's first true alternative to a fossil-fuel engine."
Last year, U.S. airlines canceled 21,000 flights. Or rather, a small cadre of guys canceled 21,000 flights. Every gate agent reports up the ladder at a given airline to a set of command-center managers. We spoke with a few of the people who make the big decisions to learn what factors influence whether they cancel a flight.