Virgin Galactic just keeps on ticking off the milestones on its way to  becoming the first commercial company to take tourists on high-altitude  flights to suborbital space and return them safely through the  atmosphere to Earth. In the video below, we actually get to see Virgin’s  SpaceShipTwo (aka VSS Enterprise) making its first “feathered” flight. “Feathering,” as it is known, is probably the biggest innovation  integrated into SpaceShipTwo’s design. In the feathered position, the  entire tail section of the plane rotates upward about 65 degrees,  creating a different aerodynamic shape that is highly stable yet creates  tremendous drag to slow the aircraft down during re-entry. Though that  drag is pretty significant, the light weight of the aircraft keeps the  skin temperature from rising too high, circumventing the need for heat  shields and other thermal protection. 
Moreover, when feathered correctly the aircraft is so stable that the  pilot can more or less take his hands off the sticks and let the  aircraft work its way through the atmosphere naturally, based purely on  its aerodynamic shape. That’s a huge safety feature, as the pilot  doesn’t have to maintain a specific degree of entry or rely on a  sophisticated fly-by-wire computer.
The test shown below took place May 4 and did not actually include a  trip to space. But this first feathering test, which began when  SpaceShipTwo was dropped from the carrier aircraft WhiteKnightTwo at  51,500 feet, proves that Burt Rutan’s feathering design actually works  as well in the air as it did on paper. Where you see the aircraft  feather, keep in mind that it is basically falling straight down at  15,500 feet per minute, a rate that is slowed significantly by the  aerodynamic drag generated by the feathering configuration.
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