The FAA strictly regulates who, where, when and why unmanned air craft will be flown.

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Washington has been beefing up its joint exercises with South Korea and has added flights of its nuclear capable air craft near the Korean Peninsula, first B-52 bombers and now the B-2 stealth planes.

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And part of it will be met with huge landing craft that ride on air cushions.

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The craft, partially owned by Virgin group overlord Sir Richard Branson and the Abu Dhabi-based investment group PJC, took off earlier today from its berth at Mojave Air and Space Port in California, where carrier-craft WhiteKnightTwo ferried it to a 47, 000 ft altitude after which its own rockets kicked in for a supersonic flight.

ENGADGET

The craft, partially owned by Virgin group overload Sir Richard Branson and the Abu Dhabi-based investment group PJC, took off earlier today from its berth at Mojave Air and Space Port in California, where carrier-craft WhiteKnightTwo ferried it to a 47, 000 ft altitude after which its own rockets kicked in for a supersonic flight.

ENGADGET

Washington could rely on ship-to-air and air-to-air missiles, but they would be less effective against low-flying craft.

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The pilot must then change the pitch of his craft to let it enter a mode called autorotation, in which the rush of air as it descends keeps the blades whirling, thus providing lift that slows the fall.

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The Air Accidents Investigation Branch (AAIB) found there was a rotor blade fault that caused them to strike the craft and separate.

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