RQ-4 Global Hawk Crash At China Lake

More than half of the seven prototypes of the unmanned Global Hawk - a central plank of the new $50 billion defence spending plan - have been damaged or destroyed through technical failure or misadventure.

The Global Hawk disasters include one lost after a bolt was installed backwards during servicing. A second plane was lost after accidentally picking up a self-destruct signal that was designed to bring down a nearby missile.

A third was lost through engine failure, and a fourth was damaged after crashing when its US military handler made a typing error on a computer control pad.