Lockheed P-791. A blimp, not really. Can spend up to 3 weeks at an altitude of 20,000 feet (6,100 m) with a 2,500 pound (1,134 kg) payload of surveilance equipment by the middle of 2011. The LEMV is a hybrid airship - it's heavier than air, 80% of its lift coming from buoyancy and 20% from aerodynamics. Propulsion comes from six thrusters - three per side - powered by individual turbo-diesels for take-off and climb, and electrically from a central turbo-generator for loiter. And it's non-rigid, structural stability results from the three-lobe envelope design. The airship is also optionally piloted - flown manned for self-deployment and unmanned for persistent ISR missions. An air cushion landing system allows the airship to be maneuvered for taxiing and take off, and sucks the vehicle down on to the ground - or sea surface - for landing, loading and unloading. Hanging under the envelope, behind the sometimes-occupied cockpit, is a payload bay 40ft long, 15ft wide and 6-8ft tall - more than enough room to mount either a ground moving-target indication radar or multi-camera wide-area motion imagery sensor, plus a signals-intelligence payload and multiple EO/IR sensors.