Unique Flying Machines: Lockheed Martin P-791: This month, we're celebrating the P-791, a hybrid airship that combines aerostatic and aerodynamic lift.It has a tri-hull-shaped exterior and disk-shaped cushions underneath for landing.The P-791 was intended to serve as a long endurance, multi-intelligence vehicle (LEMV) for the U.S. Amry but ultimately was not selected.Lockheed Martin modified it to transport civilian cargo and named it "Sky Tug", with a lift capacity of 18,000 kilograms (20 tons).The airship's first flight was January 31, 2006.
