The Northrop HL-10 was a NASA heavy lifting body design built to study the inverted airfoil and delta configuration. It was one of five lifting body designs flown by NASA between 1966 and 1975. The aircraft were flown at the NASA Flight Research Center (later known as Dryden Flight Research Center).
The aircraft were flown to high altitude suspended below the wing of a B-52 aircraft. Once altitude was reached the craft would be released. The HL-10 was the most successful of the five designs. It flew 37 times and attained a maximum speed of Mach 1.86 and a maximum altitude of 90,303 feet on two different flights.
The data gathered from the lifting body test flights proved valuable during the design of the Space Shuttle.
The HL-10 was famously featured during the opening scenes of the "Six Million Dollar Man". Lee Majors as Colonel Steve Austin is shown piloting the craft and other footage of the crash of a different lifting body (Northrop M2F2) is shown.