#hl-10

View of the three North American X-15s, Northrop HL-10, M2-F1, Northrop M2-F2 Lifting Body, McDonnell F-4 Phantom II, Douglas F5D Skyraye and a Douglas DC-3 in the main NASA hanger at the Dryden Flight Research Center in Edwards Air Force Base, California.

Date: 1966

"The HL-10 is shown next to the X-15A-2 in 1966. Both aircraft later went on to set records. On October 3, 1967, the X-15A-2 reached a speed of Mach 6.7, which was the highest speed achieved by a piloted aircraft until the Space Shuttles far exceeded that speed in 1981 and afterwards."

Date: May 27, 1966

"NASA research pilot Bill Dana takes a moment to watch NASA's NB-52B cruise overhead after a research flight in the HL-10. On the left, John Reeves can be seen at the cockpit of the lifting body."

Date: May 20, 1969

"Wingless Flight" by Mark Karvon: link

"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.