The NASA M2-F1 is a lightweight, unpowered prototype aircraft, developed to flight-test the wingless lifting body concept.

Ernie Lowder, a NASA craftsman who had worked on Howard Hughes's H-4 Hercules ("Spruce Goose"), was assigned to help Briegleb.

The wingless, lifting-body aircraft design was initially conceived as a means of landing a spacecraft horizontally after atmospheric reentry.

Rather than using a ballistic reentry trajectory like a Command Module, very limited in maneuvering range, a lifting-body vehicle had a landing footprint of the size of California.

The first flight tests of the M2-F1 were at Rogers Dry Lake, at the end of a tow rope attached to a 1963 Pontiac Catalina convertible.

It was found that the car used to tow the aircraft was not powerful enough to lift the M2-F1 entirely off the ground, so the FRC arranged to have the tow car hot-rodded by Bill Straub: the modifications tuned the engine for increased power, added a rollbar, and turned the front passenger seat to face aft so the passenger could observe the aircraft.

[2] Speeds on tow inched up to 110 miles per hour (180 km/h), which allowed Thompson to climb to about 20 feet (6.1 m), then glide for about 20 seconds after releasing the line.

The M2-F1 had recently been equipped with an ejection seat and small rockets – referred to by the test team as "instant L/D"[2] – in the tail to extend the landing flare for about 5 seconds if needed, and Thompson prepared for the flight with a few more tows behind the Pontiac.

Forward visibility in the M2-F1 was very limited on tow, requiring Thompson to fly about 20 feet (6.1 m) higher than the C-47, so he could see the plane through the nose window.

It also demonstrated a procurement and management concept for prototype flight research vehicles that produced rapid results at very low cost (approximately US$50,000, excluding salaries of government employees assigned to the project).