Given the company designation NA-273, the Redhead/Roadrunner drone program produced a small aircraft of largely conventional design, with small delta wings and a downswept tailplane; the vertical stabilizer doubled as a pylon for the aircraft's ramjet engine. A solid-propellant rocket provided thrust until the ramjet reached operating speed; launch was from the same launcher as that used by the MGR-3 Little John battlefield rocket.[1] Two minor variants of the drone were produced; 'Redhead' was optimized for high-altitude flight, at heights of up to 60,000 feet (18,000 m), while 'Roadrunner' was a variant for low-altitude operation as low as 300 feet (91 m) above the ground, and both could reach speeds of between Mach 0.9 and Mach 2. An autopilot, set to maintain a preset altitude, provided control of the drone; radio command guidance from a ground control station could override the autopilot. At the end of a flight, if the target drone had not been shot down, recovery could be either on command from the ground station, or automatic in case of fuel exhaustion or loss of control; a retrorocket would decelerate the drone to allow for deployment of a recovery parachute.[2]
First flight of the NA-273 took place in 1961; in 1963, the designation MQM-42A was applied to both variants. The MQM-42 was used primarily to provide training in tracking and engaging targets for the MIM-23 Hawk surface-to-air missile;[3] it remained in service with the United States Army through the mid-1970s.[2]
Haggerty, James J. (1968). 1968 United States Aircraft, Missiles and Spacecraft. Washington D.C.: National Aerospace Education Council. ASINB005PPVSQK.
