An AQM-38A preserved at White Sands Missile Range Museum.
The origins of the AQM-38 lie in the RP-70
(XKD4R-1) radio-controlled drone which Northrop developed
in 1957. A purely developmental model,
the drone was never produced in this form but did lead to the production of
its successor. In the late 1950's, Northrop's Radioplane division developed
the RP-76 a high-performance, rocket powered, radio controlled,
recoverable subscale target drone, destined to be launched from the USAF's
F-89 Scorpion. It was used for surface-to-air, and air-to-air missile firing
practice. Like the earlier Crossbow,
the RP-76 had a cigar-shaped fuselage and guidance provided by an autopilot
with RC backup, but it was much
smaller and was powered by a solid rocket engine, with an exhaust nozzle just
behind each wing. It had a unique set of flying surfaces: shoulder mounted
wings with a slight sweepback, three forward control fins underneath each side
of the nose, a peculiar downward-mounted fixed horizontal "tee" tail
located below the ventral vertical tail, and smaller dorsal fin.
The key structural
component of the RP-76 was the steel engine case housing the solid propellant
rocket motor. To this, the plastic wings,
nose section, and aft fuselage were attached. The integral flight control package,
including control vanes, was located in the nose section.
- Encyclopedia Astronautica
- Western Museum of Flight
Radioplane RP-76 / RP-78
USAF / Army designation: RP-76, AQM-38A
US Navy designation:
Powerplant: 1 x 160 N (37 lb) Aerojet 530NS35
1 x 440 N (100 lb)
Significant date: 1958
The RP-76 entered service with the US Army in 1959, usually launched from
F-89 Scorpion aircraft as a target for surface-to-air missiles. It was powered
by an Aerojet solid-fuel rocket, giving a flight at high subsonic speed for
almost 10 minutes. Controlled by an automatic system in flight, the missile
could also be guided by radio. The fuselage was fitted with a fixed horizontal
tailplane below the tail and three forward control fins. A two stage parachute
allowed it to land once the mission was completed. Radar reflectivity augmentation
equipment (i.e. to increase the radar signature)
included a Luneberg lens which provided reliable passive reflectivity at a
minimum cost as a target for the Nike-Ajax, Nike Hercules, and Hawk missiles.
The RP-76 used a Northrop RPTA-1 tracking aid system. Smoke generating and
night light kits were used for visual tracking.
The RP-76 was
powered by an Aerojet solid-propellant rocket engine with twin thrust
nozzles canted 15 degrees outboard in the horizontal plane; this produced
a thrust of 160 N (37
lb) for about 9 minutes. The drone had two
rocket exhausts at the sides of the fuselage, and could reach a speed of Mach
0.94. The RP-76 was controlled
in flight by an automatic control system with optional command control override
by radio command, and could be recovered by a two-stage parachute system.
vanes formed an integral part of the fuselage. Recovery was done with a three
foot diameter ribbon brake parachute and a second stage 24 foot diameter ring
deployed at a predetermined altitude.
Beginning in 1959, the RP-76 was used by the US Army to train surface-to-air
missile crews at US and Far East target ranges, mainly with the MIM-3 Nike-Ajax.
enough, throughout these Air Force/Army guises the
RP-76 apparently never received any designation other than its company
designation until 1963, when it was redesignated as AQM-38A.
The AQM-38A appears to have been largely made of plastics, and carried radar
It appears to have
been replaced by the Beech AQM-37, discussed later, and was phased out
in the early 1970s.
During the summer of 1960, at the White Sands Missile Range in New Mexico,
an AQM-38A climbed to a height of 72,500 feet, attaining a speed of Mach 1.03
during the flight. Later, a new high performance version, designated RP-76E,
attained a speed in excess of Mach 2 at an altitude of 80,000 feet. The US
Navy also produced a modified version, the RP-78, which
had a higher thrust rocket motor allowing
supersonic speeds of up to Mach 1.25. This was used for air-to-air missile
training of US Navy all-weather interceptor fighter pilots at the Pacific Missile
Range, Point Magu, California. Interestingly, the Navy's
RP-78 was apparently never designated as KD4R-1 (or -2)
but retained its company designator, although it was clearly a production
development of the XKD4R-1.
The RP-78 was redesignated as AQM-38B in the 1963 reformed
tri-service system. Since mid-1959, over 2,000 of the AQM-38A/B targets were
ordered by the US Armed
Population: over 2000
Specs & performance:
Length: 2.95 m (9 ft 8 in)
Wingspan: 1.52 m (5 ft)
Height: 0.46 m (1 ft 6.2 in)
Diameter: 30 cm (12 in)
Empty Weight: 197 lb.
Launch Weight: 136 kg (301 lb)
Speed (AQM-38A): Mach 0.94
Mach 1.25 (1,450
Ceiling (AQM-38A): 18,300 m (60,000 ft)
Ceiling (AQM-38A): 24,000 m (78,700 ft) (some give 24,400
Endurance: 23 min. (powered: 9 min.)
Range (AQM-38B): 70 km (44 miles)
Guidance: Command Link
Liftoff Thrust: 45 kgf
Maximum range: 65 km
Acquisition Range in S-Band: 110,000 yds.
Tracking Radar Range in X-Band: 73,000 yds