The US Army conceived a requirement to equip its airborne units with nuclear weapons in 1953. Development of a nuclear-tipped unguided rocket started in June 1955, with first launch a year later. Firings of production versions began in December 1958, with first deployment in January 1961. The rocket was retired in August 1969, considered redundant to nuclear artillery. Little John was an air-transportable, unguided rocket powered by an XM26 solid-fuel rocket motor, and armed with a nuclear 1-10 kT W-45 nuclear fission or conventional warhead. The missile was delivered fully assembled to the firing units, either by helicopter, or driven on its M34 towed launcher.
Development Cost $: 51.900 million. Recurring Price $: 0.014 million in 1960 dollars. Flyaway Unit Cost $: 0.008 million in 1960 dollars. Standard warhead: 110 kg (240 lb). Maximum range: 18 km (11 mi). Number Standard Warheads: 1. Standard warhead: W45. Warhead yield: 15 KT. Boost Propulsion: Solid rocket. Maximum speed: 2,600 kph (1,600 mph). Initial Operational Capability: 1960. Total Number Built: 2404. Total Development Built: 61. Total Production Built: 2343.
Historical Essay © Andreas Parsch
Emerson Electric M47-M51-MGR-3 Little John
The Little John was the smallest nuclear-capable rocket the U.S. Army ever deployed. Studies to develop a lightweight rocket based on the M31-MGR-1 Honest John to give airborne Army units a nuclear capability began in 1953 under the name Honest John Junior. After preliminary studies by Douglas during 1954, the development program - renamed as Little John - was officially started at Redstone Arsenal in June 1955. In June 1956, the first launch of the XM47 Little John occurred. The XM47 was only an interim rocket, essentially a rocket test vehicle, and was used for training and testing purposes only.
Development of the final tactical Little John, then known as XM51, began in 1956, and test firings were conducted between December 1958 and October 1959. Production of the XM51 rocket began in late 1959, and the first rockets were deployed by airborne battalions in January 1961. In September 1961 the XM51 Little John was reclassified as M51.
The M51 Little John was an air-transportable, unguided artillery rocket powered by an XM26 solid-fuel rocket motor, and armed with a nuclear or conventional warhead. The M51 was delivered fully assembled to the firing units, either by helicopter, or already mounted on its M34 towed launcher. Once the launch site was reached, the Little John was ready for aiming and firing.
In 1963, when production was already completed (all by Emerson Electric), the M51 was redesignated as MGR-3A. Little John production and deployment was limited, because it was designed mainly for airborne operations, and there were only two airborne Army units at the time. In August 1969, the MGR-3A was withdrawn from service. There was no official reason for this early retirement, but it's possible that the rocket was considered redundant after the M454 155mm nuclear projectile had been fielded in 1964.Specifications
Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!
Data for MGR-3A:
|Length||4.41 m (14 ft 5.7 in)|
|Finspan||0.60 m (1 ft 11.75 in)|
|Diameter||0.32 m (12.5 in)|
|Weight||353 kg (779 lb)|
|Range||18.2 km (11.3 miles)|
|Propulsion||Hercules XM26 solid-fueled rocket motor|
|Warhead||W-45 nuclear fission (1-10 kT); or conventional HE|
 James N. Gibson: "Nuclear Weapons of the United States", Schiffer Publishing Ltd, 1996
 Bill Gunston: "The Illustrated Encyclopedia of Rockets and Missiles", Salamander Books Ltd, 1979
 Redstone Arsenal Historical Information Website
AKA: M47 + M32, M51 + M34, M15 motors; MGR-3; Little John.
Status: Retired 1969.
Gross mass: 354 kg (780 lb).
Payload: 110 kg (240 lb).
Height: 4.42 m (14.50 ft).
Diameter: 0.30 m (0.98 ft).
Span: 0.58 m (1.90 ft).
Thrust: 240.20 kN (53,999 lbf).