MGM-18 Lacrosse

M4 (MGM-18) Lacrosse
MGM-18 Lacrosse on an XM-398 Launcher
Type	Tactical ballistic missile
Place of origin	United States
Service history
In service	1959–1964
Used by	United States Army
Wars	Cold War
Production history
Designer	Johns Hopkins University, Cornell Aeronautical Laboratory
Designed	1947–1956
Manufacturer	The Glenn L. Martin Company
Produced	1959–1964
No. built	Nearly 1200
Specifications
Weight	2,300 pounds (1,000 kg)
Length	19 feet 2.4 inches (5.852 m)
Diameter	20.5 inches (520 mm)
Maximum firing range	12 miles (19 km)
Warhead	Explosive or Nuclear
Warhead weight	540 pounds (240 kg)
Blast yield	Explosive or 1.5–10 kt Nuclear using the W40 nuclear warhead
Wingspan	9 feet (2.7 m)
Propellant	Thiokol XM10 or XM10E1 solid-fuel rocket
Speed	mach 0.8
Guidance system	Radio Command guidance
Launch platform	XM-398 transporter/launcher truck

The MGM-18 Lacrosse was a short-ranged tactical ballistic weapon intended for close support of ground troops. Its first flight test was in 1954 and was deployed by the United States Army beginning in 1959, despite being still in the development stage. The program's many technical hurdles proved too difficult to overcome and the missile was withdrawn from field service by 1964.

The Lacrosse project began with a United States Marine Corps requirement for a short-range guided missile to supplement conventional field artillery. The navy's Bureau of Ordnance issued contracts to both the Johns Hopkins University Applied Physics Laboratory and the Cornell Aeronautical Laboratory in September 1947, for the study of design aspects pertaining to this mission.

The missile system was named the Lacrosse because it employed a forward observation station which had a direct view of the target. The forward observation station was mounted on a jeep and after the missile was launched control was passed to the forward station for final guidance to the target. Hence the name Lacrosse which is how the game of lacrosse is played with the ball being passed to players closer to the goal.

In 1950, the project was transferred from the navy to the army's Ordnance Corps and Redstone Arsenal, pursuant to a policy giving the Department of the Army responsibility over all land-based short ranged weapons. Cornell and Johns Hopkins continued with the project, with the former having primary responsibility for guidance systems design.

In 1955, the Glenn L. Martin Company was awarded contracts to participate in research and development and production. Martin would take over much responsibility for the project, as Cornell moved to work on expanding the missile's capabilities beyond the original requirements (particularly in the area of airborne control, funding for which was discontinued in 1959).

Early testing began in 1954 and production prototypes were available the next year. The difficulties encountered by the project are illustrated by the protracted design and testing periods, with the missile not entering into service until July 1959. Problems included reliability concerns and difficulties with guidance, particularly susceptibility to ECM jamming of the guidance signals.