Jupiter IRBM

SM-78/PGM-19 Jupiter
Jupiter missile emplacement showing ground support equipment. The bottom third of the missile is encased in a "flower petal shelter" of wedge-shaped metal panels allowing crews to service the missile in all weather conditions.
Type	Medium-range ballistic missile (MRBM)
Place of origin	United States
Service history
Used by	United States Air Force Italian Air Force Turkish Air Force
Production history
Designed	1954
Manufacturer	Chrysler
Produced	1956–1961
No. built	≈100 (45 deployed)
Variants	Juno II
Specifications
Weight	49,800 kg (110,000 lb)
Length	18.3 m (60 ft)
Diameter	2.67 m (8 ft 9 in)
Propellant	kerosene and liquid oxygen
Operational range	1,500 mi (2,400 km)
Flight ceiling	610 km (380 mi)

The PGM-19 Jupiter was the first nuclear tipped, medium-range ballistic missile (MRBM) of the United States Air Force (USAF). It was a liquid-propellant rocket using RP-1 fuel and LOX oxidizer, with a single Rocketdyne LR70-NA (model S-3D) rocket engine producing 667 kN of thrust. It was armed with the 1.1 megaton W49 nuclear warhead. The prime contractor was the Chrysler Corporation.

The Jupiter was originally designed by the US Army, which was looking for a highly accurate missile designed to strike high-value targets like bridges, railway yards, troop concentrations and the like. The Navy also expressed an interest in the design as an SLBM, but left the collaboration to work on their Polaris. Jupiter retained the short, squat shape intended to fit in naval submarines.

The U.S. Army set accuracy goals so high that some expressed skepticism they could be met, but the Redstone team successfully designed a system with a circular error probable (CEP) of 0.5 miles (0.80 km), substantially more accurate than similar designs like the US Air Force's Thor. A presidential report suggested this made it the most valuable missile then being developed. This led to continual inter-service fighting between the Army and Air Force, and ultimately to Charles Erwin Wilson's decision to give the Jupiter missiles to the U.S. Air Force.

The Air Force was never greatly interested in supporting Jupiter; they saw no need for its accuracy in their battle plans and had their own Thor with longer range. Production went ahead and the nuclear tipped missiles were deployed in both Italy and Turkey in 1961 due to NATO's Cold War deterrence against the Soviet Union. All were then later removed by the United States as part of a secret agreement (The Secret Deal) with the Soviet Union during the Cuban Missile Crisis. They were considered to be outdated. It was also used as the basis for a satellite launcher known as Juno II, but had a short and unsuccessful career in this role. It is unclear as to what happened to the missiles in Italy, but they too were removed at some point.