PGM-19 Jupiter

Development history

The Jupiter traces its origins to the PGM-11 Redstone missile. While the Redstone was entering service, Wernher von Braun's Army Ballistic Missile Agency (ABMA) team at Redstone Arsenal considered an upgraded version using the LR89 engine being developed by Rocketdyne for the Air Force's Atlas missile. Adding a second stage would allow the new design to reach 1000 nmi. As Rocketdyne improved the LR89, the Army requested a similar design with 135,000 lbf of thrust in 1954.

Meanwhile, nuclear warhead weights were falling rapidly, and combining this engine with a 2000 lb warhead allowed a single-stage missile with a range of 1500–1700 miles. This engine was upgraded to 150,000 lbf, known to the Army as the NAA-150-200 and to Rocketdyne as the S-3. The US Navy, seeking to join the nuclear club, had focused on cruise missiles. Lower-ranking Navy officials became interested when the Army and Air Force developed long-range missiles, and the Navy liaison to the Killian Committee championed the concept.

In September 1955, the Committee released a report calling for a sea-based missile system. Admiral Arleigh Burke, who replaced Carney in August 1955, was convinced the Navy needed missiles and approached the Army; the proposed Jupiter fit the Navy's range goals.

Testing history

Rocketdyne tested the first S-3 engine at their Santa Susana, California facilities in November 1955. A mock-up was delivered to ABMA in January 1956, followed by prototype engines in July 1956. Testing began in September 1956 at ABMA's Power Plant Test Stand, revealing unstable combustion that caused four engine failures by November. The engine was temporarily derated to 135,000 lbf and successfully tested at that level in January 1957.

Continued development produced sub-versions, culminating in the S-3D model achieving 150,000 lbf. The 135,000 lb engine had conical thrust chambers; the 150,000 lb model used bell-shaped chambers. Unlike Thor and Atlas, Jupiter gimbaled the turbine exhaust for roll control; early test models had two small gas jets powered by turbine exhaust, with the gimbaled exhaust pipe introduced in late 1958. In 1954, Test Laboratory director Karl Heimburg began building the Static Test Stand for Redstone testing; it was repurposed for Jupiter and completed in January 1957.

A Jupiter was installed and fired for the first time on 12 February 1957, nearly ending in disaster when a small explosion occurred in the LOX pump. The foreman, Paul Kennedy, saved the day by connecting a pressure line to drain oxygen buildup. The problem was traced to lubricant that ignited in contact with LOX; a new lubricant and test stand changes were introduced.

Operational deployment

In April 1958, the U.S. Department of Defense tentatively planned to deploy the first three Jupiter squadrons (45 missiles) in France, but in June 1958 French President Charles de Gaulle refused to accept them. The U.S. then explored deploying the missiles in Italy and Turkey. The Air Force was already implementing plans to base four squadrons (60 missiles) of PGM-17 Thor IRBMs in Britain under Project Emily. In 1958, the USAF activated the 864th Strategic Missile Squadron at ABMA, and later the 865th and 866th squadrons.

In April 1959, the secretary of the Air Force ordered deployment of two Jupiter squadrons to Italy, totaling 30 missiles at 10 sites from 1961 to 1963, operated by Italian Air Force crews with USAF personnel controlling warhead arming. The first flight of three Jupiters was turned over to the Turkish Air Force in late October 1962, but USAF retained control of nuclear warhead arming.

Description

Jupiter squadrons consisted of 15 missiles and about 500 military personnel, organized into five flights of three missiles each. Flights were located about 30 miles apart, with triple launcher emplacements separated by several hundred miles. Each emplacement's ground equipment was housed in about 20 vehicles, including generator trucks, a power distribution truck, theodolites, a hydraulic and pneumatic truck, and a liquid oxygen truck. A trailer carried 6000 gallons of fuel, and three LOX trailers each carried 4000 gallons.

Missiles arrived on large trailers; the crew attached a hinged launch pedestal and winched the missile upright. Fuel and oxidizer lines were connected, and the bottom third of the missile was encased in a flower petal shelter of wedge-shaped metal panels for servicing in all weather. The launch control officer and two crewmen in a mobile launch control trailer could then launch. Each squadron had a receipt, inspection and maintenance (RIM) area that inspected new missiles and provided field maintenance, housing 25 tons of LOX and nitrogen generating plants.

Did You Know?

• The Saturn I and Saturn IB first stages used tooling from Jupiter and Redstone production, with a central Jupiter-diameter tank and eight Redstone-diameter tanks clustered around it.
• The Juno II, a four-stage space launch vehicle derived from the Jupiter, was used for 10 satellite launches, six of which failed; it launched Pioneer 3, Pioneer 4, Explorer 7, Explorer 8, and Explorer 11.