SM-62 Snark
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The Northrop SM-62 Snark was a specialised intercontinental missile with a nuclear warhead briefly operated by the US Strategic Air Command from 1958 until 1961.
Basically an unmanned aircraft, the jet engined 20.5 m long device had a top speed of 650 mph (1,046 km/h) and a maximum range of 5,500 nautical miles (10,200 km). The complex stellar navigation based guidance system gave a claimed CEP of 8,000 ft (2.4 km).
The Snark was an air-breathing design, launched from a light platform by two rocket booster engines. It would switch to an internal jet engine for the remainder of its flight. The jet was a Pratt and Whitney J57, the first 10,000 lbf (44 kN) thrust design, also used in the early B-52 and the F-100. Lacking a horizontal tail surface and using elevons as the main control surfaces the missile flew an unusual nose high aspect during level flight. During the final phase of flight the nuclear warhead would detach and follow a ballistic trajectory to the target. The missile itself would become unflyable and crash as soon as the warhead detached.
It was developed to offer a nuclear threat to the Soviet Union at a time when ICBMs were still in development. Work on the project had begun in 1946. Initially there were two missiles - a subsonic design (the MX775A Snark) and a supersonic design (the MX775B Boojum). Budget reductions threatened the project in its first year but the personal intervention of Jack Northrop with Carl Spaatz saved the project. Despite this funding was low and the program was dogged by requirement changes. The expected due date of 1953 passed with the design still in testing and SAC was becoming less enthusiastic. In 1955 Eisenhower ordered top priority to the ICBM and associated missile programs.
Despite considerable difficulties with the missile and military reservations work continued. In 1957 tests the missile had an average CEP of 17 nautical miles (31.5 km) and the most accurate test of 1958 fell 4 nautical miles (7.4 km) short. The design was also notoriously unreliable with the majority of test missiles suffering mechanical failure thousands of miles before reaching the target area. The reduced operating altitude, from 150,000 to 55,000 ft (46 to 17 km), and the inability of the missile to undertake evasive manoeuvres were also cited against it.
One of the more advanced features of the Snark was its ability to fly missions of up to 11 hours and return for a landing. If the Snark did not detach its warhead, the missile itself could be flown repeatedly. Lacking landing gear, it was necessary for the Snark to skid to a landing on a flat, level surface.
In January 1958 the Strategic Air Command began accepting delivery of operational missiles to Patrick AFB in Florida for training and in 1959 the 702nd Strategic Missile Wing was formed. Multiple launch failures led to the Atlantic Ocean off of Cape Canaveral being described as "Snark infested waters."
On 27 May 1959, Presque Isle AFB in Maine, the only Snark base, received its first Snark Missile. Ten months later, on March 18, 1960, a Snark missile officially went on alert status.
The 702nd was not declared fully operational until February 1961. In March, 1961 President Kennedy declared the Snark to be "obsolete and of marginal military value" and on 25 June 1961 the 702nd was inactivated.[1]
The missile name is from the Lewis Carroll poem The Hunting of the Snark.
[edit] Specifications
[edit] General characteristics
- Length: 67 ft 2 in (20.47 m)
- Wingspan: 42 ft 3 in (12.88 m)
- Wing area: ft² ( m²)
- Weight: 48,147 lb (21,839 kg) without booster, 60,000 (27,200 kg) with booster
- Powerplant: 1× Pratt & Whitney J57 jet engine; 10,500 lbf (46.7 kN) thrust. 2 Aerojet-General solid-propellant rocket boosters; 130,000 lbf (580 kN) thrust
[edit] Performance
- Maximum speed: 565 knots (1,050 km/h)
- Combat range: 5,497 nmiles (10,180 km)
- Service ceiling: 50,250 ft (15,320 m)
- Rate of climb: ft/min ( m/min)
- Wing loading: lb/ft² ( kg/m²)
- Thrust/weight: 0.218:1
[edit] Armament
- Nuclear warhead
[edit] Operators
- United States: The United States Air Force was the only operator of the Snark.