SM-62 Snark

Northrop SM-62 Snark

Type	Surface-to-surface cruise missile
Place of origin	United States
Service history
In service	1959–61
Used by	United States Air Force
Production history
Manufacturer	Northrop Corporation
Produced	1958–61
Specifications
Weight	48,150 pounds (21,850 kilogram) without boosters; 60,000 pounds (27,200 kg) with boosters
Length	67 feet, two inches (20.5 meters)
Warhead	W39 thermonuclear warhead (explosive yield: 3.8 megatons)

Engine	one Pratt & Whitney J57 jet engine; and two Aerojet solid-propellant rocket boosters J57 turbojet: 10,500 pounds (46.7 kilonewtons) of thrust; booster rockets: 130,000 pounds (580 kilonewtons) of thrust
Wingspan	42 feet, three inches (12.9 meters)
Operational range	5,500 nautical miles (10,200 kilometers)
Flight ceiling	50,250 feet (15,300 meters)
Speed	565 nautical mile/hour (1,050 kilometer/hour)
Guidance system	astro-inertial guidance with CEP of about 8,000 feet (2.4 kilometers).
Launch platform	mobile launcher

The Northrop SM-62 Snark was an early-model intercontinental range ground-launched cruise missile that could carry a W39 thermonuclear warhead. The Snark was deployed by the United States Air Force's Strategic Air Command from 1958 through 1961. It represented an important step in weapons technology during the Cold War.^[1] The Snark took its name from the author Lewis Carroll's character the "snark".^[2]

The Snark missile was developed to present a nuclear deterrent to the Soviet Union and other potential enemies at a time when Intercontinental ballistic missiles (ICBMs) were still in development. The Snark was the only surface-to-surface cruise missile with such a long range that was ever deployed by the U.S. Air Force. Following the deployment of ICBMs, the Snark was rendered obsolete, and it was removed from deployment in 1961.

Design and development

Display at the National Museum of the United States Air Force

Work on the project began in 1946. Initially there were two missiles designed—a subsonic design (the MX775A Snark) and a supersonic design (the MX775B Boojum).(From the same poem: "The snark was a boojum, you see."^[3]) Budget reductions threatened the project in its first year, but the intervention of Air Force General Carl Spaatz and the industrialist Jack Northrop saved the project. Despite this, its funding by Congress was low, and this program was dogged by changes in specifications. The earliest planned due date in 1953 passed with the design still in development, and the Strategic Air Command was gradually becoming less supportive of it. In 1955, President Dwight D. Eisenhower ordered that top priority be assigned to ICBMs and their associated guided missile programs.

Despite considerable difficulties with the development of the Snark, and reservations from the Department of Defense towards it, the engineering work continued.^[4]

In 1957, tests of the Snark showed an estimated circular error probable (CEP) of just 17 nautical miles (31.5 kilometers). By 1958, the celestial navigation system used by the Snark allowed its most accurate test, which appeared to fall four nautical miles (7.4 km) short of the target. However, this apparent failure was at least partially caused by the British Navigation Charts used to determine the position of Ascension Island being based on position determinations less accurate than those used by the Snark. The missile landed where Ascension Island would be found if more accurate navigation methods had been used when developing the chart.^[5] However, even with the decreased CEP, the design was notoriously unreliable, with the majority of tests suffering mechanical failure thousands of miles before reaching the target. Other factors, such as the reduction in operating altitude from 150,000 to 55,000 feet (46,000 to 17,000 meters), and the inability of the Snark to detect countermeasures and perform evasive maneuvers also made it a questionable strategic deterrent.

Technical description

Northrop SM-62 Snark, Hill Aerospace Museum.

The jet propelled 20.5 meter-long Snark missile had a top speed of about 650 mph (1,046 km/h) and a maximum range of about 5,500 nautical miles (10,200 kilometers). Its complicated celestial navigation system gave it a claimed CEP of about 8,000 feet (2.4 kilometers).

The Snark was an air-breathing missile, intended to be launched from a truck-mounted platform by two solid-fueled rocket booster engines. The Snark next switched to an internal turbojet engine for the rest of its flight. The engine was a Pratt and Whitney J57, which was the first jet engine featuring a thrust of 10,000 pounds (44 kilonewtons) or more. Since the Snark lacked a horizontal tail surface, it used elevons as its primary flight control surfaces, and it flew with an unusual nose-high angle during level flight. During the final phase of its flight, its nuclear warhead would have separated from its fuselage and then followed a ballistic trajectory towards its target. Due to the abrupt shift in its center of gravity caused by separation, the fuselage would have performed an abrupt pitch-up maneuver in order to avoid a collision with the warhead.

A photo sequence showing the warhead's separation sequence

One unusual capability of the Snark missile was its ability to fly away from its launch point for up to 11 hours, and then return for a landing. If its warhead did not detach from its body, then the Snark could be flown repeatedly. Lacking any landing gear, it would have been necessary for the Snark to skid to a stop on a flat, level surface. A runway at the Cape Canaveral Air Force Station is still known as the "Skid Strip".

Operational history

In January 1958, the Strategic Air Command began accepting delivery of Snark missiles at Patrick Air Force Base for training, and in 1959, the 702d Strategic Missile Wing was formed. Multiple launch failures led to the Atlantic Ocean off Cape Canaveral's being described as "Snark infested waters."

On 27 May 1959, Presque Isle Air Force Base, Maine, the only Snark missile base, received its first missile. Ten months later, on 18 March 1960, a Snark missile went on alert status. A total of 30 Snarks are known to have been deployed.^[6]

The 702nd Wing was not declared to be fully operational until February 1961. In March 1961, President John F. Kennedy declared the Snark to be "obsolete and of marginal military value", and on 25 June 1961, the 702nd Wing was inactivated.^[7]

Many in the U.S. Military were surprised the Snark, due to its dubious guidance system, was ever operational. In flight tests many were lost. A missile launched in 1956 went so far off course that it landed in North-Eastern Brazil,^[8] where it was found in 1983.^[9] Many of those connected with the program commented in jest "That the Caribbean was full of 'Snark infested waters'."^[10]

Aerial photo showing the Snark's nose-up attitude in flight

Survivors

Air Force Space & Missile Museum, Cape Canaveral Air Force Station, Florida. This pristine artifact is in sequestered storage in Hangar R on Cape Canaveral AFS and cannot be viewed by the general public.
National Museum of the United States Air Force, Wright-Patterson Air Force Base, Dayton, Ohio
Strategic Air and Space Museum, Ashland, Nebraska
Hill Air Force Base, Ogden, Utah
National Museum of Nuclear Science & History, adjacent to Kirtland AFB, Albuquerque, New Mexico

References

Notes

↑ Northrop SM-62 Snark. National Museum of the United States Air Force. May 29, 2015.
↑ Carroll and Gardner 1982, p. 97.
↑ Carroll and Gardner 1982, pp. 14, 53.
↑ "Video: Arctic Sentinels. Building Rushed on Radar Defense, 1956/04/09." Universal Newsreel, 1956. Retrieved: 20 February 2012.
↑ "Personal interview with George F. Douglas, Chief Project Engineer, c. 1967"
↑ Gibson 1996, p. 151.
↑ "U.S. Air Force Fact Sheet: Development of the 45SW Eastern Rqnge." United States Air Force. Retrieved: 12 April 2012.
↑ "Snark ignores Air Force 'orders'." Pittsburgh Post-Gazette, 8 December 1956. Retrieved: 6 January 2013.
↑ "Long-lost missile found." The Leader-Post, 15 January 1983. Retrieved: 6 January 2013.
↑ Zaloga 1993, p. 193.

Bibliography

Carroll, Lewis and Martin Gardner. Lewis Carroll's The Hunting of the Snark: The Annotated Snark. London: William Kaufmann, 1982. ISBN 978-0-913232-36-1.
Gibson, James N. Nuclear Weapons of the United States: An Illustrated History. Atglen, Pennsylvania: Schiffer Publishing Ltd., 1996. ISBN 0-7643-0063-6.
Zaloga, Steven J. "Chapter 5." Target America: The Soviet Union and the Strategic Arms Race, 1945–1964. New York: Presido Press, 1993. ISBN O-89141-400-2.

External links

Wikimedia Commons has media related to Northrop SM-62.

Northrop aircraft

Manufacturer
designations

'Greek' series	Alpha Beta Gamma Delta

'N' series	Note: Northrop company designations include a wide variety of technologies. Only aircraft, aero engines, and missiles are linked here. N-1 N-2 N-3 N-4 N-5 N-6 N-7 N-8 N-9 N-10 N-12 N-14 N-15 N-16 N-18 N-19 N-20 N-21 N-23 N-24 N-25A N-25B N-26 N-29 N-31 N-32 N-34 N-35 N-36 N-37 N-38 N-39 N-40 N-41 N-45 N-46 N-47 N-48 N-49 N-50 N-51 N-52 N-54 N-55 N-59 N-60 N-63 N-65 N-67 N-68 N-69 N-71 N-72 N-73 N-74 N-81 N-82 N-84 N-86 N-87 N-94 N-96 N-102 N-103 N-105 N-110 N-111 N-112 N-117 N-124 N-132 N-133 N-134 N-135 N-138 N-141 N-144 N-149 N-150 N-151 N-155 N-156 N-165 N-204 N-205 N-250 N-267 N-285 N-300 N-301 N-302 N-303 N-304 N-305 N-306 N-307 N-311 N-320 N-321 N-322 N-330 N-370

'P' series	P530 P600 P610 P630

By role

Attack	YA-13 XA-16 A-17 Nomad YA-9

Bombers	YB-35 YB-49 B-62 BT B2T B-2

Drones	Q-4

Fighters	3A XP-56 P-61 XP-79 F-89 XFT F2T F-5/CF-5/CF-116 YF-17 F-18L F-20 YF-23

Reconnaissance	F-15 RF-61 RF-5 N-165 N-204

Trainers	T-38

Transports	Alpha Beta Gamma Delta C-19 C-100 YC-125 RT

Experimental	N-1M N-9M JB-1 MX-324 MX-334 M2-F2 M2-F3 HL-10 Tacit Blue X-4 X-21

Names

See also: TR-3

1955–1962 United States Air Force rocket and missile designations

Air-to-air missiles

1955–1961 sequence	MB-1 GAR-1 GAR-2 GAR-3 GAR-4 GAR-5 GAR-6 GAR-8 GAR-9 GAR-11

1961–1963 sequence	AIM-101

Other types

Undesignated types

See also: USAF missile designations 1947–51
United States tri-service missile and drone designations post-1962

USAAS/USAAC/USAAF/USAF bomber designations, Army/Air Force and Tri-Service systems

Original sequences
(1924–1930)

Light Bomber	LB-1 LB-2 LB-3 LB-4 LB-5 LB-6 LB-7 LB-8 LB-9 LB-10 LB-11 LB-12 LB-13 LB-14

Medium Bomber	B-1 B-2

Heavy Bomber	HB-1 HB-2 HB-3

Main sequence
(1930–1962)

B-1
B-2
B-3
B-4
B-5
B-6
B-7
B-8
B-9
B-10
B-11
B-12
B-13
B-14
B-15
B-16
B-17
B-18
B-19
B-20
B-21
B-22
B-23
B-24
B-25
B-26
B-27
B-28
B-29
B-30
B-31
B-32
B-33
B-34
B-35
B-36
B-37
B-38
B-39
B-40
B-41
B-42
B-43
B-44
B-45
B-46
B-47
B-48
B-49
B-50
B-51
B-52
B-53
B-54
B-55
B-56
B-57
B-58
B-59
B-60
B-61
B-62
B-63
B-64
B-65
B-66
B-67
B-68
RB-69
B-70
FB-111

Long-range Bomber
(1935–1936)

Non-sequential

Redesignated A-series	B-20 B-26

Tri-Service sequence
(1962–current)

See also: SR-71 (designation in bomber sequence)
2037 Bomber

1947–1951 United States Air Force rocket and missile designations

Air-launched

Air-to-air	AAM-A-1 AAM-A-2

Air-to-surface	ASM-A-1 ASM-A-2

Ground-launched

Surface-to-air	SAM-A-1

Surface-to-surface	SSM-A-1 SSM-A-2 SSM-A-3 SSM-A-4 SSM-A-5 SSM-A-6

Test vehicles

Launch test	LTV-A-1

Propulsion test	PTV-A-1

Rocket test	RTV-A-1 RTV-A-2 RTV-A-3 RTV-A-4 RTV-A-5

Types of missile

By platform	Air-launched ballistic missile (ALBM) Air-launched cruise missile (ALCM) Air-to-air missile (AAM) Air-to-surface missile (ASM) Ballistic missile Cruise missile Intercontinental ballistic missile (ICBM) Intermediate-range ballistic missile (IRBM) Shoulder-fired missile Submarine-launched ballistic missile (SLBM) Submarine-launched cruise missile (SLCM) Surface-to-air missile (SAM) Surface-to-surface missile (SSM)

By target type	Anti-ballistic missile (ABM) Anti-satellite weapon (ASAT) Anti-ship ballistic missile (ASBM) Anti-ship missile (AShM) Anti-submarine missile Anti-tank missile (ATGM) Land-attack missile (LACM)

By guidance	Active radar guidance Semi-active radar guidance Passive homing Track-via-missile Anti-radiation Command to line-of-sight guidance Command off line-of-sight guidance Pursuit guidance Beam riding Infrared guidance Laser guidance Unguided rockets Wire guidance TERCOM DSMAC Inertial guidance Astro-inertial guidance Satellite guidance Compass

Lists	List of military rockets List of missiles List of missiles by country List of anti-ship missiles List of anti-tank missiles List of ICBMs List of surface-to-air missiles

See also: Sounding rocket

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