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SM-62 Snark

Although unofficially designated a surface-to-surface ICM, the Snark was essentially a small, turbojet-powered, unmanned aircraft. It was designed to be fired from a short mobile launcher by means of two solid-fueled rocket boosters. Once air-borne, the Snark was powered by a single Pratt and Whitney J-57 turbojet I engine capable of cruising at Mach 0.9 to an altitude of approximately 150,000 feet. After a programmed flight of 1,500 to 5,500 nautical miles, the Snark's airframe separated from its nose cone, and the missile's nuclear warhead followed a ballistic trajectory to its target. Plans developed by the Strategic Air Command employed the Snark against enemy defensive systems, especially radars, to ensure the effective penetration of enemy territory by manned bombers

Throughout the late 1940s and early 1950s, work on the Snark missile program progressed very slowly as a result of both limited research and development (R&D) funding and the low national priority accorded to all guided missile programs. This situation changed dramatically on 8 September 1955 when President Dwight D. Eisenhower assigned the highest national priority to the intercontinental ballistic missile (ICBM) development program. Even though the Snark was not an ICBM, the Air Force ordered its development program accelerated along with that of the Atlas missile.

In August 1945, the AAF established a requirement for a 600 mph, 5,000-mile- range missile with a 2,000-pound warhead. In response to an Air Force solicitation for such a device, Northrop presented a proposal in January 1946 for a subsonic, turbojet-powered, 3,000-mile range missile. That March, the company received one-year research and study contracts for a subsonic and a supersonic missile with a range of 1,500 to 5,000 statute miles, and a 5,000-pound payload. Jack Northrop, the company president, nicknamed the former (MX-775A) Snark, and the latter (MX-775B) Boojum, both names from the pages of Lewis Carroll.

The 1946 Christmas budget reduction deleted the subsonic Snark from the AAF missile program, but retained the supersonic Boojum. But the matter did not end there. Jack Northrop personally contacted Carl Spaatz, Chief of the Air Arm, and others, to save the Snark. He promised development in two and one-half years, at an average cost of $80,000 for each of the 5,000-mile missiles in a 5,000-unit production run. The noted aircraft designer and manufacturer contended that it would take several years to develop the turbojet-powered missile, with 60 percent of the effort going into the guidance system. Before 1947 passed into history, USAF reconstituted the Snark program, slightly modified from the August 1945 specifications, at the same time relegating the Boojum to a follow-on status.

Air Materiel Command authorized 10 flight tests of the Snark, the first by March 1949. In July, General Joseph McNarney called the Snark America's most promising missile project. But the Army and the Navy criticized both the Snark and Navaho for their high cost relative to their overall priority and unproven concept. Even Air Force enthusiasm for the Snark cooled; in March 1950, the airmen reduced the program to the development of only its guidance system.

The company designated the initial version N-25. Larger and heavier than previous "flying bombs," Snark also possessed much greater performance; its J33 engine pushed it at a cruising speed of Mach .85 (with a maximum level speed of Mach .9) to a range of 1,550 statute miles. A B-45 mother ship controlled the N-25, which Northrop designed to be recovered by means of skids and a drag chute. The designers expected that recovering the test vehicles would cut the time and money required to develop the missile.

Numerous problems became apparent in testing the N-25 at Holloman Air Force Base. Despite a schedule calling for flight tests in 1949, the experimenters did not make the first attempted launch until December 1950. It failed. After another failure, the first successful flight took place in April 1951 when the missile flew 38 minutes before recovery. During this series of tests, the 16 sled-launched missiles flew 21 times, achieving a maximum speed of Mach .9 and a maximum endurance of 2 hours, 46 minutes. With the conclusion of these tests in March 1952, 5 of the 16 N-25s remained.

The prose description and a quick glance at a photograph of a Snark fails to highlight the uniqueness of the missile. The Snark flew in a nose-high flying altitude because it lacked a horizontal tail surface as did so many of Northrop's machines. Instead of conventional control surfaces (ailerons, elevation), the Snark used elevons. A profile view reveals that the missile also had a disproportionally small vertical tail.

To meet the toughest challenge for the program, guidance over the proposed intercontinental distances, Northrop proposed an inertial navigation system monitored by stellar navigation. Northrop accomplished the first daylight (ground) test of this stellar device in January 1948. This was followed by flight tests aboard B-29s in 1951-52. Between 1953 and 1958, 196 flight tests aboard B-45 aircraft provided about 450 hours of guidance experience. The large and heavy (almost one ton) guidance system worked, but not for very long. The company claimed that the Snark could achieve a CEP* of 1.4 nm.

In June 1950, the Air Force increased Snark requirements to include a supersonic dash at the end of the 5,500 nm mission (6,350 statute miles), a payload of 7,000 pounds (later reduced to 6,250 pounds), and a CEP of 1,500 feet. This key decision, increasing performance requirements, invalidated the N-25.

Northrop therefore produced a new design. Basically a scaled-up N-25, the N-69 was initially called "Super Snark." The new requirements that swept the N-25 aside for the larger and more difficult N-69 hurt the Snark program. As a result the program lost considerable time (38 months between the first flight of each). This overstates the impact somewhat, however, as difficulties with the guidance system as well as airframe sank the program.

The company lengthened the fuselage, sharpened the nose shape, replaced the external scoop with a flush scoop, and increased the launch weight. More noticeably, Northrop added a larger wing. Although Northrop slightly shortened the wing span, it broadened the wing by extending it further aft, thus increasing the wing area from 280 to 326 square feet. In addition, because wind tunnel and N-25 tests showed some instability in pitch (pitch-up), Northrop redesigned the wing with a leading edge extension, thereby giving the Snark wing its "saw tooth" shape. A J71 engine powered the "A," ''B," and "C" models before USAF adopted the J57 in December 1953 for the "D" models.

But testing was necessary before this could occur. First, the experimentors tested three unpowered dummy missiles with ballast to simulate the N-69. Then between November 1952 and March 1953, they flew four modified N-25s fitted with two 47,000-pound-thrust boosters. In contrast, the N-69A used twin, four-second duration, 105,000-pound-thrust boosters, while N-69C and later models relied on twin, four-second duration, 130,000-pound-thrust rockets.

But numerous problems beset the Northrop missile during testing. The Snark proved unstable in all but straight and level flight. Northrop compounded these difficulties when it took engineers off the Snark project to help the company's ailing, but priority, F-89 all-weather interceptor program. Despite the reduction of test vehicles to 13 (as of February 1953), the program exceeded its budget by $18.3 million. The movement of testing from Holloman to the Atlantic Missile Range in 1952, a move opposed by Northrop, also hindered the program. In fact, the slow construction of test facilities in Florida restricted testing between 1953 and 1957. There were also powerplant problems because the J71 engine exceeded its fuel consumption specifications, necessitating a number of engine changes. If these problems were not enough, the first missile delivered for flight tests was in serious disrepair.

The program also suffered numerous test failures. The initial launch attempt on 6 August 1953 failed, as did the next four. On 3 June 1954, the missile flew three and one-half hours but exploded on landing. While USAF recovered 10 N-25s on its 21 flights, the first successful N-69 recovery occurred on the 31st flight on 2 October 1956. The lack of recoveries retarded the testing of the N-69. Northrop completed these tests by May 1955, well after the Snark's tentative activation date of April 1953 and operational date of October 1953.

The problems grew worse. By May 1955, wind tunnel and flight tests indicated that Northrop's operational concept, terminal dive of the missile into the target, would not work because of inadequate eleven control. Five flight tests of the IC, a nonrecoverable radio-controlled missile with fuselage speed brakes (designed to test the Snark from launch into the target) confirmed these findings. In July 1955, the Air Force accepted the company's proposal for a different delivery concept involving a nose which detached from the airframe near the target and then followed a ballistic trajectory. The redesigned missile (N-69C, modified) first flew on 26 September l955

These aerodynamic, cost, and scheduling problems brought the missile under fire and generated unfavorable publicity. One bit of ridicule which outlived the program dubbed the waters off Canaveral "Snark infested waters" because of the numerous crashes. (In fact, to some, this may well be the most memorable aspect of the entire program.) At the other extreme, a Snark in December 1956 flew too far, that is, it failed to respond to control and was last seen heading toward the jungles of Brazil As one Miami paper put it, with apologies to Henry Wadsworth Longfellow. "They shot a Snark into the air, it fell to the earth they know not where." In 1982, a Brazilian farmer found the errant missile.

More importantly, Strategic Air Command (SAC), the intended user of the missile, began to express doubts about the Snark by late 1951. Although some may suspect the motives of a unit dominated by bomber pilots regarding a pilotless bomber that would take the man out of the machine, valid questions concerning the weapon's reliability and vulnerability emerged at this point. As early as 1951, SAC decried Snark's vulnerability both on the ground and in the air. On the ground, the missile would be based at unhardened fixed sites. In the air, the subsonic (Mach .9) Snark lacked both defensive armament and the ability for evasive maneuver. Indeed, it is difficult to quarrel with the 1954 SAC command position, which was "conservative concerning the integration of pilotless aircraft into the active inventory in order to insure that reliance is not placed on a capability which does not in fact exist." But some SAC officers in 1951 saw value in the Snark program as a way to get the command into the missile business. Or perhaps they just wished to make the most of a bad situation.

Criticism of the Snark came from other quarters as well. In early 1954, a blue ribbon panel, The Strategic Missile Evaluation Committee, found important aspects of all three American long-range missile programs (Snark, Navaho, and Atlas) unsatisfactory. The committee concluded that, in general, the missiles' CEPs were outdated and their bases were vulnerable. The panel assessed the Snark as an "overly complex" missile which would not become operational until "substantially later" than scheduled.

The panel went on to make three recommendations. First, it recommended that USAF employ a variety of means to assist heavy bombers: area decoys, local decoys, and ECM (electronics countermeasures). Second, it suggested that USAF extend missile CEP requirements from one quarter nm to three-to-five nm. Clearly, this relaxation made sense in view of the much greater warhead capability soon to be available with the evolution from atomic to hydrogen explosives, and the accuracy limitations of the existing guidance systems. (By mid-1954, USAF had loosened Snark's CEP requirement from 1,500 to 8,000 feet.) Third, the panel recommended simplification of the Northrop vehicle, entailing cancellation of both the Northrop and North American celestial navigation systems. The committee estimated that Northrop could produce a simplified Snark by 1957 with quantity production in 1958-59.

But the Snark program did not appreciably improve. In fact, test problems demonstrated serious deficiencies in the weapon. In 1958, General Irvine of Air Research and Development Command (ARDC) cited the Snark as an outstanding example of unwarranted funding; and General Power, Commander of SAC, noted that the missile added little to the command's strength. The latter wanted a reevaluation of Snark in order to either correct deficiencies or terminate the program.

Despite Air Force reservations about the Snark, journalists presented the case for the Northrop missile in the aviation press in the period 1955-58. They emphasized the missile's major advantages, chiefly resulting from the fact that it was a one-way, unmanned weapon. Besides not requiring a tanker fleet, advantages included fewer requirements for ground handling, repair, and safety. Snark's advocates noted that it could fly as fast as contemporary bombers, could be programmed for evasive maneuvers (so they claimed), and could be adapted for low-level (500-foot) operations. Suggestions that would reduce prelaunch vulnerability included rotating the missiles between sites (more sites than missiles) and deploying them on old aircraft carriers. But the crucial argument for Snark focused on low cost. About 1/8th to 1/l0th the size of a B-52, the Snark cost as little as 1/20th as much as the Boeing bomber. Simply put, the Snark was cost effective.

Meanwhile, the program lumbered along. Northrop designed the "D" model Snark as a recoverable vehicle equipped with a 24-hour stellar-inertial system. In the most visible change, Northrop added two pylon tanks carrying a total of 593 gallons of fuel to the wing. The overall result increased the Snark's empty weight from 16,616 pounds ("C") to 20,649 pounds ("D") and the gross flying weight from 36,074 pounds to 44,106 pounds. The N-69D first flew in November 1955, but did not accomplish its first successful stellar-guided flight until October 1956.

The "E" model followed shortly. While Northrop cut 2,000 pounds from the "D's" empty weight, the ''E" weighed 5,000 pounds more at gross flying weight. The company first launched the N-69E, the prototype vehicle for the SM-62 (the operational designation, "strategic missile"), in June 1957 (it crashed within seconds), initially with a workable rudder that it later deactivated. An Air Force crew launched its first Snark on 1 October 1957. These operations by SAC crews illustrated the Snark's severe problems. Of the first seven Air Force launches, only two reached the drop zone and only one of these impacted within four miles of the aiming point.

The central problems remained guidance and reliability. While the first full-range test revealed that existing maps mislocated Ascension Island, this meant little to the Snark program because of the missile's gross inaccuracy. On flights out to 2,100 miles, the Northrop missile averaged a CEP of 20 miles. The most accurate of seven full-range flights between June 1958 and May 1959 impacted 4.2 nm left and .3 nm short of the target; in fact, it was the only one to reach the target area, and one of only two missiles to pass the 4,400 rim distance mark. Not until February 1960 did Snark successfully complete a guidance trial. Based upon the last ten launches in the program, the guidance system showed less than a 50 percent chance of performing to specifications. In addition, the guidance system, along with the control system, accounted for about half the test failures; the other half were attributed to random factors. Test results indicated that Snark had only a one in three chance of getting off the ground and only one of the last ten launches went the planned distance.

In the mid and late 1950s, as more progress was made toward the deployment of the Snark ICM, SAC began to lose enthusiasm for the Snark weapon system, due primarily to two factors. First, SAC was greatly concerned with the relatively low speed of the Snark and its inability to operate in the stratosphere, characteristics which rendered the missile highly vulnerable to enemy interception and destruction.

Secondly, and of even greater importance, was the Snark's poor test performance record. Throughout the Snark test program, initiated in 1952, numerous launch and guidance failures had raised serious questions regarding the weapon system's reliability. In light of these liabilities, SAC advocated termination of the program. On 16 December 1958, General Thomas S. Power, Commander in Chief Strategic Air Command, informed General Curtis E. LeMay, the Air Force Vice Chief of Staff, that: . . . the limited operational capability of this system adds little or nothing to the strategic offensive force and I believe that a re-evaluation of this program is in order . . . either we should take necessary action to integrate the Snark into the strategic inventory with a capability compatible with our concept of operating or . . . take immediate action to cancel the program.

Nevertheless, the Air Force began to incorporate the Snark into its inventory. While responsibility for the development and testing of guided missiles rested with the Air Research and Development Command, (predecessor of today's Air Force Materiel Command), the Strategic Air Command maintained a close liaison with the various missile programs by presenting SAC requirements, offering technical assistance, and sending representatives to various conferences, meetings, and field demonstrations. At the same time, SAC was actively engaged in developing operations plans for those guided missiles destined for eventual deployment with the command. Thus, on 10 December 1956, SAC published a Snark operational plan that outlined the mission and requirements for equipping, manning, siting, activating, and operating Snark units. Two months earlier, on 22 October, the command had established a Strategic Missile Site Selection Panel to survey potential missile site locations. The panel considered range, expected target assignment, and the overall capabilities of the Snark ICM system when surveying sites. On 21 March 1957, the Air Force, acting on the recommendation of the Strategic Missile Site Selection Panel, designated Presque Isle AFB, Maine, as the site for the first Snark missile base. Two months later, on 17 May, the Air Staff selected Patrick AFB, Florida, as the training and operational testing locale for the Snark ICM. To carry out this important dual assignment at Patrick AFB, SAC activated the 556th Strategic Missile Squadron on 15 December 1957, making it SAC's first Snark and first strategic surface-to-surface guided missile squadron. On 27 June 1958, little more than six months after being activated, the 556th SMS successfully launched its first Snark from Cape Canaveral, Florida -- shortly before USAF deactivated the unit.

But in November 1959, within a year of Power's request for a program evaluation, SAC recommended cancellation of Snark (the recommendation was endorsed by ARDC). Headquarters USAF, however, rejected that proposal. Despite General Power's recommendation, the Air Force and the Department of Defense decided to continue a limited program for the operational deployment of one Snark squadron to acquire some missile capability until ballistic missiles became available in quantity. On 1 January 1959, SAC activated the 702nd Strategic Missile Wing (ICM-Snark) at Presque Isle AFB, Maine, and assigned it to the Eighth Air Force, thus making it the first SAC missile wing to be assigned to a numbered air force. The 556th SMS at Patrick AFB was assigned to the 702d SMW on 1 April 1959 and was scheduled to move to Presque Isle in July, but SAC inactivated the squadron on 15 July 1959 before the move could be consummated. As a result of this action and the subsequent cancellation of the programmed activation of the 702nd Missile Maintenance Squadron, the 702nd SMW was put in the unique position of having no assigned subordinate units. All operational and maintenance functions associated with the Snark ICM were handled by the 702nd SMW's deputy commander for missiles. The 702d SMW placed the first Snark ICM on alert on 18 March 1960 and by the end of fiscal year 1960, a total of four Snark missiles were on strategic alert. Yet, it was not until 28 February 1961 that SAC was able to declare the 702d SMW operational.

But the Snark was living on borrowed time. Shortly after taking office in 1961, John F. Kennedy scrapped the project. The Strategic Air Command's negative evaluation of the Snark's potential was reinforced on 28 March 1961 when President John F. Kennedy, in a special defense budget message, directed the phase out of the missile because it was "obsolete and of marginal military value" relative to ballistic missiles. The President cited the weapon's low reliability (a particularly sore point to his Secretary of Defense), inability to penetrate, lack of positive control, and vulnerable, unprotected launch sites. Accordingly, in June 1961 [various sources report either 2 June or 25 June], SAC inactivated the 702d Strategic Missile Wing at Presque Isle AFB less than four months after it had been declared operational.

Surely the unit's and Snark's service trust rank as one of the briefest in peacetime US military history. While the operational life of the Snark ICM was extremely short, the program was not without its benefits. Chief among these was the experience gained by the Strategic Air Command in planning and carrying out the activation, training, and deployment of guided missile squadrons and wings. Such experience would be invaluable to SAC as it prepared for the deployment of such follow-on missile weapon systems as the Atlas, Titan, Jupiter, and Minuteman.

Specifications

Sources and Resources

  • "Evolution of the Cruise Missile" by the USAF


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