SM-64 Navaho

From Wikipedia, the free encyclopedia

Navaho missile on launch pad
Navaho missile on launch pad
Navaho on display at CCAFS, Florida
Navaho on display at CCAFS, Florida

The North American SM-64 Navaho was a supersonic intercontinental cruise missile project built by North American Aviation. The program ran from 1946 to 1958 when it was cancelled in favor of the Intercontinental Ballistic Missile.

Contents

[edit] Development

The Navaho program began as part of a series of guided missile research efforts started in 1946. Designated MX-770, the original intent of the program was the development of a winged V-2 missile that could deliver a nuclear (fission) warhead over a distance of 500 miles. This was more than double the range of the V-2 as well as having a larger payload. Design studies showed the promise of still greater ranges and by 1950 the vehicle had evolved from a 500 mile ground launched winged V-2, to a 1,000 mile range ramjet powered winged V-2, to a 1,500 mile air-launched, ramjet-powered, winged V-2 (actually designated XSSM-A-2), to finally a 3,000 mile plus rocket boosted ramjet powered cruise missile. The design evolution finally ended in July of 1950 with the issuing by the Air Force of Weapon System 104-A. Under this new requirement the purpose of the program was the development of a 5,500 mile range nuclear missile.[1]

Under the new requirements of WS-104A, the Navaho program was broken up into three guided missile efforts. The first of these missiles was the North American X-10, a flying subrange vehicle to prove the general aerodynamics, guidance, and control technologies for vehicles two and three. The X-10 was essentially an unmanned high performance jet, powered by two afterburning J-40 turbojets and equipped with retractable landing gear for take off and landing. It was capable of speeds up to Mach 2 and could fly almost 500 miles. Its success at Edwards AFB and then at Cape Canaveral set the stage for the development of the second vehicle: XSSM-A-4, Navaho II, or G-26.

Step two, the G-26, was a nearly full-size Navaho nuclear vehicle. Launched vertically by a liquid-fuel rocket booster, the G-26 would rocket upward until it had reached a speed of approximately Mach 3 and an altitude of 50,000 ft. At this point the booster would be expended and the vehicle's ramjets ignited to power the vehicle to its target. The G-26 made a total of 10 launches from Launch Complex 9 (LC-9) at Cape Canaveral Air Force Station (CCAFS) between 1956 and 1957. Launch Complex 10 (LC-10) was also assigned to the Navaho program, but no G-26's were ever launched from it (it was only used for ground tests of the planned portable launcher).

The final operational version, the G-38 or XSM-64A, was the same basic design as the G-26 only larger. It incorporated numerous new technologies: Titanium, gimballed rocket engines, Kerosene/Lox fuel combination, full solid-state, etc. None were ever flown, the program being cancelled before the first example was completed. The advanced rocket booster technology went on to be used in other missiles including the intercontinental ballistic missile Atlas and the inertial guidance system was later used as the guidance system on the first U.S. nuclear powered submarines.

Officially, the program was canceled on July 13th 1957 after the first four launches ended in failure. In reality the program was obsolete by mid-1957 as the first Atlas ICBM began flight tests in June and the Jupiter and Thor IRBMs were showing great promise. These ballistic missiles however would not have been possible without the liquid fuel rocket engine developments accomplished in the Navaho program. The launch of the Soviet Satellite Sputnik in August 1957 only finished Navaho as the Air Force shifted its research money into ICBMs.

The Soviet Union had been working on parallel projects, The Myasishchev "Buran" and Lavochkin "Burya" and a little later, the Tupolev Tu-123. The first two types were also large rocket-boosted ramjets while the third was a turbojet-powered machine. With the cancellation of the Navaho and the promise of ICBMs in the strategic missile role, the first two were canceled as well, though the Lavochkin project, which had some successful test flights, was carried on for R&D purposes and the Tupolev was reworked as a big, fast reconnaissance drone.

The missile is named after the Navajo Nation and is in keeping with North American Aviation's habit of naming projects with code names starting with the letters "NA".

[edit] Operators

[edit] Survivors

The only Navaho missile in existence is currently displayed outside the south entrance gate of the Cape Canaveral Air Force Station, Florida.

[edit] Specifications

General characteristics

  • Length: 67 ft 11 in (20.7 m)
  • Wingspan: 28 ft 7 in (8.71 m)
  • Height: ()
  • Loaded weight: 64,850 lb (29,420 kg)
  • Powerplant:
    • 2× XRJ47-W-5 ramjets, 15,000 lbf (67 kN) each
    • 2× XLR83-NA-1 rocket boosters, 200,000 lbf (890 kN) each

Performance

Armament

  • 1 × nuclear warhead

[edit] References

  1. ^ *Gibson, James N. "The Navaho Missile Project/ The Story of the Know-How missile of American Rocketry," Altglen, PA, Schiffer Publishing, 1996, ISBN 0-7643-0048-2.

[edit] External links

Wikimedia Commons has media related to:

[edit] See also

Comparable aircraft

Related lists

Languages