FF-1052 Knox-class
Summary
| Origin country | 🇺🇸 United States |
| Category | Frigate |
| Subtype | Frigate |
| Manufacturer | Todd Shipyard |
| Year commissioned | 1969 |
| Units | Knox, Roark, Gray, Hepburn, Connole, Rathburne, Meyerkord, W. S. Sims, Lang, Patterson, Whipple, Reasoner, Lockwood, Stein, Marvin Shields, Francis Hammond, Vreeland, Bagley, Downes, Badger, Blakely, Robert E. Peary, Harold E. Holt, Trippe, Fanning, Ouellet, Joseph Hewes, Bowen, Paul, Aylwin, Elmer Montgomery, Cook, McCandless, Donald B. Beary, Brewton, Kirk, Barbey, Jesse L. Brown, Ainsworth, Miller, Thomas C. Hart, Capodanno, Pharris, Truett, Valdez, Moinester |
Operators
Technical specifications
| Displacement | 4130 tons |
| Range | 4500 km at 20 knots |
| Crew | 257 members |
| Width | 14.25 m (46.8 ft) |
| Length | 134.0 m (439.6 ft) |
| Air Park |
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| Propulsion | 1 × Westinghouse steam turbine, 2 × 1,200 psi boilers, 35,000 shp |
| Thrust | 2250 hp |
| Armament |
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| Maximum speed | 27 knots |
Description
The Knox class was a series of 46 anti-submarine warfare ships built for the United States Navy between 1965 and 1974. Designated SCB No. 199C, the design was developed as a follow-on to the Garcia and Brooke classes. Originally classified as ocean escorts (DE), the ships were redesignated as frigates (FF) in 1975. The lead ship, USS Knox, was commissioned in 1969. Although 55 units were planned, nine were canceled in 1968 and 1969.
The class utilized a steam turbine powerplant with two 1,200 psi boilers driving a single shaft. It was the final US Navy destroyer-type design to use steam propulsion. The hull was designed around the AN/SQS-26 bow-mounted sonar, and the ships were lengthened during the design phase to accommodate conventional boilers instead of the originally planned pressure-fired units. Beginning in 1979, the ships were refitted with heightened "hurricane bows" to reduce deck wetness and protect forward armament. A subset of the class, starting with USS Joseph Hewes, featured additional staterooms to serve as flagships.
Primary sensors included the AN/SQS-26 low-frequency sonar for direct path and convergence zone operations. Later modifications added the AN/SQS-35 variable depth sonar and the AN/SQR-18 towed array sonar. Armament as built consisted of a 5-inch/54 caliber Mark 42 gun, an eight-round ASROC launcher, and Mark 32 torpedo tubes. Aviation facilities were originally designed for the QH-50 DASH drone but were later modified to support the manned SH-2 Seasprite LAMPS I helicopter. Defensive systems were updated over the service life, with many units receiving the RIM-7 Sea Sparrow system and later the Phalanx CIWS. Offensive capabilities were expanded by modifying the ASROC launcher to fire Harpoon anti-ship missiles.
The United States Navy retired the Knox class between 1991 and 1994 due to operating costs and the requirement for updated anti-submarine capabilities. While many were scrapped or sunk as targets, others were transferred to the navies of Egypt, Greece, Mexico, Thailand, Turkey, and Taiwan. Spain constructed a modified variant known as the Baleares class, which replaced the helicopter facilities with a Mk 22 launcher for Standard missiles. In the Republic of China Navy, the ships were designated as the Chi Yang class; several of these vessels were updated with SM-1 missiles and combat systems recovered from retired Gearing-class destroyers. Two units remain in active service with the Egyptian Navy.