(Note: drawing contains some parts taken from Shipbucket.com)
|Performance||Speed (max)||32 knots|
|Speed (cruising)||20 knots|
|Endurance||4,000 nm @ 20 knots|
|Armament||Guns||2 4 inch L62 Mark XXIV, 4 40mm|
In 1955, the Royal Navy had reached a point where it had a satisfactory class of destroyers under construction for general purpose and ASW work and a pre-existing collection of smaller ships that served a general "presence" role. What was lacking was an air defense ship. The ever-growing presence of nuclear weapon made a massed strike of the kind that had destroyed the German Navy unlikely; instead a single nuclear delivery from high altitude appeared the most plausible threat. In common with most other navies, the Royal Navy decided that anti-aircraft missiles offered the best form of defense against such an attack. The problem the Navy faced was that, as they looked at the missile systems available for naval use, the launch systems appeared very vulnerable. All the missile systems being designed used rail launchers that were vulnerable to blast and weather damage. In addition, the rail launchers couldn't be kept loaded without risk of serious environmental degradation of the missiles, yet loading the rails would take up valuable time from the critical need to shoot the bomber down before itcould release its bomb.
Based on work being carried out by the British Aircraft Corporation, the Royal Navy adopted a different solution. They housed their missiles in vertical silos in the midships portion of the new ships, the silos being held partly in a deckhouse and partly inside the upper deck of the hull. In order to reduce length and to provide the energy needed for a vertical launch, the new missile, called Sea Slug, used four boosters, arranged around the missile second stage. This provided a design that was compact in terms of length but very bulky in terms of diameter. In fact, the Sea Slug silo had to be more than six feet in diameter to accommodate the missiles. Combined with arrangements to vent the exhaust gases as the missiles were fired, this restricted the number of missiles that could be fitted into the allocated area to twelve.
The Cleopatra class was based on the Boadicea class but with drastic changes. The hull was lengthened by 25 feet, the after 4 inch L62 gun was moved form the midships position to the stern. The limbos and their handling rooms were deleted to make room for the repositioned gun. A pylon mast was installed forward of the missile installation to carry a long range search radar with two missile guidance radars placed, one on each side of the mast. The extra space allowed a second 4 inch L62 gun to be worked in where the twin 40mm mount had originally been placed. This gave rise to a very unconventional appearance in which the bridge was actually ahead of and below the 4 inch gun. The 40mm mount was moved amidships and doubled up to give 4 40mm guns in two twin mounts.
The first Cleopatra class was ordered in 1957 with a second in 1958 and two more in 1959. Although construction proceeded quickly, development of the missile system did not and vertical launch proved to be very troublesome. The primary problem was getting the missile to turn in the right direction and be captured by the guidance radar after launch. Also, Sea Slug was afflicted with many problems including erratic booster separation causing the missile to tumble out of control. These problems took almost four years to sort out and the first Cleopatra did not commission until the end of 1963 with the other three following in 1964.
The Cleopatras did not receive good publicity when originally revealed. They seemed weak and under-armed compared with their Indian, Australian and American rivals. Professional naval designers though were more complimentary, recognizing that the British had built a functional if not exciting air defense ship on only just over 2,000 tons. This was approximately half the displacement of the Indian Godavari class. Also, the vertical launch system allowed the ships to carry their missiles ready for use and in protected locations. All in all, the Cleopatra's were much under-rated ships and, as their abilities became better recognized, opinion on them changed.
|Cleopatra||1957||1957||1959||1963||Sunk by Argentine air attack 5/4/1982|