Type 15 frigate

The Type 15 frigate was a class of British anti-submarine frigates of the Royal Navy. They were conversions based on the hulls of World War II-era destroyers built to the standard War Emergency Programme "utility" design.

Raison D'être

By 1945 the wartime "utility" vessels were obsolescent as destroyers due to their relatively small size and makeshift armament. Future construction would be based on ever larger vessels, such as the Battle class and "Daring" class. Rapid advances in German U-boat technology with the 17 knot Type XXI and 19 knot Type XXVI rendered even some of the most modern Royal Navy escorts obsolete. This technology was being put into production by the Soviet Navy in the form of the Whiskey class submarine. The Royal Navy began designing and constructing new fast anti-submarine frigates of the Type 12 and Type 14 design to counter this threat. However, it would be some time before these vessels could be brought into service and budget constraints limited the number of new hulls that could be constructed. The solution to the problem lay in the 47 "utility" destroyers that remained in Royal Navy service, most of which were less than a few years old and had seen little war service. Accordingly, plans were drawn up to convert these vessels into fast anti-submarine frigates incorporating as many lessons learned during wartime experience as possible.

Conversion

Before conversion began, all superstructure, weaponry, masts and equipments were removed and the machinery was overhauled. The forecastle was extended backwards to leave only a small quarterdeck, providing much improved accommodation, the lack and poor quality of which had been a source of constant problem for large wartime crews. A new single-level superstructure incorporating the fully-enclosed bridge (a novelty in a British escort ship), operations room and a sonar room was added spanning the full width of the hull in front of the funnel. The new superstructure layout allowed the crew to fight the ship without having to expose themselves to the elements, and was increasingly important in the age of nuclear weapons. New lattice masts were provided to carry the range of radars, HF/DF and communications equipment that were now required for a naval escort. "Troubridge", "Ulster" and "Zest" were fitted with a new design of bridge that would be adopted in all subsequent British frigates up to the "Leander" class. This bridge had angled sides and raked windows, to allow good all-round vision and cut down on internal reflections at night.

A completely new suite of armaments and electronics was added, befitting their role as fast anti-submarine frigates. The armament was centred around a pair of Mark 10 "Limbo" A/S mortars. These three-barrelled weapons were based on the wartime "Squid",and were mounted on the quarterdeck aft, where they were best protected from the weather. They had a 360° field of fire and were automatic in operation. It had been intended to carry a new anti-submarine weapon, the Mark 20E torpedo, in a pair of trainable tubes on each beam, but this weapon was a failure and the tubes, where fitted, never received weapons and were later removed. "Rapid", "Roebuck" and all V and W class ships carried Squids in lieu of Limbo due to insufficient funds existing to fit all ships with Limbo. For self defence, a twin 4 inch gun on a Mounting Mark XIX was carried aft, controlled by the MRS-1 Close Range Blind-Fire director (CRBF). Behind the bridge was fitted a twin 40 mm Bofors gun on a "utility" Mounting Mark V.

Many vessels were used during their peacetime service as seagoing training ships, for which purposes the 40 mm gun was removed and a large open bridge was added above the rounded face of the existing bridge. "Undaunted" was built with a flight deck aft, and was used for trials of the Fairey Ultralight and Saunders Roe P531 helicopters. "Undaunted" became the first frigate to carry and operate a helicopter. "Grenville" had a flight deck fitted in 1959, but this was later removed.

hips

23 ships were converted, in a programme that lasted between 1949 to 1957

ee also

*War Emergency Programme destroyers: The destroyer building programme that the Type 15 frigates were converted from.
*Type 16 frigate: A more limited conversion of destroyer hulls than the Type 15.
*HMCS "Algonquin" and HMCS "Crescent" were converted into similar ships for the Royal Canadian Navy.
*The Royal Australian Navy converted four out of five of their Q class destroyers to Type 15 frigates from 1953-57. The other ship, HMAS "Quality", was scrapped in 1958.

Bibliography

* "Royal Navy Frigates 1945-1983" Leo Marriot, Ian Allan, 1983, ISBN 0-7110-1322-5

Notes