The Q and R class were repeats of the preceding O and P class, but reverted to the larger J-, K- and N-class hull to allow for the inevitable growth in topweight. As they had fewer main guns than the J, K and Ns, some magazine space was replaced by fuel bunkers,^[1] allowing for some 4,675 nautical miles (8,658 km) to be made at 20 knots (37 km/h), over the 3,700 nmi (6,900 km) of their predecessors. Like the O and Ps, they were armed with what weapons were available; 4.7-inch (119 mm) guns on single mountings that allowed for only 40° elevation - therefore do not compare favourably on paper with many contemporaries. These ships used the Fuze Keeping Clock HA Fire Control Computer.^[2]

In the Q class, 'Y' gun could be removed, allowing for the carriage of additional depth charges and projectors, or the carriage of minesweeps.

The R class were repeats of the Qs, except that the officers' accommodation was moved from its traditional location right aft to the more accessible location amidships.^[1] This facilitated the change in watchkeepers in inclement weather; the main deck of a destroyer would often be entirely awash in heavy seas, and catwalks were not fitted to connect fore and aft until the V class ordered in 1941.

In surviving ships, the single 20 mm Oerlikon guns in the bridge wings were later replaced by hydraulically operated Mark V twin mountings. Rotherham, Raider and Rocket later had the Oerlikons and searchlight amidships replaced by four single QF 40 mm Bofors. The searchlight was later reinstated at the cost of depth charge stowage. Raider only had an additional pair of twin Mark V Oerlikon mounts added on the after shelter deck. Radar Type 290 was replaced by Type 291, and later by Type 293 in some ships. The centimetric wavelength Type 272 set was added on a platform between the torpedo tubes in Rotherham, Racehorse, Rapid, Raider and Roebuck, or at the foremast truck in other ships. Racehorse, Raider, Rapid, Redoubt and Relentless had Huff-Duff (High-frequency Direction-finder) added on a lattice mainmast.

Q class edit

R class edit

• Type 15 frigate – most surviving Q and R-class ships were given this conversion post-war.

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• English, John (2001). Obdurate to Daring: British Fleet Destroyers 1941–45. Windsor, UK: World Ship Society. ISBN 978-0-9560769-0-8.
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