I-class destroyer


The I-class destroyers were a group of nine destroyers, including a flotilla leader, built for the Royal Navy during the 1930s. Four similar ships were ordered by the Turkish Navy, of which two were purchased for the Royal Navy, bringing the number of these ships British service to 11—although three of the original ships had been lost by the time Inconstant and Ithuriel were commissioned. The I-class served in World War II and six were lost, with a seventh ship being written off.

Design

The Is were a repeat of the preceding H class, except that they had ten torpedo tubes instead of eight. They incorporated the new bridge and wheelhouse layout as tested in and . Inglefield also had a larger tripod foremast, her sisters having pole masts. The extra weight of the torpedo tubes and the fitting of minesweeps and depth charge gear on the same hull as the H class, caused a loss of stability, needing ballast when bunker levels were low.
All ships were fitted for minesweeping and with depth charges and Asdic for anti-submarine work and were capable of conversion to minelayers. For this, they landed 'A' and 'Y' 4.7 inch guns, the torpedo tubes and their minesweeps, allowing carriage of up to 60 mines but only four ships were used like this.

Turkish ships

The Turkish I-class ships were of a similar design to their British counterparts but shipped only eight torpedoes like the British H class.

Wartime modifications

Early war modifications involved replacing the after bank of torpedoes with a QF 12-pounder anti-aircraft gun, cutting down the after funnel and mainmast to improve its field of fire and adding a pair of QF 20 mm Oerlikon guns in the bridge wings. Radar Type 286, a metric wavelength surface-warning set, was added as it became available and the ineffective multiple Vickers machine guns were replaced with Oerlikons; the central tube was deleted from the torpedo launchers to lessen topweight. Icarus lost 'Y' gun to stow extra depth charges and their mortars. Surviving ships received a third pair of Oerlikons, added abreast the searchlight position and the 12-pounder was deleted to increase depth charge stowage. In some ships, 'A' gun was replaced with a Hedgehog forward-throwing A/S weapon but this alteration seems to have been reversed at a later stage. Ilex, Intrepid, Impulsive and Isis had 'B' gun removed and two QF 6-pounder 10 cwt guns were added on the twin mounting Mark I* along with a Hedgehog, the former for anti-E boat work.
Inglefield later had the second bank of torpedo tubes re-instated but like her sisters, the central tube was removed. A AA gun was added in lieu of 'X' gun and she had six Oerlikons. Type 291 radar was later added at the foremast head as well as Huff-Duff in some ships.
The ex-Turkish ships were modified along similar lines to their I-class sisters. Inconstant later received Type 270 radar, a centimetric wavelength target-indication set, in lieu of the director and rangefinder on the bridge. Again, eventually six Oerlikons were carried.

Ships

Pennant
number		ShipBuilderLaid downLaunchedCommissionedFate
D03 †John Brown & Company, Clydebank9 March 193626 November 19363 May 1937Sold for scrap, 29 October 1946.
D61John Brown & Company, Clydebank9 March 193628 January 19377 July 1937Sold for scrap, 1948.
D44Hawthorn Leslie & Company, Hebburn18 January 193630 October 19362 June 1937Collided with the cruiser 16 July 1940 and sunk.
D09Hawthorn Leslie & Company, Hebburn29 January 193611 December 193630 June 1937Severely damaged by air attack, 29 May 1941, sunk by torpedoes from
D11 †J. Samuel White, Cowes9 March 19361 March 193729 January 1938Sold for scrap, 22 January 1946.
D02Cammell Laird & Company, Birkenhead29 April 193615 October 193625 June 1937Sunk by German radio-controlled glide bomb off Anzio, 25 February 1944
D10 †J. Samuel White, Cowes6 January 193617 December 193629 July 1937Sunk by German Ju 88 bombers off Leros, 26 September 1943
D87Yarrow & Company, Scotstoun5 February 193612 December 19362 June 1937Mined and sunk off Normandy beaches, 20 July 1944.
D16Ivanhoe †Yarrow & Company, Scotstoun12 February 193611 February 193724 August 1937Mined and sunk off Texel, 1 September 1940

† = fitted as minelayers

Turkish ships

Four ships were ordered for the Turkish Navy in 1938. Upon the outbreak of war, two were purchased by the British but two were delivered to Turkey in 1942 as the Sultanhisar and the Demirhisar.
Pennant
number		ShipBuilderLaid downLaunchedCompletedFate
H49
Vickers, Barrow24 May 193924 February 194124 January 1942Acquired 14 November 1941, returned to Turkey 9 March 1946, sold for scrap, 1960.
H05
Vickers, Barrow24 May 193915 December 19403 March 1942Bombed at Bône 28 November 1942 and beached. Written-off 27 February 1943 and hulked. Sold for scrap, 25 August 1945.
H87William Denny, Dumbarton21 March 193917 December 194028 June 1941Delivered to Turkey in 1942, decommissioned 1960
H80William Denny, Dumbarton193919411942Delivered to Turkey in 1942, decommissioned 1960