The I-class ships were improved versions of the preceding H-class. They displaced at standard load and at deep load. The ships had an overall length of, a beam of and a draught of. They were powered by two Parsons geared steam turbines, each driving one propeller shaft, using steam provided by three Admiralty three-drum boilers. The turbines developed a total of and were intended to give a maximum speed of. Imogen only reached a speed of from during her sea trials. The ships carried enough fuel oil to give them a range of at. Their crew numbered 145 officers and ratings. The ships mounted four 4.7-inch Mark IX guns in single mounts, designated 'A', 'B', 'X' and 'Y' from bow to stern. For anti-aircraft defence, they had two quadruple mounts for the 0.5 inch Vickers Mark IIImachine gun. The I class was fitted with two above-water quintuple torpedo tube mounts amidships for British 21 inch torpedo| torpedoes. One depth charge rack and two throwers were fitted; 16 depth charges were originally carried, but this increased to 35 shortly after the war began. The I-class ships were fitted with the ASDIC sound detection system to locate submarines underwater.
Construction and career
The ship was ordered on 30 October 1935 from Hawthorn Leslie at Hebburn under the 1935 Naval Programme. She was laid down on 18 January 1936, launched on 30 December 1936, as the seventh Royal Navy ship to carry this name, and completed on 2 June 1937, at a contract price of £256,917, excluding items supplied by Admiralty such as armaments and communications equipment. Imogen was assigned to the 3rd Destroyer Flotilla of the Mediterranean Fleet upon commissioning and was initially based in Malta. Transferred to Gibraltar, she patrolled Spanish waters enforcing the policies of the Non-Intervention Committee during 1938. The ship was given a brief refit in Malta from 17 October–28 November 1938 and another at Sheerness Dockyard in August 1939. Imogen returned to the Mediterranean on 3 September, but was transferred to the Western Approaches Command for convoy escort duties two days later when Italy did not enter the war. Together with the entire 3rd Destroyer Flotilla, the ship was transferred to the Home Fleet in October. Together with her sister, she sank the on 13 October after the submarine attempted to sink the freighter. Whilst escorting the merchant ship to Barry, Imogen rescued survivors from the ships Louisiane and Bretagne. She was refitted at Liverpool between 20 October and 7 November and then rejoined Home Fleet. The following month, the ship came to the aid of the torpedoed battleship off the Butt of Lewis on 28 December. With her sister and the destroyer, Imogen sank after it had been spotted by the British submarine on 25 February 1940. During the Norwegian Campaign, the ship searched unsuccessfully for German ships, escorted ships of Home Fleet and troopships carrying Norwegian Army units from Kirkenes and Alta to Sjøvegan in mid-April. In mid-June, she escorted the aircraft carrier to Bermuda to work up. Off Duncansby Head during the night of 16 July, Imogen collided with the light cruiser in thick fog whilst bound for Scapa Flow. She was badly damaged, caught fire, and sank at position. Glasgow rescued 10 officers and 125 enlisted men, but 19 men were killed in the collision.
