HMS Medway (Pennant F25) was the first purpose-built submarine depot ship constructed for the Royal Navy. She was built by Vickers Armstrong at Barrow-in-Furness during the late 1920s. The ship served on the China Station before the Second World War and was transferred to Egypt in early 1940. Ordered to evacuate Alexandria in the face of the German advance after the Battle of Gazala in May 1942, Medway sailed for Lebanon at the end of June, escorted by a light cruiser and seven destroyers. Her strong escort could not protect her; on 30 June a German submarine torpedoed and sank her.
Medway was designed to support up to 18 and s in peacetime and an additional three submarines during wartime. She carried three QF 4-inch Mk IV deck guns as spares together with 144 210NaN0 torpedoes to resupply her submarines. The ship proved to be less top-heavy than anticipated and had the enormously high metacentric height of 13feet at full load. Built with bilge keels only 12inches deep, Medway once rolled 42° each way with a period of nine seconds, losing her main topmast. Her bilge keels were subsequently increased in depth to 36inches.
She was 580feet long overall and had a beam of 85feet and a draft of 21feet.[1] The ship displaced at standard load and up to at (full load).[2] Her crew numbered 400 officers and ratings; she could also accommodate up to 1,335 additional men.[1]
The ship was powered by MAN diesel engines rated at 8000bhp, driving two shafts, and had a top speed of about 15kn. Medway carried 810LT of diesel fuel for herself and an additional 1880LT for her submarines. Figures for her range are not available. The ship had five 560kW diesel generators for electrical power and special provisions to recharge submarine batteries.[1]
She was armed with two low-angle 4inches guns in single mounts and four quick-firing Mk V 4-inch anti-aircraft guns, also in single mounts. The latter guns were controlled by a High-Angle Control System mounted above the bridge. Medway was protected by an internal anti-torpedo bulge which incorporated a water jacket of . Amidships a 1.5inches torpedo bulkhead was located 13 feet inboard that inclined outwards above the waterline.[2] The main deck was 1.5 inches thick amidships.[1]
Medway was ordered on 14 September 1926 as part of the 1925/26 Naval Estimates.[3] The ship was laid down in April 1927 by the Vickers Armstrong shipyard in Barrow-in-Furness. The ship was launched on 19 July 1928. Captain Colin Cantlie was appointed as the first commander of the new ship on 1 January 1929. The ship was completed on 3 July 1929.[4]
After completion, HMS Medway began Harbour Acceptance Trials and Sea Acceptance Trials, known in the Royal Navy as HATs and SATs. A report in The Singapore Free Press and Mercantile Advertiser on 27 July 1929 notes that HMS Medway was undergoing trials.[5]
HMS Medway served on the China Station before the start of the Second World War. She had taken over from HMS Titania in 1929/30 as the submarine depot ship for the 4th Submarine Flotilla. HMS Medway took her place in Hong Kong as the depot ship for the 4th Submarine Flotilla.[6] Under the command of Capt. Colin Cantlie HMS Medway sailed to Hong Kong with six O-Class submarines of the Odin group. They were:
The submarine flotilla was enlarged in 1930.[7]
HMS Medway was under refit at Singapore from September 1939 through February 1940. Upon completion of the refit, Medway sailed for Hong Kong where she remained until she departed for Alexandria on 2 April. She arrived there on 3 May and thereafter supported the 1st Submarine Flotilla, which operated in the Eastern Mediterranean.[8]
Two years later, Vice-Admiral Henry Harwood, Commander-in-Chief, Mediterranean Fleet, ordered all non-essential ships to leave Alexandria in June 1942 as he was preparing to demolish the port facilities there to prevent their capture by the advancing Panzer Army Africa. Medway loaded stores and 1,135 personnel on 29 June to establish a new base at Beirut, Lebanon and sailed later that day for Beirut.[9] Accompanied by the Greek ship, Medway was escorted by the light cruiser and the destroyers,,,,,, and . The next day, off Port Said, fired two torpedoes that sank Medway; 30 men were lost in the sinking.[9] [10] 47 of the 90 spare torpedoes aboard floated free of the wreck and were salvaged.[9]
. Henry Trevor Lenton. British & Empire Warships of the Second World War. Naval Institute Press. Annapolis, Maryland. 1998. 1-55750-048-7.