Further research has lead me to think that when Dad was assigned to HMS Cochrane in October 1942 from the Nelson, whilst alongside in Rosyth, it was not for training or a shore base but a depot ship that was alongside permanently. It seems the HMS Cochrane I was the shore base and HMS Cochrane II was the accounting posting for spare bods. HMS Cochrane was designated as a Base depot ship, or sometimes know as a destroyer depot ship. She started out as the Booth Line passenger ship RMS Ambrose. She was built on the Tyne and delivered in October 1903. Her employment was from Liverpool to South America and especially the Amazon and Manaus. She was built for the rubber boom and carried 149 1st Class and 330 steerage Class. She was 375’ x 48’ x 18’ draft. 4588grt and 2490 nrt and did 12 kts. An interesting story occurred in 1913 in the Mersey shipping channel off Hoylake. A council dump hopper barge BETA had just dumped her cargo of refuse when she collided with a fishing boat called FLEETWING. Beta was just rescuing 4 men from the water when the RMS Ambrose ran into her stern when inbound to Liverpool. If it wasn’t odd enough that there were two collisions like that, one of the twelve who lost their lives was an AB called A. Porter!
She was requisitioned in December 1914 by the Navy and converted into an armed merchant cruiser becoming AMC Ambrose. She joined the 10th Cruiser Squadron whose task it was to guard the northern approaches from the Norwegian coast right out into the Atlantic. She was again converted to a submarine depot ship in 1915. Her Grt increased to 6600t and her compliment was 238. In 1917 she was in Malta and in 1919 she was in Portsmouth. Then in 1927 she was in China as the depot ship for the 4th Submarine Flotilla when the submarine Poseidon was sunk in collision with a Chinese ship and 4 men escaped using escape breathing equipment for the first time. Some sources then say she was later converted again into a depot ship for destroyers. 1932 found her on the reserve list and in 1936 she was not even on that list. She was obviously reprieved and in 1938 she had her name changed to HMS Cochrane and appears to have been the base depot ship at Rosyth throughout the war. She was scrapped in 1946.
HMS Ambrose. Submarine depot ship.
1. Dad’s serial number P/JX 252239. The P means he was from the Portsmouth Division. The J signifies that he was in the seaman or communications branch and the X means that he joined up after a big pay review in the early 1930’s