Between 1955 and 1960, A boats were modernized on the same lines as the T Class, with a complete rebuilding of the forward and after hull sections, lengthening and streamlining. The two external torpedo tubes forward and aft were also removed, leaving a total of six.
From 1967 on, these fine submarines were progressively scrapped. In 1972, HMS Aeneas was hired by Vickers for successful trials of SLAM (Submarine-Launched Anti-aircraft Missile) - a four-barrel cluster of guided missiles on a launcher mounted in the fin, having high lethality against low-flying aircraft.
As the Barrow-built HMS Andrew awaited disposal in 1977, the end of an era was signalled - she was the oldest submarine in
