A roll film negative. On board the Tribal class type 81 frigate Mohawk (1962) in Portsmouth Dockyard. She was in a dry dock from 21 March to 11 April 1972 when she moved to the South Railway Jetty. In the hull outfit 18 sonar (type 177) compartment between 32 and 37 stations on 4 deck, looking aft from forward. The sonar dome is lowered. A spare dome cover is on the left and a telephone is on the extreme right.