Scrapped 1945
Oberon was the first submarine to carry ASDIC - a device originally designed under the auspices of the Allied Submarine Detection Investigation Committee to detect submarines. However, ASDIC, the forerunner of SONAR, was put to good use by submariners against surface targets and took over from the hydrophone which was unable to measure, with any accuracy, the speed, course or distance of an enemy vessel.
