SONAR/ASDIC branch
 

Sonar/ASDIC branch:

Sonar & Radar played a big part in the winning of the critical Battle of the Atlantic. Much of the development of both branches took place both in UK & USA during WWII, especially later in the war.

ASDIC – in 1939 the Admiralty made up the story that the letters stood for 'Allied Submarine Detection Investigation Committee', and this is still widely believed, though no committee bearing this name has ever been found in the Admiralty.

Sonar - acronym for sound navigation and ranging, was the US term for ASDIC & was adopted by the RCN as well.

At least four former RCN WWII veterans, who were Sonarmen, have related to me that in order to keep the advancements & developments made to Sonar during the war, the courses they had to undergo to learn about Sonar were very secret & they were not permitted to communicate to others what it was they were learning. Also they were not permitted to wear their Sonar rate badges when serving on ships escorting convoys over the Atlantic or into the Africa/Mediterranean theatre. This was in case their ship was sunk & they might be captured & forced to reveal what they knew about Sonar. Instead they wore another rate badge so they would not be identified as Sonar ratings.

Sonarmen received their distinguishing rate badges in 1930, many of them having first served in the Torpedo branch.
The WWII period Sonar rate badges are illustrated below. These rate badges survived until the formation of the RCN TAS branch in 1949.


Bryan