Asdic was the British version of sonar developed at the end of World War I based on the work of French physicist Paul Langevin and Russian engineer M. Constantin Chilowsky. The system was developed as a means to detect and locate submarines by their reflection of sound waves. By the start of World War II in 1939, most British destroyers and smaller vessels were fitted with it in a variety of different sets.
| Name | Date of Introduction | Dome | Notes |
|---|---|---|---|
| Type 112 | 1920 | Fitted to some V and W-class destroyers and small escorts like P and PC-class sloops | |
| Type 119 | 1930 | B-class destroyers | |
| Type 121 | Tested 1931 in Woolston | First production retractable dome | Fitted in D, E, F, and G-class destroyers, some cruisers and the sloop Enchantress |
| Type 122 | Detachable | Designed for trawlers and other auxiliaries with a turbo alternator | |
| Type 123 | 1934 | Detachable | Replaced Type 122, designed for ships with a high-frequency motor alternator |
| Type 124 | 1934 | Retractable | C, H, I, J, K, and Tribal-class destroyers, some sloops and older destroyers. First system with a range recorder |
| Type 127 | 1937 | As per Type 122 | Designed for sloops, but widely fitted in frigates and older destroyers. Electronics as per Type 123 |
| Type 128 | Tested 1937 in Acheron | Retractable | A, L, and Hunt-class destroyers |
| Type 141 | ? | No dome, but some modified with British dome as Type 141A | American QCJ/QCL system in Lend-Lease Town-class destroyers, modified with British range and bearing recorders |
| Type 144 | Trials in Kingfisher in 1941 | Retractable | First set specifically intended for ahead-throwing weapons like Hedgehog |
| Type 145 | 1942? | Detachable | Like Type 144, but intended for slower escorts |
| Type 147 | Sea trials aboard Ambuscade, May 1943 | ? | The 147 set with its beamforming 'sword' transducer produced a horizontal 'fan' beam that could give a depth estimate.[1][2] This, as well as the Q attachment, improved targeting for directable weapons, like the new Squid, that were capable of making use of this information. |
| Q attachment | 1943 | NA | Depth-measuring set with 3° horizontal beam, modification to existing Type 144 systems |
Notes
edit- ^ Proc, Jerry (2019). "ASDIC/Sonar Equipment Types - Section B".
- ^ Proc, Jerry (2019). "144 and 147 ASDIC beam shapes".
Bibliography
edit- Brown, David K. (2007). Atlantic Escorts: Ships, Weapons & Tactics in World War II. Annapolis, Maryland: Naval Institute Press. ISBN 978-1-59114-012-2.