Undine 1939
| Name | No | Builder | Yard No | Laid down | Launched | Comp | Fate |
| Undine | C48 | Vickers-Armstrong, Barrow | 2/1937 | 5.10.1937 | 8/1938 | sunk 7.1.1940 | |
| Unity | C66 | Vickers-Armstrong, Barrow | 2/1937 | 16.2.1938 | 12.1938 | collision 29.4.1940 | |
| Ursula | C65 - N65, 2.1949- S... | Vickers-Armstrong, Barrow | 2.1937 | 16.2.1938 | 12.1938 | to Soviet Union 5.1944 - 2.1949 (Â-4) (V-4), BU 5.1950 |
|
Displacement standard, t |
540 |
|
Displacement normal, t |
630 / 730 |
|
Length, m |
58.2 |
|
Breadth, m |
4.90 |
|
Draught, m |
4.62 |
|
No of shafts |
2 |
|
Machinery |
2 Paxman-Ricardo diesel-generators, 2 electric motors |
|
Power, h. p. |
615 / 825 |
|
Max speed, kn |
11.25 / 10 |
|
Fuel, t |
diesel oil 38 |
|
Endurance, nm(kts) |
4050(10) / |
|
Armament |
3 x 1 - 12.7/62, 6 - 533 TT (4 bow, 2 ext bow, 10) Ursula: 1 x 1 - 76/45 20cwt QF Mk II, 3 x 1 - 12.7/62, 6 - 533 TT (4 bow, 2 ext bow, 8) |
| Sensors | type 129 sonar |
|
Complement |
27 |
| Diving depth operational, m | 60 |
Project history: These submarines were originally designed as unarmed targets for ASW training. Already after design approval it was decided to arm them with torpedoes. Fore end was redesigned for placing 4 TTs in the pressure hull and two more out of it, in a special fin. Single-hulled. Feature of this class that only electric motors were coupled with shafts and diesels used only in a role of generators. There were first British pure diesel-electric submarines.
New boats received a designation as "U" class, have appeared very successful, and better than boats of other classes suited for actions in Mediterranean and Northern Seas, however originally a class have limited to three units of the 1936 Programme.
Modernizations: about 1942 - 1943, Ursula: can carry 6 M2 mines instead of torpedoes, + type 286W or type 291W radar
2/1949, Ursula: 1 x 1 - 76/45 CP Mk V, 6 - 533 TT, type 286W or type 291W radar, type 129 sonar
Naval service: Undine was sunk 7.1.1940 in North Sea by DCs of German minesweepers Ì1201, Ì1204 and Ì1207. Unity was lost 29.4.1940 in collision with s/s Atle Jarl in the North Sea.
Ursula 1940
© Ivan Gogin, 2008-13