M2 1918
M3 1920
M2 1929
| Name | No | Builder | Laid down | Launched | Comp | Fate |
| M1 | Vickers, Barrow | 7/1916 | 9/7/1917 | 4/1918 | collision 12/11/1925 | |
| M2 | Vickers, Barrow | 7/1916 | 19/10/1918 | 2/1920 | foundered 26/1/1932 | |
| M3 | Armstrong, Elswick | 12/1916 | 19/10/1918 | 7/1920 | BU 4/1932 | |
| M4 | Armstrong, Elswick | 1916 | 20/7/1919 | --- | cancelled 1918 |
|
Displacement standard, t |
|
|
Displacement normal, t |
1594 - 1633 / 1946 |
|
Length, m |
M1, 2: 90.2 M3: 93.2 |
|
Breadth, m |
7.50 |
|
Draught, m |
M1, 2: 4.90 M3: 4.80 |
|
No of shafts |
2 |
|
Machinery |
2 12-cyl Vickers diesels / 4 electric motors |
|
Power, h. p. |
2400 / 1600 |
|
Max speed, kn |
15 / 9 |
|
Fuel, t |
diesel oil |
|
Armament |
M1, M2: 1 x 1 - 305/40 Mk IX, 1 x 1 - 76/45 QF Mk I HA, 4 - 450 TT (bow, 8) M3, M4: 1 x 1 - 305/40 Mk IX, 1 x 1 - 76/45 QF Mk I HA, 4 - 533 TT (bow, 8) |
|
Complement |
65 |
| Diving depth operational, m | 30 |
Ship project history: Unusual "submarine monitors" armed with 12`` gun similar mounted on Formidable class battleships. They were intended for support of torpedo attacks and coast bombarding. 50 305mm shells were stowed in magazines and could be fired in 30sec from periscope depth. Main machinery was identical to "L" class. Gun trials were appeared very successful, gun had elevate angles -5 - +20° and train 15°. Submarines were completed too late to operate in their original role and conversion of M2-4 to usual patrol submarines without 305mm guns was only vetoed by First Sea Lord.
Modernizations: 7/1927, M3: - 1 x 1 - 305/40; + 100 mines, surfaced displacement rose up to 1745t.
(10/1925 - 4/1928), M2: - 1 x 1 - 30540; + 1 catapult and 1 Parnall Peto seaplane, surface displacement was 1788t.
Naval service: Ì1 12/11/1925 was lost being rammed by s/s Vidar. 26/1/1932 her fate has shared by submarine seaplane carrier M2. Some months later submarine minelayer M3 was sold for BU.
M1 1919
© Ivan Gogin, 2008-10