'D' Class

[D1] [D2] [D3] [D4] [D5] [D6] [D7] [D8]

The 'D' Class (D4), was the first class of British submarine to be fitted with a deck gun

'Overseas Submarine'
8 Built

Submarine Builder Built D1 - D6 Vickers, Barrow-in-Furness 1907 - 1912 D7 - D8 HM Dockyard, Chatham 1910 - 1912

 

This Class was the first of the Overseas type design which ultimately became the prototype for the majority of Patrol type submarines. The delay in the production of this type of submarine had been in the main, the difficulty of producing a satisfactory propulsion system. The introduction of the diesel engine to the submarine service, 'D1' being the first submarine to be fitted with a diesel engine.  There was also a revolutionary design to the bow tubes, being placed one above the other in preference to side by side. T his enabled the design of the bows to take a much finer shape.

In reality the introduction of this class was a giant step forward in many aspects. As already stated, the first to be fitted with diesel engines, saddle tanks, twin screws and much improved living conditions for the much larger crew (25) as well as a radio transmitter and receiver. The aerial for the radio was fitted to a mast which had to be lowered before diving.

All of this class were kept in Home waters. During WWI they were intended to operate in the North Sea against German warships. They operated from Dover, Harwich, Immingham and Blyth until 1917-1918 when they were relegated to training duties at Portsmouth. Four of the class were lost, 3 in action and one used as a target.

Whilst researching this particular piece of information I recalled seeing an old newsreel showing a crew member carrying a basket of pigeons onboard. Did these poor souls become fresh meat after the introduction of the radio?

Technical Information

Displacement (tons): 500 sf 620 sm Length (ft): 162 oa Breadth (ft) 20.5 oa Draught/Height (ft): 11.0 Machinery: 1,200 hp Vickers Diesel Engine. 550 hp electric motors. Speed (kts): 14.5 sf 10.0 sm Oil Supply (tons): 35 max Armament: 3 x 18 inch tubes (2 bow, 1 stern) 1 12pdr QF gun D4 and others. Reloads: na Range: 2,500 nm at 10 knts sf 45 nm at 5 kts sm Complement: 3 officers and 22 ratings.

sm = submerged, sf = surfaced,
oa = overall, hp = horsepower, na = not available