While the submarine has existed for centuries, it was not until World War I that the weapon performed to a level that made it an effective weapon. The German Imperial Navy’s submarine blockade nearly brought Great Britain to her knees and as a result the victorious navies continued the refinement of the submarine as an offensive weapon during the inter-war years. The Royal Navy pushed the envelope of innovation with the creation of the first ever aircraft carrying submarine, HMS M2.
Laid down during World War I, the M2 was originally designed to carry a single 12-in. gun and act as a submersible cruiser. Nearly a decade after her commissioning, the British Admiralty decided to remove the 12-in. gun and use the M2 as a test bed for developing a submarine capable of carrying a small reconnaissance biplane. The tactical concept was that the M2 would screen the battle fleet and use her biplane to extend her effective observational range. To do this, a watertight hangar, crane and launch ramp were added aft of the submarine’s conning tower.
Sadly, the M2 was lost with all hands while conducting exercises on January 26, 1932 in Lyme Bay off Dorset. It is believed the crew opened the hangar door while still submerged thus sinking the ship. A subsequent 11 month salvage attempt failed to bring her and she now lies in 90 feet of water where it has become a popular dive site. The Royal Navy abandoned the aircraft carrying submersible concept shortly thereafter.
The period video below demonstrates the M2 deploying, launching and recovering its single biplane.