HMS A1

HMS A1 is a British submarine that rests on the seafloor near the coast of Sussex. The wreck sits in relatively shallow water and is legally protected to preserve its historical significance.

The submarine was the first designed and built entirely in Britain and launched in 1902. It sank just two years later after colliding with a passenger vessel during a training exercise near Bracklesham Bay.

This submarine wreck demonstrates early 20th-century British naval engineering and represents a milestone in the development of underwater military vessels.

The site is protected under the Protection of Wrecks Act and visits require special permits. Divers should check with authorities beforehand and only work with authorized dive teams.

The submarine was powered by an unusual combination of a petrol engine at the surface and electric batteries when submerged. This hybrid approach was typical of early British submarines and reflects the experimental nature of the technology at that time.