HMS A1

-		Career	Royal Navy Ensign
Ordered:
Laid down:
Launched:	July 9 1902
Commissioned:
Decommissioned:
Fate:	Lost 1911. Wreck rediscovered 1989.
Struck:
General Characteristics
Displacement:	190 tons surfaced207 tons submerged
Length:	103.25 feet (31 m)
Beam:	11.9 feet (3.6 m)
Draught:
Propulsion:	16 cylinder Wolseley 450 hp (336 kW) gasoline engine, 87 horsepower (65 kW) electric motor
Speed:	maximum 11.5 knots (21 km/h) surfaced,maximum 7 knots (13 km/h) dived
Range:	500 nautical miles (926 km) at 11.5 knots (21 km/h) surfaced20 nautical miles (37 km) submerged at 5 knots (9 km/h)
Complement:	11 (2 officers and 9 ratings)
Armament:	One 18 inch (457 mm) torpedo tube, plus two reloads

HMS A1 was the Royal Navy's first British-designed submarine, and their first to suffer fatal casualties.

She was the lead ship of the first British A-class of submarines (a second, much different A (for Amphion) class submarine appeared towards the end of the Second World War), and the only one to have a single bow torpedo tube. She was an enlarged and improved Holland boat - 40 feet (12.2 m) longer than the Royal Navy's five Holland boats. The most notable improvement was the addition of a conning tower. Subsequent A class boats were even larger and differed from her in several respects.

Like all members of her class, she was built at Vickers, Barrow-in-Furness. She was launched on July 9 1902.

She was accidentally sunk in the Solent on March 18 1904 whilst carrying out a practice attack on HMS Juno by being struck on the starboard side of the conning tower by a mail steamer, SS Berwick Castle which was en route from Southampton to Hamburg. She sank in only 39 feet (12 m) of water but the boat flooded and the entire crew were drowned. One consequence was that all subsequent Royal Navy submarines were equipped with a watertight hatch at the bottom of the conning tower.

She was raised on April 18 1904 and repaired and re-entered service. Following a petrol explosion in August 1910, she was converted to a testbed for the Admiralty's Anti-Submarine Committee. She was lost a year later when running submerged but unmanned under automatic pilot. The wreck was discovered in 1989 at Bracklesham Bay. It was designated under the Protection of Wrecks Act on 26 November 1998.