HMS Hermes was a British aircraft carrier built for the Royal Navy and was the world's first ship to be designed as an aircraft carrier, although the Imperial Japanese Navy's Hōshō was the first to be launched and commissioned. The ship's construction began during the First World War but not completed until after the end of the war, delayed by multiple changes in her design after she was laid down. After she was launched, the Armstrong Whitworth shipyard which built her closed, and her fitting out was suspended. Most of the changes made were to optimise her design, in light of the results of experiments with operational carriers.
Deep diving is underwater diving to a depth beyond the norm accepted by the associated community. In some cases this is a prescribed limit established by an authority, while in others it is associated with a level of certification or training, and it may vary depending on whether the diving is recreational, technical or commercial. Nitrogen narcosis becomes a hazard below 30 metres (98 ft) and hypoxic breathing gas is required below 60 metres (200 ft) to lessen the risk of oxygen toxicity.
Altitude diving is underwater diving using scuba or surface supplied diving equipment where the surface is 300 metres (980 ft) or more above sea level. Altitude is significant in diving because it affects the decompression requirement for a dive, so that the stop depths and decompression times used for dives at altitude are different from those used for the same dive profile at sea level. The U.S. Navy tables recommend that no alteration be made for dives at altitudes lower than 91 metres (299 ft) and for dives between 91 and 300 meters correction is required for dives deeper than 44 metres (144 ft) of sea water. Most recently manufactured decompression computers can automatically compensate for altitude.
Sheck Exley was an American cave diver. He is widely regarded as one of the pioneers of cave diving, and he wrote two major books on the subject: Basic Cave Diving: A Blueprint for Survival and Caverns Measureless to Man. On February 6, 1974, Exley became the first chairman of the Cave Diving Section of the National Speleological Society. During his career, he established many of the basic safety procedures used in cave and overhead diving today. Exley was also a pioneer of extreme deep scuba diving.
The XE-class submarines were a series of twelve midget submarines that were built for the Royal Navy during 1944; four more to a slightly different design were built 1954-5 as the Stickleback class. They were an improved version of the X class used in the attack on the German battleship Tirpitz.
An atmospheric diving suit (ADS) is a small one-person articulated submersible which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere. The ADS can be used for very deep dives of up to 2,300 feet (700 m) for many hours, and eliminates the majority of significant physiological dangers associated with deep diving; the occupant need not decompress, there is no need for special gas mixtures, nor is there danger of decompression sickness or nitrogen narcosis. Divers do not even need to be skilled swimmers, but the disadvantage is limited dexterity.
HMS L20 was a L-class submarine built for the Royal Navy during World War I. The boat was not completed before the end of the war and was sold for scrap in 1935.
High diving is the act of diving into water from relatively great heights. High diving can be performed as an adventure sport, as a performance stunt, or competitively during sporting events.
David John Shaw was an Australian scuba diver, technical diver, and airline pilot for Cathay Pacific, flying the Lockheed L-1011 Tristar, then the 747-400, and then the A330-300, A340-300, and A340-600. He flew for Cathay Pacific from 1989 until his death in 2005. Before flying for Cathay Pacific he flew for Missionary Aviation Fellowship in Papua New Guinea and Tanzania. He also flew agricultural aircraft in South Australia and New South Wales.
Guo Jingjing is a retired Chinese female diver, and multi-time Olympic gold medalist and world champion. Guo is tied with her partner Wu Minxia for winning the most Olympic medals (6) of any female diver and she won the 3m springboard event at five consecutive World Championships. She announced her retirement in 2011.
Persier was a 5,382 GRT cargo ship which was built in 1918 as War Buffalo for the British Shipping Controller. In 1919, she was sold to Belgium and renamed Persier. Between 1934 and 1941 she also held a passenger certificate. She was driven ashore on the Icelandic coast in a storm in February 1941 which put her out of action for two years. Returned to service in February 1943, she served until 11 February 1945, when she was torpedoed and sunk by U-1017 with the loss of 20 crew.
Deon Dreyer was a South African recreational scuba diver who died in Bushman's Hole in South Africa. Cave diver David Shaw died more than 10 years later whilst attempting to retrieve Dreyer's body.
Empire Clough was a 6,147 GRT cargo ship which was built in 1942 by John Readhead & Sons Ltd of South Shields for the Ministry of War Transport (MoWT). She was torpedoed and sunk on her maiden voyage.
Jarrod Michael Jablonski is a pioneering technical diver and record setting cave diver. Jablonski is one of the main architects behind the 'Doing It Right' system of diving.
Walter L M Russ was a 1,538 GRT cargo ship built in 1927 in Rostock, Germany. In 1945, she was seized by the Allies and passed to the Ministry of War Transport (MoWT). It was intended that she would be renamed Empire Concourse but in July 1945 she ran aground between Wales and Ireland, and was wrecked.
HMS Thracian was an S-class destroyer built for the Royal Navy during the First World War.
The plunge for distance is a diving event that enjoyed its greatest popularity in the 19th and early part of the 20th century, even being included as an official event in the 1904 Summer Olympics. By the 1920s, it began to lose its popularity and slowly disappeared from U.S. and English swim competitions.
Guy "Rusty" Garman, sometimes known as Doc Deep, was a physician and scuba diver who died during an attempt to set a world record recreational deep dive on 15 August 2015, aged 56.
Diamond Reef System, including each individual Hover Station and the new Multi-Portal System, are trademarked, skill evaluation and safety-based diving curriculums that utilize the world's first portable, collapsible underwater obstacle course to simulate fragile reef or dive wreck structure for diver buoyancy skill and underwater photography training. A form of scuba Gymkhana, the program was designed by Pete Wallingford in 1988 to educate scuba instructors and scuba divers on how to safely teach and promote situational awareness, proper body positioning and safe interaction with coral reefs, fragile marine ecosystems and shipwrecks. The program was adopted by the Environmental Protection Agency, the National Oceanic and Atmospheric Administration, dive store operators and dive resort/charter operators worldwide.
The history of underwater diving starts with freediving as a widespread means of hunting and gathering, both for food and other valuable resources such as pearls and coral, By classical Greek and Roman times commercial applications such as sponge diving and marine salvage were established, Military diving also has a long history, going back at least as far as the Peloponnesian War, with recreational and sporting applications being a recent development. Technological development in ambient pressure diving started with stone weights (skandalopetra) for fast descent. In the 16th and 17th centuries diving bells became functionally useful when a renewable supply of air could be provided to the diver at depth, and progressed to surface supplied diving helmets—in effect miniature diving bells covering the diver's head and supplied with compressed air by manually operated pumps—which were improved by attaching a waterproof suit to the helmet and in the early 19th century became the standard diving dress.
