Trieste is a Swiss-designed, Italian-built deep-diving research bathyscaphe. In 1960, it became the first crewed vessel to reach the bottom of Challenger Deep in the Mariana Trench, the deepest point in Earth's seabed. The mission was the final goal for Project Nekton, a series of dives conducted by the United States Navy in the Pacific Ocean near Guam. The vessel was piloted by Swiss oceanographer Jacques Piccard and US Navy lieutenant Don Walsh. They reached a depth of about 10,916 metres (35,814 ft).
The timeline of underwater diving technology is a chronological list of notable events in the history of the development of underwater diving equipment. With the partial exception of breath-hold diving, the development of underwater diving capacity, scope, and popularity, has been closely linked to available technology, and the physiological constraints of the underwater environment.
Auguste Antoine Piccard was a Swiss physicist, inventor and explorer known for his record-breaking hydrogen balloon flights, with which he studied the Earth's upper atmosphere. Piccard was also known for his invention of the first bathyscaphe, FNRS-2, with which he made a number of unmanned dives in 1948 to explore the ocean's depths.
A bathyscaphe is a free-diving, self-propelled deep-sea submersible, consisting of a crew cabin similar to a Bathysphere, but suspended below a float rather than from a surface cable, as in the classic Bathysphere design.
Don Walsh is an American oceanographer, explorer and marine policy specialist. He and Jacques Piccard were aboard the bathyscaphe Trieste when it made a record maximum descent into the Challenger Deep on January 23, 1960, the deepest point of the world's oceans. The depth was measured at 35,813 feet (10,916 m), but later and more accurate measurements have measured it at 35,798 feet (10,911 m).
Jacques Piccard was a Swiss oceanographer and engineer, known for having developed underwater submarines for studying ocean currents. In the Challenger Deep, he and Lieutenant Don Walsh of the United States Navy were the first people to explore the deepest known part of the world's ocean, and the deepest known location on the surface of Earth's crust, the Mariana Trench, located in the western North Pacific Ocean.
A deep-submergence vehicle (DSV) is a deep-diving crewed submersible that is self-propelled. Several navies operate vehicles that can be accurately described as DSVs. DSVs are commonly divided into two types: research DSVs, which are used for exploration and surveying, and DSRVs, which are intended to be used for rescuing the crew of a sunken navy submarine, clandestine (espionage) missions, or both. DSRVs are equipped with docking chambers to allow personnel ingress and egress via a manhole.
Kaikō was a remotely operated underwater vehicle (ROV) built by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for exploration of the deep sea. Kaikō was the second of only five vessels ever to reach the bottom of the Challenger Deep, as of 2019. Between 1995 and 2003, this 10.6 ton unmanned submersible conducted more than 250 dives, collecting 350 biological species, some of which could prove to be useful in medical and industrial applications. On 29 May 2003, Kaikō was lost at sea off the coast of Shikoku Island during Typhoon Chan-Hom, when a secondary cable connecting it to its launcher at the ocean surface broke.
Trieste II(DSV-1) was the successor to Trieste – the United States Navy's first bathyscaphe purchased from its Swiss designers.
Frédéric Dumas was a French writer. He was part of a team of three, with Jacques-Yves Cousteau and Philippe Tailliez, who had a passion for diving, and developed the diving regulator with the aid of the engineer Émile Gagnan. Dumas participated with Cousteau in the discovery of deep sea reliefs and flora and fauna of deep sea life and in bringing it to the attention of the general public.
Turtle (DSV-3) was a 16-ton, crewed deep-ocean research submersible owned by the United States Navy. It is sister to Alvin (DSV-2) and Sea Cliff (DSV-4).
DSV-4 is a 25-ton, crewed deep-ocean research submersible owned by the United States Navy, now known only by its hull number, not by its former name.
The FNRS-2 was the first bathyscaphe. It was created by Auguste Piccard. Work started in 1937 but was interrupted by World War II. The deep-diving submarine was finished in 1948. The bathyscaphe was named after the Belgian Fonds National de la Recherche Scientifique (FNRS), the funding organization for the venture. FNRS also funded the FNRS-1 which was a balloon that set a world altitude record, also built by Piccard. The FNRS-2 set world diving records, besting those of the bathyspheres, as no unwieldy cable was required for diving. It was in turn bested by a more refined version of itself, the bathyscaphe Trieste.
Deep-sea exploration is the investigation of physical, chemical, and biological conditions on the ocean waters and sea bed beyond the continental shelf, for scientific or commercial purposes. Deep-sea exploration is an aspect of underwater exploration and is considered a relatively recent human activity compared to the other areas of geophysical research, as the deeper depths of the sea have been investigated only during comparatively recent years. The ocean depths still remain a largely unexplored part of the Earth, and form a relatively undiscovered domain.
Philippe Tailliez was a friend and colleague of Jacques Cousteau. He was an underwater pioneer, who had been diving since the 1930s.
Project Nekton was the codename for a series of very shallow test dives and also deep-submergence operations in the Pacific Ocean near Guam that ended with the United States Navy-owned research bathyscaphe Trieste entering the Challenger Deep, the deepest surveyed point in the world's oceans.
The bathyscaphe Archimède is a deep diving research submersible of the French Navy. It used 42,000 US gallons (160,000 L) of hexane as the gasoline buoyancy of its float. It was designed by Pierre Willm and Georges Houot. In 1964, Archimède descended into "what was then thought to be the deepest part of the Puerto Rico Trench", which the NY Times reported as 27,500 feet (8,400 m).
The Shinkai (しんかい) is a crewed research submersible that can dive up to a depth of 600 m. It was completed in 1970, and until 1981 it had the greatest depth range of any crewed research vehicle in Japan. The Shinkai is owned and run by the Japan Coast Guard and it is launched from the support vessel Otomemaru (乙女丸).
Jiaolong is a Chinese crewed deep-sea research submersible that can dive to a depth of over 7,000 metres (23,000 ft), developed from the Sea Pole-class bathyscaphe. It has the second-greatest depth range of any crewed research vehicle of the Chinese Navy; the only crewed expeditions to have gone deeper were the dives of the Trieste bathyscaphe in 1960, Archimède in 1962, Deepsea Challenger in 2012, and DSV Limiting Factor in 2019.
Georges Houot was a French naval officer and commander of a bathyscaphe unit.
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