The Bathyscaphe Trieste

Auguste Piccard's interests shifted when he realized that a modification of some of his atmospheric balloon concepts would allow descent into the deep ocean. By 1937, he had designed a small steel gondola to withstand great external pressure. Construction began, but was interrupted by the outbreak of war.

Resuming work in 1945, he completed the steel gondola for personnel and a large float was attached for buoyancy, using gasoline as the medium. To make the now floating craft sink, tons of iron were attached to the float with a release mechanism.

The design of the first bathyscaph, FNRS-2 (the original FNRS was Piccard's stratospheric balloon), was relatively straightforward. The passenger compartment was a steel sphere large enough to hold two crew and fitted with two portholes. This sphere was attached to an elongated float filled with gasoline, which is lighter than water and therefore more buoyant. (The relationship of gasoline and water is comparable to that of helium and air, and the bathyscaph has been compared to an underwater balloon.) The tank also had provisions for water and iron ballast, which could be jettisoned at the bottom of the dive in preparation for the ascent.

On November 3, 1948, FNRS-2 made an unmanned trial descent to a record depth of 1.371 meters (4,500 feet) off Dakar, Senegal. Funding difficulties led to the bathyscaph's transfer to the French Navy, and it was officially renamed FNRS-3.

The word bathyscaph was coined by Auguste Piccard from the Greek words BATHOS "deep", and SCAPHOS "ship", thus "Bathyscaph".

This term is properly applied only to those deep submergence vehicles which use a gasoline-filled-float to carry the pressure sphere in which the operators ride.

In 1952 Professor Piccard began construction of the next bathyscaph with the financial and technical support of many institutions, companies and individuals in Trieste, Italy. The bathyscaph was launched on August 1, 1953 and christened "TRIESTE". She was constructed with a pressure sphere manufactured by "Societie Terni" which was designed to operate to a depth of 20,000 feet.

The Trieste basically consisted of a float filled with gasoline and a separate pressure sphere. This sphere provided just enough room for two persons and was built by the Krupp Steel Works of Essen, Germany. To withstand the staggering pressure of 9 tons per square inch (124 MPa) at the bottom of Challenger Deep, the new sphere's walls were 5 inches (127 mm) thick. It weighed 13 tons in air, 8 tonsin water.

From 1953 through October 1957 the "BATISCAFO TRIESTE", as it was known in Italy, conducted 48 dives, to depths exceeding 12,000 feet and did not go unnoticed by the Italian Press, the general public or those wishing to commemorate her existance and accomplishments. Neither did those accomplishments go unnoticed by the United States Navy.

During 1957, TRIESTE was evaluated by the U.S. Office of Naval Research, subsequently purchased, and assigned to the Naval Electronics Laboratory, San Diego, California, where she arrived in December 1958. Here she was extensively modified.

Its primary mission of TRIESTE was to assist and support the oceanographic research efforts of the United States Navy.

Many test programs and scientific projects involving ten dives, were conducted by TRIESTE during the next few years.

Most significant of these was "PROJECT NEKTON" in which TRIESTE conducted a series of seven dives including three deep dives, climaxing on January 23, 1960 in a 35,800 foot descent into the "Challenger Deep". She reached the ocean floor in the Challenger Deep, carrying Jacques Piccard and Lieutenant Don Walsh, USN.

This was the first time a ship, manned or unmanned, had reached the deepest point in the sea. The descent took almost five hours and the two men spent barely twenty minutes on the ocean floor before undertaking the 3 hour 15 minute ascent. They observed small soles and flounders and noted the floor consisted of diatomaceous ooze while on the bottom. The record set that day stands alone today. For this series of dives, TRIESTE was fitted with a new pressure sphere, manufactured by the "Krupp Werke (works)" of Germany and designed for operation to 36,000 feet.

 

That dive gained, not only a record which cannot be exceeded but, world wide recognition of the TRIESTE and its occupants on that dive, Jacques Piccard, son of Auguste Piccard and Navy lieutenant Don Walsh.

Seven miles down; the story of the bathyscaph Trieste
by Jacques Piccard; Robert S Dietz