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 Trieste II | |
| History | |
|---|---|
 United States | |
| Name | Trieste II |
| Builder | Mare Island Naval Shipyard |
| Completed | 1964 |
| In service | 1 September 1969 |
| Out of service | 1980 |
| Reclassified |
|
| Fate | Preserved at theNaval Undersea Museum |
| General characteristics | |
| Type | Deep-submergence vehicle |
| Displacement | 46long tons (47 t) |
| Length | 67 ft (20 m) |
| Beam | 15 ft (4.6 m) |
| Draft | 12 ft 5 in (3.78 m) |
| Test depth | 20,000 ft (6,100 m) |
| Complement | 2 |
Trieste II(DSV-1) is theUnited States Navy's firstbathyscaphe purchased from its Swiss designers, and the successor toTrieste.
The originalTrieste design was heavily modified by theNaval Electronics Laboratory inSan Diego, California and built at theMare Island Naval Shipyard.Trieste II incorporated the originalTerni, Italian-built sphere used inTrieste, after it was made redundant by the new high-pressure sphere cast by the GermanKrupp Steelworks. TheTrieste sphere was suspended from an entirely new float, more seaworthy and streamlined than the original, but operating on identical principles. Completed in early 1964,Trieste II was placed on boardUSNSFrancis X. McGraw (T-AK241) and shipped, via the Panama Canal, to Boston.[1]
Commanded by Lt Comdr. John B. Mooney Jr., with co-pilot Lt. John H. Howland and Capt. Frank Andrews,Trieste II conducted dives in the vicinity of the loss site ofThresher – operations commenced by the firstTrieste the year before. She recovered bits of wreckage, positively fixing the remains as that of the lostThresher, in September 1964.
Between September 1965 and May 1966,Trieste II again underwent extensive modification and conversion at Mare Island Naval Shipyard, but there is no clear record that she was ever operated in that new configuration, i.e., the addition ofskegs or outriggers on both sides of the sphere.[2]
During that same time period, work was under way on a third configuration of the bathyscaphe. This work resulted in yet a new appearance for theTrieste II, and included the installation of a new pressure sphere, designed for operation to 20,000 feet (6,100 m).
As the bathyscaphe continued her operations as a test vehicle for the deep submergence program, she qualified four officers as "hydronauts" – the beginning of a burgeoning oceanographic operation.Trieste II's valuable experience in deep submergence operations has helped in the design and construction of other deep-diving submersibles which could be used in rescuing crews and recovering objects from submarines in distress below levels reachable by conventional methods.
This unique craft was listed only as "equipment" in the Navy inventory until the autumn of 1969. On 1 September 1969,Trieste II was placed in service, with the hull number X-1. She was reclassified as a deep submergence vehicle (DSV) on 1 June 1971.
On 25 April 1972,Trieste II recovered a satellite package called a "bucket" weighing several hundred pounds from a depth of greater than 16,000 feet (4,900 m), a record at the time.[3]Trieste II (DSV-1) continued her active service in the Pacific Fleet into 1980.
TheTrieste class DSV were replaced by theAlvin class DSV, as exemplified by the famousAlvin (DSV-2). TheAlvins are more capable, more maneuverable, less fragile, but also can not dive as deep, reaching only a maximum of 20,000 feet (6,100 m) (for theSea Cliff (DSV-4)).[citation needed]
Trieste II is now preserved as amuseum ship at theNaval Undersea Museum,Keyport, Washington.
47°42′01″N122°37′26″W / 47.70024°N 122.62381°W /47.70024; -122.62381
