Trieste II (Bathyscaphe)

Trieste II was a deep-diving research submersible of the bathyscaphe type. It was acquired by the United States Navy from Auguste Piccard in 1958 to replace the original Trieste after it was transferred to the Smithsonian Institution. The Trieste II was significantly modified from the original design and incorporated components salvaged from the damaged bathyscaphe Archimède.

Its most significant operational accomplishment was the participation in the search for and recovery of a hydrogen bomb lost off the coast of Palomares, Spain, in 1966. Trieste II used a mechanical arm to grapple and retrieve the weapon from a depth of approximately 2,850 feet.

Following its service in the Palomares operation, Trieste II continued to be used for deep-sea research and exploration. It possessed a pressure hull capable of withstanding the immense pressures of the ocean depths, allowing scientists and engineers to conduct observations and experiments in previously inaccessible environments. The Trieste II also served as a test platform for new deep-sea technologies.

Trieste II was eventually decommissioned and is now on display at the Naval Undersea Museum in Keyport, Washington. Its legacy lies in its contributions to deep-sea exploration, particularly its role in the recovery of the lost hydrogen bomb, showcasing the capabilities of manned submersibles in challenging underwater environments.