In 1975, after
conducting deep ocean surveys since 1958, USNS Michelson was
declared unfit for sea and taken out of service. The reasons
for this are obscure but it's likely the ship failed a Coast
Guard inspection of the hull. The ship's mechanical systems could be
repaired or replaced but the hull's integrity was another matter.
Michelson had experienced cracks in the deck plating during the
mid-1960s.
A replacement for the ship was found but not placed into service until
1978. The new home for Oceanographic Unit Three was the C4-S-1sa vessel
originally SS Canada Mail, renamed USNS H. H. Hess (T-AGS-38), named
for geologist Harry Hammond Hess.
Launched in 1964, SS Canada Mail was longer, faster and had a deeper
draft than the VC2-S-AP3 Victory vessels that became survey ships
Bowditch, Dutton and Michelson. It also carried up to 12
passengers on voyages from Pacific Northwest ports to
East Asia.
A "break bulk" vessel, SS Canada Mail had a short useful
life, overtaken by the containerization of ocean freight. By
1974 it was in the "reserve fleet" at Suisun Bay in California.
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| SS Canada Mail as operated by American Mail Lines. Note the unusual A-frame masts. |
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| A sales brochure for American Mail Line passenger service. |
Oceanographic Unit Three, previously aboard USNS Michelson, was transferred to H. H. Hess. Alterations resulting from the conversion were largely internal and below the waterline. Outwardly, the vessel appeared little changed. Michelson's electronics including the SASS array sonar were installed aboard the ship. The first surveys were conducted in the Pacific in June 1978.
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| USNS H. H. Hess at sea in a postcard photo: 563 feet long, 76 foot beam, 27 foot draft, 19,250 hp steam turbine powered, 20 knots. |
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| A starboard side view of H. H. Hess, probably at Port Canaveral. |
More about H. H. Hess including ship's movements, crew lists, documents, ship's newspapers and additional photos can be found here.
