The Thunderbolt was originally built as the U.S. Army mine planter Major General Wallace F. Randolph in 1942/1943 by Marietta Manufacturing of Point Pleasant, West Virginia.  She was a Comanche-Class Auxiliary Minelayer with a length of 188.2 feet, a beam of 37 feet, and she displaced 1,300 gross tons.

Transferred to the custody of U.S. Navy in 1951, she was designated as an auxiliary mine layer ACM-15, however, she was never commissioned into the U.S. Navy. She was berthed at Charleston, South Carolina as a unit of the Atlantic Reserve Fleet. In February 1955, she was re-designated MMA-15, and re-named the Nausett (or Nauset). She was later moved to Green Cove Springs, Florida, where she remained in reserve until struck from the Navy Register in July 1960. She was stripped and sold in May 1961 to Caribbean Enterprises, Inc., Miami.  She was subsequently renamed the Sea Searcher, and served as an oilfield exploration ship.

The research vessel Thunderbolt got her final name by serving as a stationary focal point for lightning strikes. Researchers from Florida Power and Light (FP&L) used 2 jet engines to blast ionized gas into the upper atmosphere, attracting large numbers of strikes on the target vessel. Following the lightning research (in the early 1980s), she was to begin a new career as an underwater surveyor vessel. Unfortunately for the Thunderbolt, she sank at the dock in Miami Harbor. Members of the Middle Keys diving community bought her in 1986 and paid to have her cleaned and prepped as an artificial reef. She was scuttled in 120′ of water off Marathon on March 3, 1986.

Note: The mooring buoys for the Thunderbolt are 15 to 20 below the surface of the water. You have to free dive down to a buoy with a line to tie off. Also, currents can sometimes be significant on the Thunderbolt depending on where the Gulf Stream is. Plan accordingly!

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Lat: 24 39.663 N

Long: 80 57.784 W

Depth of wreck

120 feet

Size of wreck

Length: 188 feet

Beam: 37 feet