Connecticut divers have discovered the wreckage of an experimental submarine built in 1907 and later scuttled in Long Island Sound.

The Defender was found Sunday by a team led by Richard Simon, a commercial diver from Coventry, Connecticut. The submarine was discovered at a depth of over 150 feet (45 meters) off the coast of Old Saybrook, CT.

The 92-foot-long submarine, originally named Lake, was designed and owned by Simon Lake to compete for a US Navy contract. Lake lost that competition and then tried refitting the submarine for minesweeping, salvage, and rescue work, renaming it the Defender. But he never found a buyer. It was a well-known sub and was even visited by aviator Amelia Earhart in 1929.

The submarine spent many years unused, docked in New London before eventually being abandoned on a mud flat near Old Saybrook. It was scuttled by the U.S. Army Corps of Engineers in 1946, but the corps never disclosed where.

AP quotes Richard Simon saying that it was clear when his team found the wreckage that it was indeed the Defender. The length, the size and shape of protrusions on the submarine’s distinct keel, and the shape and location of diving planes characteristic of Lake-built vessels, all helped identify it, he said.

Simon Lake was an American mechanical engineer and naval architect who obtained over two hundred patents for advances in naval design and competed with John Philip Holland to build the first submarines for the United States Navy. He also designed submarines for the navies of Austro-Hungary, Germany, and Russia. 

In 1912, he founded the Lake Torpedo Boat Company in Bridgeport, Connecticut, which built 26 submarines for the United States Navy during and after World War I. Lake’s first submarine for the U.S. Navy, USS G-1 (SS-19½), set a depth record of 256 feet (78 meters) in November 1912.

Historic submarine found in Long Island Sound