01/31/2009. Remarks by Johan Visschedijk: "Percival "Spence" Hopkins Spencer (April 30, 1897 – January 16, 1995) made his first solo flight in a glider on April 2, 1911 and first solo flight in a powered aircraft on May 15, 1914. When he stopped piloting in February 1988, after more than 6500 hours of flying in his logs, he had been flying for more years than any other person, and was believed to be the oldest licensed pilot in the United States.

Spencer became known for the design of several single-engined amphibians, dating back to the Privateer of 1930, produced by Amphibians Inc. of Garden City, Long Island, New York, followed by the Spencer-Larsen SL-12C, Spencer S-12 Amphibian Air Car, Republic RC-1 Thunderbolt Amphibian, RC-2 Seabee and RC-3 Seabee, and the Trident TR-1 Trigull. All of these designs were variations of Spencer's basic Air Car configuration, on which he was granted a patent on January 3, 1950.

The S-12 was originally an 110 hp powered two-seater, in 1968 it was developed into an 180 hp Lycoming O-360 powered four-seater, known as the S-12C. Built by Spencer and retired USAF Colonel Dale "Andy" L. Anderson, the prototype N111DA (owned by Anderson) first flew on May 25, 1970. Spencer then completed the 260 hp Lycoming O-540 powered S-12D, of which plans became available to homebuilders as well as certain glass fiber moldings and metal assemblies.

Continued development led to the S-12E, N111DA became prototype, re-engined with a 285 hp Teledyne Continental Tiara 6-285-B. The first S-12E to be completed from Spencer's plans was the pictured N6PB built by Peter Breinig of Sausalito, California, that was first flown on August 1, 1974. Nearly 35 years later the aircraft is still registered to Peter Breinig."