1929 twin-engine 4-A-1 amphibian. Only three were built, and there is very little information available on them (for instance, at the time of this writing, a Google search came of with a grand total of zero photos of the 4-A-1..he company was established in an old Martin plant in Cleveland, Ohio by president Col. Benjamin Castle. According to
Aerofiles, the prototype, NC851K was powered by a pair of 115-hp Cirrus Hermes inline engines, and was severely underpowered and crashed on takeoff, while be flown by Holden C. Richardson, who was the Navy's first engineering test pilot. His presence suggests that Great Lakes was developing the 4-A-1 with hopes of marketing it to the Navy.
To solve the problem, the next aircraft, NC850K (the subject of our two photos), was equipped with two Wright J-6 Whirlwinds;
Aerofiles describes these as 300-hp engines, but that would make them the 7-cylinder R-760 or 9-cylinder R-975, and these are clearly only five-cylider engines, which would make them R-540s, in the 165-hp to 175-hp range. So either what is shown in our photos is an interim re-engining, or the 300-hp claim is overstated.
The original company was a victim of the Great Depression, like so many other small aircraft manufacturers. While the 4-A-1 amphibian, for what ever reason, was not built in quantity, Great Lakes built 264 Sport Trainers during the short time they were in business, and subsequent companies using the same name have continued to build more.