The Spartan NP-1 was a two-seat primary trainer developed by the Spartan Aircraft Company in Tulsa, Oklahoma. The aircraft emerged from the NS-1 prototype, which was designed in 1939 by engineers Lloyd Pearce and Fred Stewart. The prototype first took flight in Tulsa on September 23, 1939. The design was an evolution of the earlier Spartan C3 biplane, modified specifically for military utility. These modifications included a narrower fuselage, an increase in wingspan by 18 inches, and the addition of replaceable aluminum wingtips.
Technically, the NP-1 featured a wood-and-fabric wing paired with a steel-tube fuselage covered in fabric. It was powered by a Lycoming R-680 radial piston engine, specifically the R-680-B4C model, which produced 225 hp. While the aviation industry was shifting toward monoplane trainers at the time, the U.S. Navy adopted the NP-1 because of the urgent need for a simple, effective primary trainer during the early stages of World War II.
Production took place at Spartan's facility located on North Sheridan Road and Sheridan Avenue near the Tulsa Municipal Airport. The U.S. Navy awarded a contract for 200 aircraft on July 5, 1940, with construction beginning in August 1940. By December 7, 1941, approximately half of the contracted aircraft had been delivered. Production concluded in mid-1942, resulting in a total of 202 aircraft: one prototype, 200 production units, and a single example known as the “Spirit of Spartan.”
In military service, the NP-1 operated across various Naval Air Stations, including those in Dallas, Atlanta, New Orleans, Kansas City, Olathe, and Glenview, as well as Grosse Isle and the Minneapolis Naval Air Station at Wold-Chamberlain Field. There is no evidence that the NP-1 saw civil or commercial service, and it was not utilized at Spartan's own flight schools in Oklahoma. The prototype remained with the manufacturer throughout the war as a training aid before being scrapped in the late 1940s. The NP-1 represents the final major complete-aircraft military program for the Spartan Aircraft Company, which eventually ceased all operations in 1961 after transitioning into trailer manufacturing.