The Stinson Reliant was a product of the pre-World War 2 (1939-1945) period and used in the liaison and training roles. It carried a shoulder-mounted monoplane form giving it excellent lift, low-altitude handling, and short-field capabilities. 1,327 of the type were produced in a myriad of variants and these went on to serve a large collection of global operators ranging from Argentina and Australia to Paraguay and the United States.
The Stinson Aircraft Company was founded after the fighting of World War 1 (1914-1918) in 1920 and managed an existence until after World War 2 in 1948. Based out of Detroit, Michigan, the company excelled at the lightweight plane concept with many of its creations seen sporting shoulder-mounted wing mainplanes. The company's first major contribution was the SB-1 "Detroiter" - a single-engine cabin biplane - of which twenty-six examples were from 1926 on (ultimately more than 100 aircraft were built under the Detroiter name).
Production of the Reliant occurred in the pre-war years beginning in 1931 and ended when the war was in full swing in 1943. While many early types were conditioned for civilian use, the first dedicated military forms were finally introduced in February of 1942 when the United States war machine required aircraft of all types for the effort. Both the British and the Americans relied on the lightweight aircraft to survey battlefields, conduct reconnaissance runs, communications, and ferrying passengers to and fro. For the latter party, the aircraft was designated as UC-81 and AT-19 marking utility and trainer roles, respectively. Several aircraft mimicking the form and function of the Reliant were utilized by the United States and other military powers of the wartime period.
Variants of the Reliant proved plenty and, therefore, the aircraft could be pressed into a variety of roles including general cargo hauling, air ambulance, photographic scouting, firefighting, and target towing. The civilian market line began with the SR Reliant and this form carried the Lycoming R-680 radial piston engine of 215 horsepower. This was followed by the SR-1 with its Lycoming R-680-2 engine of 240 horsepower - two were built. From this beginning arrived other marks ranging from SR-3 to the SR-10K, the latter powered through a Wright R-760E-3 engine - eleven of this mark were produced in all.
The SR-10F production form carried a crew of one and up to four passengers. Dimensions included a running length of 27.10 feet, a wingspan of 41.6 feet, and a height of 8.5 feet. Empty weight was 3,045lb against a Maximum Take-Off Weight (MTOW) of 4,605lb. Power was from a single Pratt & Whitney "Wasp Junior" SB 9-cylinder, air-cooled radial piston engine developing 400 horsepower and driving a two-bladed propeller unit at the nose. With this configuration, the aircraft could manage a cruising speed near 177 miles-per-hour, a range out to 850 miles, and a service ceiling up to 21,000 feet. Rate-of-climb was 1,330 feet-per-minute.
Military marks began with the AT-19 designated by the United States Army Air Forces (USAAF) and operated by the British Royal Navy through Lend-Lease as the "Reliant I" - 500 examples being produced. Fifty-one AT-19s were converted for the photographic surveying role as the AT-19C. Utility marks began with the UC-81 and ran, in order, to the UC-81N. The L-12 were a pair of SR.5A models taken into USAAF service while the L-12A were a pair of SR-7Bs. RQ-1 was used to designated a one-off SR-5 model taken on by the United States Coast Guard service in 1935 - this example was eventually redesignated as the XR3Q-1 and operated into 1941 by the United States Navy.