Kinner’s bold Envoy design — General Aviation News

By Frederick Johnsen · May 4, 2023 · Leave a Comment

In 1934, Kinner Aircraft of Glendale, California, introduced the Kinner Envoy.

The world economy was still in the grips of the Great Depression, although historians would say recovery started the year before. Nonetheless, offering a then-radical low-wing cabin monoplane seating four was considered by some to be a case of not reading the room, while others would call it inventive, even bold. High-wing cabin monoplanes and cabin biplanes ruled the day.

Historian Joseph Juptner reckoned the Kinner Envoy design was well ahead of the popular curve for low-wing cabin general aviation aircraft, a design style that would not gain mass appeal until after World War II.

Kinner's designer for the Envoy was Max B. Harlow, who three years later went on to create his own niche elegant aluminum low-wing business aircraft that has a loyal following to this day.

Harlow, who would work on Howard Hughes’ radical H-1 racer during the decade, leaned forward to give Kinner a modern cabin design in the Envoy.

The Kinner C-7 Envoy employed thin flying wires bracing the wing, streamlined fillets, a NACA cowling, and wheel pants to diminish drag wherever possible.

The engine was one of Kinner's own, a new seven-cylinder radial called the Kinner C7 (without a dash as used in the aircraft model nomenclature) and rated at 300 horsepower. The Envoy cruised at 150 mph and landed, with flaps, at 46 mph.

Starting at sea level, the Envoy could top 800 feet in the first minute of climbing. Service ceiling was listed at 16,000 feet. Cruising while burning 18 gallons of gas an hour, the Envoy had a range of 700 miles, plenty long for a cross-country leg. Some later Envoys had Kinner engines rated as high as 370 horsepower, with attendant boosts in performance.

The Envoy's fuselage began with a welded steel tube skeleton to which extensive wooden formers gave a rounded, well-faired shape that was fabric covered. Aluminum skin panels adorned the cockpit area.

Originally, the windscreen raked forward to block glare, a style that enjoyed some popularity in the 1930s on aircraft including the Vultee V-1A and early Boeing 247 airliners. By 1936, the Envoy employed a sweptback windscreen.

A single throw-over control wheel served left and right seats in the cockpit. Routed spruce I-beam wing spars supported spruce truss and plywood wing ribs.

Aluminum leading edges capped the wings, which were fabric covered. Stub wings were integral to the fuselage and hosted the landing gear, as well as baggage compartments. Juptner noted the overall baggage weight allowance would be reduced by 20 pounds for each parachute carried.

Juptner's search of records yielded a possible production run of only about seven Kinner Envoys, including three for the U.S. Navy as staff transports in 1936. Their Navy nomenclature, XRK-1, is sometimes seen painted on the rudder.

As delivered, the XRK-1s flew with the Kinner 340-horsepower R-1044-2 engine, but one was converted to use a 400-horsepower Pratt and Whitney R-985-38 radial. A twin-float mounted Kinner C-7 was said to be exported to Japan around 1936 or 1937.

Winfield "Bert" Kinner was the first tenant with a hangar facility at the new Glendale, California, airport in the late 1920s, an airfield that went on to gain aeronautical fame as Grand Central Airport. The aircraft production side of the Kinner concern went bankrupt in 1937. The engine-building portion was reorganized and survived until after World War II.

Bert Kinner, former streetcar driver, taxi operator, and car dealer, had an affinity for internal combustion engines. Many of his air-cooled designs powered airplanes built by other manufacturers.

Grand Central Airport went from being a bustling air terminal and hub for movie scenes and movie stars in the 1930s to a non-airport industrial area surrounding its iconic stucco-and-tile terminal building that survives to this day.