LeBlond Aircraft Engine Corporation

History

In 1928 Richard K. LeBlond purchased Detroit Aircraft Engineering Corporation, then a subsidiary of Detroit's automaker Rickenbacker owned by World War I pilot and ace Eddie Rickenbacker and the engineer, Glenn D. Angle. and their 5-cylinder Air Cat engine. LeBlond employed the company's designer and previous co-owner, Glenn D. Angle, to improve the design for further production and development. The LeBlond line was continually refined and improved through late 1937.

In December 1937, in order to offset a large tax liability incurred by the LeBlond Tool company, the subsidiary, LeBlond Engines, was sold at a significant loss to Raymond A. Rearwin of Rearwin Airplanes. The purchase was a perfect fit for Rearwin as his company was one of the largest users of LeBlond engines and gave Rearwin a well accepted radial engine to use on his designs. Rearwin renamed the company Ken-Royce Motors after his two sons Ken and Royce Rearwin and continued production of the line until World War Two.

Production of the LeBlond designs never resumed, as the design was not economical compared to the newer "flat" (horizontally opposed) engines of the post-war era. LeBlond/Ken-Royce engine parts were provided during the 1950s by Air Associates and in the 1960s the remaining parts were sold to the Antique Airplane Association of Blakesburg, Iowa.

Products

The LeBlond 5D was the first engine introduced by LeBlond in 1928. The 5D engine design was in essence, a 1925 Detroit Air Cat with minor improvements.

LeBlond 5 Variants

LeBlond 60-5D

Introduced in 1928, the 60-5D was a 60 hp (45 kw) 5-cylinder, air-cooled, radial piston engine with a displacement of 234 cubic inches (3.8 litres). This model used iron cylinder heads and was a direct development of the Detroit Air Cat.

LeBlond 70-5DE

Introduced in 1930, the 70-5F was a 70 hp (52 kw) 5-cylinder, air-cooled, radial piston engine using iron cylinder heads and two bearings.

LeBlond 85-5DF

Introduced in 1930, the 85-5F was an 85 hp (63 kw) 5-cylinder, air-cooled, radial piston engine using aluminum cylinder heads and three bearings.

LeBlond 70-5E

Introduced in 1930, the 70-5E was a 70 hp (52 kw) 5-cylinder, air-cooled, radial piston engine. Production of the 5E continued in production under Ken-Royce as the Rearwin Ken-Royce 5E.

LeBlond 80-5F

Introduced in 1930, the 80-5F was an 80 hp (60 kw) 5-cylinder, air-cooled, radial piston engine with a displacement of 266 cubic inches (4.4 litres) Using three bearings as developed for the earlier 5DF series, the LeBlond 5F was introduced in 1930. When aircraft powered with the 5F were commandeered by the U.S. Army, the engine was re-designated the R-265. This engine was the last of the so-called 'greasers'. Production of the 5F continued under Ken-Royce as the Rearwin Ken-Royce 5G.

LeBlond 85-5DF

Introduced in 1930, the 85-5F was an 85 hp (63 kw) 5-cylinder, air-cooled, radial piston engine with a displacement of 266 cubic inches (4.4 litres)

LeBlond 90-5F

Introduced in 1930, the 90-5F was a 90 hp (68 kw) 5-cylinder, air-cooled, radial piston engine with a displacement of 266 cubic inches (4.4 litres)

LeBlond 90-5G

Introduced in 1930, the 90-5G was a 90 hp (68 kw) 5-cylinder, air-cooled, radial piston engine with a displacement of 266 cubic inches (4.4 litres) Production of the 5G continued under Ken-Royce as the Rearwin Ken-Royce 5G.

LeBlond 7 Variants

LeBlond 90-7D

Introduced in 1929, the 90-7D was a 90 hp (68 kw) 7-cylinder, air-cooled, radial piston engine using iron heads.

LeBlond 110-7DF

Introduced in 1930, the 110-7DF was a 110 hp (82 kw) 7-cylinder, air-cooled, radial piston engine using aluminum heads.

LeBlond 110-7F

A 110 hp (82 kw) 7-cylinder, air-cooled, radial piston engine using aluminum cylinder heads and three bearings. As with the 5F, the 7F continued in production under Ken-Royce as the Rearwin Ken-Royce 7G.

LeBlond 120-7

Introduced in 1929, the 120-7 was a 120 hp (89 kw) 7-cylinder, air-cooled, radial piston engine.

Parts interchangeable between the 5 and 7-cylinder models of the LeBlond and later Ken-Royce engines include the cylinder assemblies, gear case and oil pump. As the engine is modular in design, the gear case can be removed intact. The oil pump, being a single unit, can be removed from the bottom of the gear case for overhaul or replacement.

The Stromberg NAR-3 carburetor contains a built-in "primer" which acts like a choke by leaking gasoline into the intake stream when activated, in order to prime the engine.

The valve springs used on LeBlond's and Ken-Royce engines are of the volute spring type which is wound in a beehive shape out of strip steel. Unlike most engines, which have nested coil springs wound from round wire. This type of spring was inherited from the original Detroit Air-Cat as at the time of the Air-Cat design in the late twenties, round wire springs had resonance and fatigue problems. The volute design eliminated the resonance and lasted longer.