Charles Keene of Los Angeles, California made a small aeronautical, three-cylinder radial engine running on Diesel.

“Charles Keene and his engine”

-It delivered 6 hp with an ingenious fuel injection system in the cylinder and a compression ratio of 16 to 1.

-Although it was designed for small planes, there were plans to build larger models on that base.

From Appendix 6: Some more information about the small Charles Keene aero engine in Los Angeles. Running on Diesel.

“Charles showing engine details”

-It has three radial cylinders and uses the two stroke cycle. The engine gave 6.3 hp at 2,000 rpm.