Continuing to improve his early aircraft engines, Glenn Curtiss introduced his Model O in 1912 (per OX-5 Aviation Pioneers).
In 1913, an improved O called the OX was introduced. The OX powered the U.S. JN-4 Jenny and the British DH 6. The availability of the OX at surplus prices made it the engine of choice for many postwar aircraft.

Over 8,000 OX engines were produced.

models

• O: 75 hp (56 kW)
• OX: 90 hp (67 kW)

specifications

• Eight cylinders, water-cooled, vee
• 503 cubic inches (8.2 litres)

used by

• Curtiss Model D