Lycoming O-290

O-290
TypePiston aircraft engine
National originUnited States
ManufacturerLycoming Engines
First run1939
Major applications
Manufactured1942–1975 out of production
Developed intoLycoming O-435

The Lycoming O-290 is a dual-ignition, four-cylinder, air-cooled, horizontally opposed aircraft engine. It was first run in 1939, and entered production three years later.

A common variant of the type is the O-290-G, a single-ignition model which was designed to drive a generator as part of a ground power unit.