BMW IIIa was an inline six-cylinder SOHC valvetrain, water-cooled aircraft engine, the first-ever engine produced by Bayerische Flugzeugwerke AG, who, at the time, were exclusively an aircraft engine manufacturer. Its success laid the foundation for future BMW engine designs. It is best known as the powerplant of the Fokker D.VIIF, which outperformed any allied aircraft.
BMW IIIa
BMW IIIa at the Luftwaffenmuseum
An overhead camshaft (OHC) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion chamber in the engine block.
OHC cylinder head (for a 1987 Honda D15A3 engine)
SOHC design (for a 1973 Triumph Dolomite Sprint)
DOHC design (for a V12 engine)
Rubber timing belt during installation