The Rotax 912 ULS is a 4-cylinder, 4-stroke, horizontally opposed aircraft piston engine widely used in light sport aircraft, ultralights, and experimental aircraft. It combines liquid-cooled cylinder heads and air-cooled cylinders, with a dry-sump lubrication system and separate oil tank.

It is equipped with a propeller reduction gearbox (Type 2 configuration, i = 2.43) and an integrated overload clutch, which protects the crankshaft and gearbox from sudden propeller shock loads.

Key features:

100 HP (73.5 kW) output at 5800 RPM
Gearbox reduction ratio i = 2.43 : 1
Integrated torsional overload clutch (Type 2 gearbox system)
Dual carburetors
Dual independent electronic ignition systems
Dry-sump lubrication with external oil tank
Electric starter
Mechanical fuel pump
Horizontally opposed 4-cylinder layout
FAA/EASA certified variants available (912 S / ULS depending configuration)