The Rotax 912 is a horizontally-opposed four-cylinder, naturally-aspirated, four-stroke aircraft engine with a reduction gearbox. It features liquid-cooled cylinder heads and air-cooled cylinders. Originally equipped with carburetors, later versions are fuel injected. Dominating the market for small aircraft and kitplanes, Rotax produced its 50,000th 912-series engine in 2014. Originally available only for light sport aircraft, ultralight aircraft, autogyros and drones, the 912-series engine was approved for certified aircraft in 1995.
Rotax 912
Rotax 912ULS 100 hp (75 kW) installation in a Blue Yonder Merlin EZ
Pusher engine installation of two Rotax 912ULSs in a Lockwood Aircam
Rotax 912ULS with tuned exhaust in a Dyn'Aéro MCR01 with 3-blade hydraulic CSU propeller
A flat-four engine, also known as a horizontally opposed-four engine or boxer engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, each pair of opposed pistons moves inwards and outwards at the same time.
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