The Rotax 914 is a turbo-charged,

four-stroke A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either directio ...

four-cylinder The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized. Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categorize ...

horizontally opposed A flat engine is a piston engine where the cylinders are located on either side of a central crankshaft. Flat engines are also known as horizontally opposed engines, however this is distinct from the less common opposed-piston engine design, wh ...

aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...

with air-cooled cylinders and water-cooled cylinder heads. It is designed and built by the Austrian company BRP-Powertrain, owned by

Bombardier Recreational Products BRP Inc. is the holding company for Bombardier Recreational Products Inc., operating as BRP, a Canadian manufacturer of snowmobiles, all-terrain vehicles, side by sides, motorcycles, and personal watercraft. It was founded in 2003, when the Recr ...

(BRP), as part of its Rotax brand.Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisure Aviation 2011-12'', pages 242-243. WDLA UK, Lancaster UK, 2011. Tacke, Willi; Marino Boric; et al: ''World Directory of Light Aviation 2015-16'', pages 260-261. Flying Pages Europe SARL, 2015. The engine commonly powers

certified Certification is the provision by an independent body of written assurance (a certificate) that the product, service or system in question meets specific requirements. It is the formal attestation or confirmation of certain characteristics of a ...

light aircraft, homebuilt aircraft, autogyros and military UAVs such as the MQ-1 Predator.

Design and development

Introduced in 1996, the Rotax 914 is a turbocharged development of the

Rotax 912 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, late ...

. The Rotax 914 has a turbocharger with an automatic wastegate controller and dual

carburettor A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meterin ...

s. It features

dual Dual or Duals may refer to: Paired/two things * Dual (mathematics), a notion of paired concepts that mirror one another ** Dual (category theory), a formalization of mathematical duality *** see more cases in :Duality theories * Dual (grammatical ...

capacitor discharge ignition, liquid-cooled cylinder heads and air-cooled cylinder barrels, an electric starter, a built in propeller reduction gearbox, dry sump forced oil lubrication and has a separate oil tank. It has hydraulic valves that include automatic adjustment. Rotax can provide a purpose-designed air intake, exhaust system and engine mount. The 914 oil system differs from most dry-sump designs in that lubricating oil is forced into the storage tank by

crankcase In a piston engine, the crankcase is the housing that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel/a ...

pressure rather than by a separate scavenge pump. This requires a novel

preflight inspection In aviation, an outside check or walk around is the air crew inspecting certain elements of an aircraft prior to boarding for security, safety, and operational reasons. The pilot primarily inspects outside parts of the aircraft they will ste ...

procedure: before checking the oil level with the

dipstick A dipstick is one of several measurement devices. Some dipsticks are dipped into a liquid to perform a chemical test or to provide a measure of quantity of the liquid. Since the late 20th century, a flatness/levelness measuring device trademarke ...

, the engine is "burped" by removing the oil filler cap and turning the propeller until a gurgling sound is heard, which indicates that all oil has been forced into the tank and the oil level can now be checked accurately. The 914 is more fuel efficient and lighter than similarly sized traditional engines, but originally had a shorter time between overhaul (TBO), restricting its market potential. On introduction, the TBO was only 600 hours, which was double that of previous Rotax engines but far short of existing engines of comparable size and power. However, by 1999 the TBO had been increased to 1,000 hours, and it was increased again to 2,000 hours in 2010. The engine can be operated on 100LL leaded

avgas Avgas (aviation gasoline, also known as aviation spirit in the UK) is an aviation fuel used in aircraft with spark-ignited internal combustion engines. ''Avgas'' is distinguished from conventional gasoline (petrol) used in motor vehicles, w ...

or on unleaded regular automotive gasoline, with a minimum RON of 95. If the 914 is operated using leaded fuel, lead sludge will accumulate in the oil tank and reduction gearbox, and the fuel is incompatible with the recommended

synthetic oil Synthetic oil is a lubricant consisting of chemical compounds that are artificially modified or synthesised. Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be syn ...

because it cannot hold lead in suspension; consequently, using leaded fuel mandates additional maintenance, and unleaded fuel is recommended.

Variants

;914 F :Family of engine versions certified to US Federal Aviation Administration FAR 33 and EASA JAR-E. These include: :*914 F2: Version equipped to accept a fixed pitch

propeller A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

. :*914 F3: Version equipped with a hydraulic governor for a constant speed propeller. :*914 F4: Version equipped to accept a hydraulic governor for a constant speed propeller. ;914 UL :Non-certified engine version for

homebuilt Homebuilt machines are machines built outside of specialised workshops or factories. This can include different things such as kit cars or homebuilt computers, but normally it pertains to homebuilt aircraft, also known as amateur-built aircraft ...

and

ultralight aircraft Ultralight aviation (called microlight aviation in some countries) is the flying of lightweight, 1- or 2-seat fixed-wing aircraft. Some countries differentiate between weight-shift control and conventional three-axis control aircraft with ailer ...

Design and development

Variants

Applications

Specifications (914)

See also

References

External links