The Rotax 914 is a

turbo-charged In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into the ...

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 categoriz ...

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, ...

aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbin ...

with

air-cooled Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. Air-cooled designs are far simpler than their liquid-cooled ...

cylinders and

water-cooled Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and no ...

cylinder head In a piston engine, the cylinder head sits above the cylinders, forming the roof of the combustion chamber. In sidevalve engines the head is a simple plate of metal containing the spark plugs and possibly heat dissipation fins. In more modern ...

s. It is designed and built by the Austrian company BRP-Powertrain, owned by

Bombardier Recreational Products BRP Inc. (an abbreviation of Bombardier Recreational Products) is a Canadian manufacturer of snowmobiles, all-terrain vehicles, Side-by-side (vehicle), side by sides, motorcycles, and personal watercraft. It was founded in 2003, when the Recreati ...

(BRP), as part of its

Rotax Rotax is the brand name for a range of internal combustion engines developed and manufactured by the Austrian company BRP-Rotax GmbH & Co KG (until 2016 BRP-Powertrain GmbH & Co. KG), in turn owned by the Canadian Bombardier Recreational Prod ...

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 part of testing, inspection and certification and 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 attestatio ...

light aircraft,

homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

autogyro An autogyro (from Greek and , "self-turning"), gyroscope, gyrocopter or gyroplane, is a class of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. A gyroplane "means a rotorcraft whose rotors are not engine-d ...

s and military

UAVs An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Drone ...

such as the

MQ-1 Predator The General Atomics MQ-1 Predator (often referred to as the Predator drone) is an American remotely piloted aircraft (RPA) built by General Atomics that was used primarily by the United States Air Force (USAF) and Central Intelligence Agency ...

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, la ...

. The Rotax 914 has a

turbocharger In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into th ...

with an automatic

wastegate A wastegate is a valve that controls the flow of exhaust gases to the turbine wheel in a turbocharged engine system.Robson, D. (2018). Aircraft General Knowledge. Aviation Theory Centre Pty Ltd. . Diversion of exhaust gases regulates the turbine ...

controller and dual

carburetor A carburetor (also spelled carburettor or carburetter) is a device used by a gasoline 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 Ventu ...

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 number, a nu ...

capacitor discharge ignition Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, gas turbine-powered aircraft, and some cars ...

, liquid-cooled cylinder heads and air-cooled cylinder barrels, an electric starter, a built in propeller

reduction gearbox An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the ...

dry sump A dry sump system is a method to manage the lubricating motor oil in Four-stroke engine, four-stroke and large Two-stroke engine, two-stroke Reciprocating engine, reciprocating internal combustion engines. The dry sump system uses two or more o ...

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 A crankcase is the housing in a reciprocating engine, piston engine 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, res ...

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

, 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 Time between overhauls (abbreviated as TBO or TBOH) is the manufacturer's recommended number of running hours or calendar time before an aircraft engine or other component requires overhaul. On rotorcraft, many components have recommended or ma ...

(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 United Kingdom, UK) is an aviation fuel used in aircraft with spark-ignited internal combustion engines. ''Avgas'' is distinguished from conventional gasoline (petrol) used in moto ...

or on unleaded regular automotive

gasoline Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When for ...

, with a minimum

RON Ron is a shortening of the name Ronald. Ron or RON may also refer to: Arts and media * Big Ron (''EastEnders''), a TV character * Ron (''King of Fighters''), a video game character *Ron Douglas, the protagonist in '' Lucky Stiff'' played by Joe ...

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 oil is used as a substitute for petroleum-refined oils when operating in extreme temperature, in metal stamping to provide en ...

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 The Federal Aviation Administration (FAA) is a Federal government of the United States, U.S. federal government agency within the United States Department of Transportation, U.S. Department of Transportation that regulates civil aviation in t ...

FAR 33 and

EASA The European Union Aviation Safety Agency (EASA) is an agency of the European Commission with responsibility for civil aviation safety in the European Union. It carries out certification, regulation and standardisation and also performs inve ...

JAR-E. These include: :*914 F2: Version equipped to accept a fixed pitch

propeller A propeller (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 a working flu ...

. :*914 F3: Version equipped with a hydraulic governor for a

constant speed propeller Constant or The Constant may refer to: Mathematics * Constant (mathematics), a non-varying value * Mathematical constant, a special number that arises naturally in mathematics, such as or Other concepts * Control variable or scientific con ...

. :*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 or ...

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 Aircraft flight control system, conventional three-a ...

Design and development

Variants

Applications

Specifications (914)

See also

References

External links