Rotax 912

Last updated

Rotax 912
3Xtrim3X55TrainerC-IFUF46Rotax912Sinstallation.jpg
Rotax 912ULS 100 hp (75 kW) installation in a 3Xtrim 3X55 Trener
Type Piston aircraft engine
National originAustria
Manufacturer Rotax Aircraft Engines
First run1984
Major applications Light sport aircraft
Ultralight aircraft
Produced1989–present
Variants Rotax 914
Rotax 915 iS
Rotax 912ULS 100 hp (75 kW) installation in a Blue Yonder Merlin EZ Rotax912SEngineInstallationMerlin.jpg
Rotax 912ULS 100 hp (75 kW) installation in a Blue Yonder Merlin EZ
Pusher engine installation of two Rotax 912ULSs in a Lockwood Aircam LezaLockwoodAirCamTwinRotax912SEngines.jpg
Pusher engine installation of two Rotax 912ULSs in a Lockwood Aircam
Rotax 912ULS with tuned exhaust in a Dyn'Aero MCR01 with 3-blade hydraulic CSU propeller Rotax912sDynAeroMcr01.jpg
Rotax 912ULS with tuned exhaust in a Dyn'Aéro MCR01 with 3-blade hydraulic CSU propeller

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. [1] Originally available only for light sport aircraft, ultralight aircraft, autogyros and drones, the 912-series engine was approved for certified aircraft in 1995. [2]

Contents

Design and development

The Rotax 912 was first sold in 1989 in non-certificated form for use in ultralights and motorgliders. [3] The original 80 hp (60 kW) 912 UL engine has a capacity of 1,211 cc (73.9 cu in) and a compression ratio of 9.1:1, and is designed to work with regular automotive gasoline, with up to 10% ethanol. The later certified 100 hp (75 kW) 912 ULS variant has a compression ratio of 11:1, and requires 91-octane ("premium") auto gas (100LL leaded avgas can be used, sparingly). [4]

The engine differs from previous generation aircraft engines (such as the Lycoming O-235) in that it has air-cooled cylinders with liquid-cooled heads [5] and uses a 2.43:1 PSRU reduction gearbox to reduce the engine's relatively high 5,800 rpm shaft speed to a more conventional 2,400 rpm for the propeller. The gearbox has proven to be generally trouble-free. [3] On the 912A, F and UL the standard reduction ratio is 2.27:1 with 2.43:1 optional. Lubrication is dry sump, and fuelling is via dual CV carburetors or fully redundant electronic fuel injection. The electronic fuel injected Rotax 912iS is a recent development. [5]

The 912's lubrication system differs from most dry-sump designs in that oil is forced into the storage tank by crankcase pressure rather than by a separate scavenge pump. This requires a novel preflight inspection procedure: before checking the oil level with the dipstick, 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. [3]

The 912 is more fuel efficient and lighter than comparable older engines, e.g., Continental O-200, but originally had a shorter time between overhaul (TBO). 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. The short TBO and lack of certification for use in factory-built type certificated aircraft initially restricted its worldwide market potential. However, the engine received US Federal Aviation Administration (FAA) certification in 1995, and by 1999, the TBO had increased to 1,200 hours; [3] on 14 December 2009, the TBO was raised from 1,200 hours to 1,500 hours, or 1,500 hours to 2,000 hours, depending on serial number. [6] In addition to the lower fuel consumption, the 912 is certified to run on automotive fuel (mogas), further reducing running costs, especially in areas where leaded avgas is not readily available. [5] The 912 may be operated using leaded fuel, but this is not recommended as lead sludge tends to accumulate in the oil tank and reduction gearbox. Also, avgas is incompatible with the recommended synthetic oil which cannot hold lead in suspension; consequently, the use of leaded fuel mandates additional maintenance. [3]

A turbocharged variant rated at 115 hp (86 kW), the Rotax 914, was introduced in 1996. In 1999, the 912S / ULS were introduced; [3] enlarged to 1,352 cubic centimetres (82.5 cu in) with a compression ratio of 10.8:1, yielding 100 hp (75 kW). The 912S is certified, as are the A and F, which are used in the Diamond DA20, which is quite popular in Europe. The 912's popularity was greatly enhanced by the introduction of the light-sport aircraft category in Europe and the United States, which resulted in the introduction of many factory-built aircraft designed to fully exploit the engine's small size and light weight. [3] The 100 hp (75 kW) versions are used in many light sport aircraft, such as the Zenith STOL CH 701 and the Tecnam P2002 Sierra. The 80 hp (60 kW) versions are sufficient to power the new generation of efficient motorgliders, such as the Pipistrel Sinus and the Urban Air Lambada. It is also fitted to some light twins, such as the Tecnam P2006T.

On 8 March 2012 the company displayed its 912 iS variant, a 100 hp (75 kW) version with fuel injection and an electronic engine management unit. [7] The version weighs 63 kg (139 lb), which is 6 kg (13 lb) more than the standard 912S. The non-certified 912 iS targets the light sport and homebuilt aircraft market and 912 iSc will be certified. Production started in March 2012 and the engine has a 2000-hour recommended time-between-overhaul to start. [8]

On 1 April 2014 the company announced its new 912 iS Sport upgrade with greater power and torque and reduced fuel consumption. [9] A further derivative, the 135 hp (101 kW) Rotax 915 iS, was announced in July 2015. [10]

Rotax's warnings to flyers

Unusually for a manufacturer of small aero-engines, Rotax publishes extensive warnings in the owner's manual about both the certified and non-certified versions of the engine design. Pilots are cautioned that the 912 engine is not suitable for:

The manual states that Rotax gives no assurances that the engine is suitable for use in any aircraft, and that the engine may seize or stall at any time, which could lead to a crash landing. The manual adds that non-compliance with such warnings could lead to serious injury or death. [11]

Variants

The engine is available in the following versions; coloured cylinder head caps are used to easily identify the different horsepower ranges:[ citation needed ]

912 A#
Certified to JAR 22, 80 hp (60 kW), with dual carburetors and electronic ignition. Black cylinder head caps
912 F#
Certified to FAR 33, 80 hp (60 kW), with dual carburetors and electronic ignition. Black cylinder head caps
912 iS
Uncertified, 100 hp (75 kW) with direct fuel injection and an electronic engine management unit. [8] Green cylinder head caps
912 iSc
Certified, 100 hp (75 kW) with direct fuel injection and an electronic engine management unit [8]
912 iS Sport
Uncertified, aluminum airbox, longer intake runners and eco-mode when operated below 97% power setting. [12] [13] Green cylinder head caps
912 iSC Sport

Green cylinder head caps

912 S#
Certified to FAR 33, 100 hp (75 kW) with larger bore than 912A/F/UL, with dual carburetors and electronic ignition. Green cylinder head caps
912 UL#
Uncertified, 80 hp (60 kW), similar to the 912A/F. Black cylinder head caps
912 ULS#
Uncertified, 100 hp (75 kW), similar to the 912S. Green cylinder head caps
912 ULSFR#
Uncertified French Authority specification. 100 hp (75 kW)

The # in the designation stands for:

  1. Shaft with flange for fixed pitch propeller, P.C.D. 100 mm
  2. Shaft with flange for fixed pitch propeller, P.C.D. 75 mm, P.C.D. 80 mm and P.C.D. 4 inches
  3. Shaft with flange for constant speed propeller P.C.D. 75 mm, P.C.D. 80 mm, P.C.D. 4 inches and drive for hydraulic governor for constant speed propeller
  4. Shaft with flange for fixed pitch propeller P.C.D. 75 mm, P.C.D. 80 mm, P.C.D. 4 inches also can be fitted with an adaptor, drive and governor for a constant speed propeller.

Applications

Specifications (Rotax 912 UL/A/F)

General characteristics

Components

Performance

Power density: 48.71 kW/L

Specific power: 0.98 kW/kg

See also

Comparable engines

Related lists

Related Research Articles

Rotax is the brand name for a range of internal combustion engines developed and manufactured by the Austrian company BRP-Rotax GmbH & Co KG, in turn owned by the Canadian Bombardier Recreational Products. Under the Rotax brand, the company is one of the world's largest producers of light piston engines.

<span class="mw-page-title-main">Continental O-200</span> Family of aircraft engines

The Continental C90 and O-200 are a family of air-cooled, horizontally opposed, four-cylinder, direct-drive aircraft engines of 201 in³ displacement, producing between 90 and 100 horsepower.

<span class="mw-page-title-main">Jabiru 2200</span> 1990s Australian piston aircraft engine

The Jabiru 2200 is a lightweight naturally aspirated, pushrod four-stroke, flat four, air-cooled aircraft engine produced by Jabiru Aircraft.

<span class="mw-page-title-main">Tecnam P92</span> Italian ultralight aircraft

The Tecnam P92 Echo and Tecnam P92 Eaglet are Italian high-winged, light aircraft, designed by Luigi Pascale and built by Tecnam of Naples.

<span class="mw-page-title-main">Rotax 914</span> Austrian turbocharged aircraft engine

The Rotax 914 is a turbo-charged, four-stroke, four-cylinder, horizontally opposed aircraft engine 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), as part of its Rotax brand.

<span class="mw-page-title-main">Ikarus C42</span> German ultralight aircraft

The Ikarus C42 is a two-seat, fixed tricycle gear, general aviation microlight aircraft, manufactured in Germany by Comco Ikarus. It is used primarily for flight training, touring and personal flying.

<span class="mw-page-title-main">Rotax 582</span> Austrian two-stroke aircraft engine

The Rotax 582 is a 48 kW (64 hp) two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating in day visual flight rules.

<span class="mw-page-title-main">ULPower UL260i</span>

The ULPower UL260i is a family of aircraft engines, produced by ULPower in Belgium.

The Rotax 447 is a 41.6 hp (31 kW), inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.

The Hirth 2704 and 2706 are a family of in-line twin cylinder, two stroke, carburetted aircraft engines, with optional fuel injection, designed for use on ultralight aircraft and especially two seat ultralight trainers, single seat gyrocopters and small homebuilts. It was manufactured by Hirth of Germany.

The Hirth F-30 is a horizontally opposed four-cylinder, two-stroke, carburetted aircraft engine, with optional fuel injection, designed for use on ultralight aircraft and homebuilts. It is manufactured by Hirth of Germany.

<span class="mw-page-title-main">HKS 700E</span>

The HKS 700E is a twin-cylinder, horizontally opposed, four stroke, carburetted aircraft engine, designed for use on ultralight aircraft, powered parachutes and ultralight trikes. The engine is manufactured by HKS, a Japanese company noted for its automotive racing engines.

<span class="mw-page-title-main">Tecnam P2006T</span> Twin-engine general aviation aircraft

The Tecnam P2006T is an Italian high-winged twin-engined all-metal light aircraft, built by Costruzioni Aeronautiche Tecnam based in Capua, Italy, near Naples. The P2006T received airworthiness certification in the European Union by EASA under CS23 in 2003, type certification in 2009, and Federal Aviation Administration FAR Part 23 certification in 2010.

<span class="mw-page-title-main">Tecnam P2002 Sierra</span> Italian light aircraft

The Tecnam P2002 Sierra is a two-seat, low-wing, light aircraft designed and constructed by the Italian aircraft manufacturer Tecnam. Introduced during the early 2000s, the aircraft quickly became a staple of the company's product lineup, comprising 70 per cent of its available production capacity during some years.

<span class="mw-page-title-main">TL Ultralight TL-96 Star</span> Czech ultralight aircraft

The TL Ultralight TL-96 Star is a single-engine, side-by-side configuration two seat ultralight, designed in the Czech Republic in the 1990s. More than 150 have been registered.

The Hewland AE75 is a lightweight aircraft engine that was manufactured in the mid-1980s by Hewland in Maidenhead, United Kingdom. The engine, a two-stroke inverted inline triple of 750 cc (46 cu in) displacement, is liquid-cooled and yields 75 hp (56 kW)

<span class="mw-page-title-main">Alpi Pioneer 200</span> Italian ultralight aircraft

The Alpi Pioneer 200 is an Italian ultralight and light-sport aircraft, designed and produced by Alpi Aviation, of Pordenone. The aircraft is supplied as a kit for amateur construction or as a complete ready-to-fly-aircraft.

<span class="mw-page-title-main">Tecnam Astore</span> Italian sport aircraft

The Tecnam Astore is an Italian, low wing, two-seater, light-sport aircraft, under development by Tecnam of Naples. It was first flown in early June, 2013, and introduced at the AERO Friedrichshafen show in 2013. It is supplied complete and ready-to-fly.

The Tecnam Snap is an Italian aerobatic ultralight aircraft, designed by Fabio Russo and produced by Tecnam of Casoria, Metropolitan City of Naples, introduced at the AERO Friedrichshafen show in 2013. The aircraft was intended to be supplied complete and ready-to-fly.

<span class="mw-page-title-main">Tecnam P96 Golf</span> Type of aircraft

The Tecnam P96 Golf is an Italian all-metal side-by-side two-seat single-engine, low wing light aircraft that was designed by Luigi Pascale and built by Tecnam in Naples from 1997 to 2006.

References

  1. "Rotax Rolls Out 50,000 912-Series Engine". 6 June 2014. Retrieved 7 June 2014.
  2. Federal Aviation Administration (11 October 2016). "Type Certificate Data Sheet No. E00051EN" (PDF). Archived (PDF) from the original on 13 November 2016. Retrieved 16 August 2020.
  3. 1 2 3 4 5 6 7 Busch, Mike (1 June 2017). "Opinion: Savvy Maintenance - Outside the Box: The Rotax 912 is Delightfully Different". AOPA Pilot. Aircraft Owners and Pilots Association . Retrieved 10 April 2020.
  4. Prizio, Dave: "Firewall Forward: Rotax service Training," July 19, 2013, Kitplanes, retrieved July 5, 2023
  5. 1 2 3 Rotax (September 2012). "Operators Manual for Rotax engine type 912 series" (PDF). Retrieved 21 June 2015.
  6. Rotax (December 2009). "Extension of Time Between Overhauls (TBO) for Rotax Engine Type 912 and 914 (Series)" (PDF). Retrieved 11 February 2010.
  7. "Rotax Introduces 921iS". Sport Aviation: 14. May 2012.
  8. 1 2 3 Bertorelli, Paul (8 March 2012). "BRP/Rotax Rolls Out New Engine". AVweb. Retrieved 14 March 2012.
  9. "Rotax lowers fuel burn, boosts performance with 912 iS Sport". aopa.org. April 2014. Retrieved 22 July 2015.
  10. "Rotax-Owner.com - ROTAX 915 IS: BRP UNVEILS A NEW TURBOCHARGED ROTAX AIRCRAFT ENGINE". rotax-owner.com. Retrieved 22 July 2015.
  11. BRP-Rotax (1 September 2012). "Operators Manual Rotax Type 912 Series" (PDF). Archived from the original (PDF) on 30 June 2014. Retrieved 5 August 2014.
  12. Sport Aviation: 14. May 2014.{{cite journal}}: Missing or empty |title= (help)
  13. "Rotax 912 iS: Better than predicted". generalaviationnews.com. 27 June 2013. Retrieved 10 August 2016.