View source for Rotax 914

{{Short description|Austrian turbocharged aircraft engine}}
{{Use dmy dates|date=October 2023}}
{{Use American English|date=March 2023}}
<!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. -->
{|{{Infobox aircraft begin
 | name=914
 | image=Rotax 914.jpg
 | caption=
}}{{Infobox aircraft engine
 |type=[[Piston]] [[aircraft engine]]
 |manufacturer=[[Rotax]]
 |national origin=Austria
 |first run=
 |major applications=[[Light aircraft]], [[unmanned aerial vehicle]]s
 |produced= 1996–present<ref>{{cite news |url= https://www.rotax.com/de/news/aktuelles/details/id-40-years-of-rotax-aircraft-engines-152.html |title= 40 years of rotax aircraft engines |date= 30 June 2015 |publisher= Rotax}}</ref><ref name=AOPA_2017>{{cite news |last=Busch |first=Mike  |date=1 June 2017 |title=Opinion: Savvy Maintenance – Outside the Box: The Rotax 912 is Delightfully Different |url=https://www.aopa.org/news-and-media/all-news/2017/june/pilot/savvy-maintenance-rotax-912 |work=AOPA Pilot |publisher=[[Aircraft Owners and Pilots Association]] |access-date=10 April 2020 }}</ref>
|number built=
 |developed from=[[Rotax 912]]
 |variants with their own articles=
}}
|}

The '''Rotax 914''' is a [[turbo-charged]], [[four-stroke]], [[four-cylinder]], [[horizontally opposed]] [[aircraft engine]] with [[air-cooled]] cylinders and [[water-cooled]] [[cylinder head]]s. It is designed and built by the Austrian company BRP-Powertrain, owned by [[Bombardier Recreational Products]]  (BRP), as part of its [[Rotax]] brand.<ref name="WDLA11">Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisure Aviation 2011-12'', pages 242-243. WDLA UK, Lancaster UK, 2011. {{ISSN|1368-485X}}</ref><ref name="WDLA15">Tacke, Willi; Marino Boric; et al: ''World Directory of Light Aviation 2015-16'', pages 260-261. Flying Pages Europe SARL, 2015. {{ISSN|1368-485X}}</ref><ref>{{cite web|url = http://www.rotax.com/en/Engine/2004/Aircraft/Engine.Models.htm|title = Engine Models|access-date = 13 March 2020|author=Rotax|author-link=Rotax|work = rotax.com|year=2005|archive-url = https://web.archive.org/web/20070318041653/http://www.rotax.com/en/Engine/2004/Aircraft/Engine.Models.htm|archive-date =18 March 2007 }}</ref>

The engine commonly powers [[type certificate|certified]] light aircraft, [[homebuilt aircraft]], [[autogyro]]s and military [[Unmanned aerial vehicle|UAVs]] such as the [[MQ-1 Predator]].

==Design and development==
Introduced in 1996, the Rotax 914 is a turbocharged development of the [[Rotax 912]].<ref name=AOPA_2017/>

The Rotax 914 has a [[turbocharger]] with an automatic [[wastegate]] controller and dual [[carburetor]]s. It features [[dual ignition|dual]] [[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.<ref name="WDLA11"/><ref name="WDLA15"/><ref name="Official">{{cite web|url = https://www.flyrotax.com/produkte/detail/rotax-914-ul-f.html|title = Rotax 914 UL/F|access-date = 13 March 2020|author=Rotax|author-link=Rotax|work = flyrotax.com|archive-url = https://web.archive.org/web/20180915192315/https://www.flyrotax.com/produkte/detail/rotax-914-ul-f.html|archive-date = 15 September 2018}}</ref>

The 914 oil system differs from most dry-sump designs in that lubricating 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.<ref name=AOPA_2017/>

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.<ref name=AOPA_2017/>

The engine can be operated on 100LL [[Tetraethyllead|leaded]] [[avgas]] or on unleaded regular automotive [[gasoline]], with a minimum [[Octane rating#RON|RON]] of 95.<ref name="WDLA15"/><ref name="E00058NE">{{cite web|url = https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/6ece3d1578b2dbde86258050006c1ff7/$FILE/E00058NE_Rev4.pdf|title = Type Certificate Data Sheet No. E00058NE Revision 4|access-date = 13 March 2020|author = Federal Aviation Administration|author-link = Federal Aviation Administration|date = 11 October 2016|archive-url =https://web.archive.org/web/20161113024244/https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/6ece3d1578b2dbde86258050006c1ff7/$FILE/E00058NE_Rev4.pdf |archive-date =13 November 2016}}</ref> 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]] because it cannot hold lead in suspension; consequently, using leaded fuel mandates additional maintenance, and unleaded fuel is recommended.<ref name=AOPA_2017/>

==Variants==
;914 F
:Family of engine versions certified to US [[Federal Aviation Administration]] [[Federal Aviation Regulations|FAR 33]] and [[EASA]] JAR-E. These include:<ref name="WDLA15"/><ref name="Official"/><ref name="E00058NE"/><ref name="EASA">{{cite web|url = https://www.easa.europa.eu/sites/default/files/dfu/TCDS_E%20122_Issue06_20160509_1.0.pdf|title = EASA Aircraft Type Certificates – E.122 |access-date = 14 March 2020|author = European Aviation Safety Agency|author-link = European Aviation Safety Agency|date = 5 September 2016|archive-url = https://web.archive.org/web/20200314155307/https://www.easa.europa.eu/sites/default/files/dfu/TCDS_E%20122_Issue06_20160509_1.0.pdf|archive-date =14 March 2020}}</ref> 
:*'''914 F2''': Version equipped to accept a fixed pitch [[Propeller (aeronautics)|propeller]].<ref name="E00058NE"/><ref name="EASA"/>
:*'''914 F3''': Version equipped with a hydraulic governor for a [[constant speed propeller]].<ref name="E00058NE"/><ref name="EASA"/>
:*'''914 F4''': Version equipped to accept a hydraulic governor for a constant speed propeller.<ref name="E00058NE"/><ref name="EASA"/>
;914 UL
:Non-certified engine version for [[homebuilt aircraft|homebuilt]] and [[ultralight aircraft]].<ref name="WDLA15"/><ref name="Official"/>

==Applications==
{{columns-list|colwidth=22em|
*[[Aero Adventure Pegasus]]
*[[Aerospool WT9 Dynamic]]
*[[Aerospool WT10 Advantic]]
*[[Air Copter A3C]]
*[[Alisport Yuma]]
*[[Alpi Pioneer 300]]
*[[Alpi Pioneer 400T]]
*[[Australian Aircraft Kits Hornet STOL]]
*[[AutoGyro MT-03]]
*[[AutoGyro Calidus]]
*[[AutoGyro Cavalon]]
*[[Aviomania Genesis Duo G2SA]]
*[[B&F Fk14 Polaris]]
*[[Bauer BAD-12 Gyrotrainer]]
*[[Blackshape Prime]]
*[[Bushcaddy R-80]]
*[[Bushcaddy R-120]]
*[[The Butterfly Super Sky Cycle]]
*[[Celier Kiss]]
*[[Celier Xenon 2]]
*[[Chayair Sycamore]]
*[[Criquet Storch]]
*[[Denel Dynamics Bateleur]]
*[[Diamond HK36 Super Dimona]]
*[[Dorna Parandeh Abi]]
*[[Dova DV-1 Skylark]]
*[[DTA J-RO]]
*[[Dyn'Aéro MCR4S]]
*[[Dynali H2S]]
*[[Dynali H3 EasyFlyer]]
*[[ELA 07]]
*[[ELA 10 Eclipse]]
*[[Elbit Hermes 900]]
*[[Eurodisplay SR-01 Magic]]
*[[Europa XS]]
*[[FD-Composites ArrowCopter]]
*[[Flying Legend Hawker Hurricane Replica]]
*[[General Aviation Design Bureau T-32 Maverick]]
*[[HB Flugtechnik HB-207 Alfa]]
*[[Heli-Sport CH-7|Heli-Sport CH-7 Kompress]] helicopter
*[[Heli-Sport CH77 Ranabot]] helicopter
*[[Ibis GS-501 Urraco]]
*[[IAI Heron]]
*[[Idea Hydropteron]]
*[[Just Superstol]]
*[[Magni M-14 Scout]]
*[[Magni M-24 Orion]]
*[[Qods Mohajer-6]] 
*[[M&D Flugzeugbau Samburo]] 
*[[MQ-1 Predator]]
*[[NAL Hansa]]
*[[Norman Aviation Nordic VI]]
*[[Norman Aviation Nordic 8 Mini Explorer]]
*[[Pagotto Brakogyro]]
*[[Pelegrin Tarragon]]
*[[Phenix Aviation Phenix]]
*[[Progressive Aerodyne SeaRey]]
*[[RMT Bateleur]]
*[[Roko Aero NG4]]
*[[Rokospol Via]]
*[[Rotor Flight Dynamics Dominator]]
*[[RotorSport UK Calidus]]
*[[RotorSport UK MT-03]]
*[[Rotorvox C2A]]
*[[Scheibe Falke]]
*[[Shaanxi Baojii Special Vehicles Lie Ying Falcon]]
*[[Shahed 129]]
*[[SkyCruiser Autogyro SkyCruiser]]
*[[SkyStar Pulsar]]
*[[Softeks V-24 Lastochka]]
*[[Sonaca 200]]
*[[SlipStream Genesis]]
*[[Stemme S10]] motor glider
*[[Storm 300]]
*[[Storm RG Fury]]
*[[Titan T-51 Mustang]]
*[[Titanium Explorer]]
*[[TL-Ultralight Stream]]
*[[Trixy Liberty]]
*[[Ultravia Pelican]]
*[[Wild DoubleEnder]]
*[[Wüst Seahawk]]
}}

==Specifications (914)==
{{pistonspecs|
<!-- If you do not understand how to use this template, please ask at [[Wikipedia talk:WikiProject Aircraft]] -->
<!-- Please include units where appropriate (main comes first, alt in parentheses). If data are missing, leave the parameter blank (do not delete it). For additional lines, end your alt units with )</li> and start a new, fully formatted line with <li> -->
|type=four-cylinder, four-stroke liquid- / air-cooled engine with opposed cylinders
|bore={{convert|79.5|mm|in|abbr=on}}
|stroke={{convert|61|mm|in|abbr=on}}
|displacement={{convert|1211.2|cc|cuin|abbr=on}}
|length={{convert|561|mm|in|abbr=on}}
|diameter= 
|width={{convert|576|mm|in|abbr=on}}
|height= 
|weight={{convert|78|kg|lbs|abbr=on}} with electric starter, carburetors, fuel pump, air filters and oil system
|valvetrain=OHV, hydraulic lifters, pushrods, rocker arms 
|supercharger=
|turbocharger=
|fuelsystem=Dual CD carburetors, dual electric pumps
|fueltype=Unleaded: 91 octane AKI (Canada/USA) / 95 octane RON (European) or higher<ref>OM-914 Operator's Manual 914 Series</ref>
|oilsystem=Dry sump with [[trochoid pump]], camshaft driven 
|coolingsystem=Liquid-cooled cylinder heads, air-cooled cylinders 
|power = Maximum 84&nbsp;kW (115&nbsp;hp) at 5,800 rpm, with 5 minute time limit; 73&nbsp;kW (100&nbsp;hp) continuous
|specpower=
|compression=
|fuelcon=
|specfuelcon=
|oilcon=
|power/weight=

|designer=
|reduction_gear = Integrated reduction gear 1:2.273; 1:2.43 optional

|general_other=
|components_other=Electronic dual ignition
|performance_other=
}}

==See also==
{{aircontent
<!-- include as many lines are appropriate. additional lines/entries with carriage return. -->
|see also=
*[[Rotax#Aircraft engines|Rotax aircraft engines]]
|related=<!-- related developments -->
|similar engines=
|lists= 
*[[List of aircraft engines]]
}}

==References==
{{Reflist}}

==External links==
{{Commons category}}
*{{Official website|https://www.flyrotax.com/produkte/detail/rotax-914-ul-f.html}}

{{Rotax aeroengines}}

[[Category:Boxer engines]]
[[Category:Rotax engines]]
[[Category:1990s aircraft piston engines]]