Wikipedia:WikiProject Aircraft/Engines/page content

Naming
Every article in Wikipedia has a name, aero engine articles are named by their manufacturer, then by name and/or designation number, for example Rolls-Royce Nene, Pratt & Whitney R-1340.

Aircraft engine articles should always be named as generally as possible using the common name except for engines with United States military designations.
 * US military designated engines should use the designator and not the name.
 * If more than one engine type has the same name then a suffix should be used for the least common engine, for example Rolls-Royce Eagle (1944).

Article structure
It is desirable that aircraft engine articles follow the main WP:AIR/PC page content guidelines with some minor differences in the upper sections. A suggested article structure is given below:


 * Lead
 * Table of Contents
 * Design and development
 * Variants
 * Applications
 * Survivors
 * Engines on display
 * Specifications
 * See also
 * References
 * Further reading
 * External links

Lead
For general advice on lead section contents see Lead section. The lead of an aero engine article should contain the following basic information when known:


 * Name/designation.
 * Manufacturer.
 * Nationality.
 * Type (e.g. turboprop, radial engine).
 * Timeframe (e.g. World War II or 'produced between 19XX and 19XX'.
 * Number built.
 * Major aircraft type applications.

Citations are not required in the lead section if the facts are cited elsewhere in the article text and are unlikely to be challenged (see WP:LEADCITE).

Applications
It is usual to list all known aircraft type applications from reliable sources (including testbeds) for aero engines. For ship or land vehicle applications a sub-header is often used for clarity, i.e. Other applications or Alternative uses. Larger lists can be formatted into columns using Template:Columns-list to save page length and white space. It is advisable to add a note or cite any unusual or contentious applications that may be questioned by other editors.

Survivors/Engines on display sections

 * The survivors section relates to airworthy, older, out of production engines, that are currently powering vintage aircraft types.
 * Engines on display should include museum exhibits that are accessible to the public.

See also section
See also sections are completed using the Aircontent template. Please include the list of aircraft engines for every type. For 'comparable' engines it is desirable to limit the number of entries by selecting the closest similar types. Some useful parameters are era, layout, number of cylinders, engine displacement and power/thrust rating.

Images

 * It is highly desirable that the infobox image shows a complete and uncowled engine where available.
 * Images of rarer aircraft types using the engine may be used in the 'applications' section of longer articles.
 * Images of component parts or drawings/diagrams are encouraged in the relevant sections

Grammatical tense
Confusion can arise as to which tense to use in an engine article, the following guidelines may help:
 * If the article has a 'survivors' section (flying engines) then the first lead sentence should be present tense.
 * If the engine is extinct or only found in museums then use past tense throughout.

Units
Units in specification tables and main article text should follow those used by the original manufacturer, e.g., the Rolls-Royce Merlin being a British engine uses Imperial units primarily where the Daimler-Benz DB 605 uses the Metric system. Conversions should be provided where possible using the guidelines at Manual of Style/Dates and numbers.

Engine specifications
Engine specifications are generated using one of two templates, either Pistonspecs for reciprocating engines (including Wankel type rotaries) or Jetspecs for all gas turbines. Each article should only contain one set of specifications and any model differences should be described in the variants or development sections. Multiple sets of specifications are to be avoided.


 * Tips and tricks
 * In the section header specify the variant described when known, omitting the manufacturer unless it is a licensed built variant e.g. "Specifications (Merlin 66)" or "Specifications (J79-15)".
 * Non-breaking spaces are not required in specification templates.
 * Avoid false precision. Where the specifications are cited by a reliable source the figures and conversions may differ from that obtained with a calculator or conversion programme, per Verifiability they should be left uncorrected.
 * Often it is easier to copy the specifications from an existing similar article but be sure to change the figures to those given in your cited reference.
 * An image of the engine (or a technical drawing) can be used to effectively fill the white space that occurs on the right side of the table.
 * In the examples given below simply reverse the units for engines with metric dimensions.

Explanation of pistonspecs template parameters

 * type= Engine in a nutshell, #-cylinder turbo/supercharged air/liquid-cooled inline/rotary/V-# piston aircraft engine
 * designer= Who
 * bore= Diameter of each cylinder, in (mm)
 * stroke= Distance the piston travels inside the cylinder, in (mm)
 * displacement= Total volume of the engine, in³ (L)
 * length= Length of the engine, in (mm)
 * diameter= Diameter or width of the engine, in (mm)
 * width= Width of the engine, in (mm)
 * height= Height of the engine, in (mm)
 * weight= Dry weight of the engine (without oil, coolant, etc.), lb (kg)
 * valvetrain= Description of valves, including number of intake/exhaust valves per cylinder and valve operation (camshaft/pushrod, OHV/OHC), for example two pushrod-actuated valves per cylinder with sodium-cooled exhaust valve or overhead camshaft-actuated, two intake and two exhaust valves per cylinder, sodium-cooled exhaust valve stems
 * supercharger= Description of the supercharger, leave blank if not installed, for example two-speed two-stage, boost pressure automatically linked to the throttle, water-air aftercooler installed between the second stage and the engine
 * turbocharger= Description of the turbocharger, leave blank if not installed.
 * fuelsystem= Description of the fuel system (carbutered/fuel injected, etc.), for example twin-choke updraft carburetor with automatic mixture control
 * fueltype= Fuel type, octane rating
 * oilsystem= Description of the oil system, for example dry sump with one pressure pump and two scavenge pumps
 * coolingsystem= Description of the cooling system, for example 70% water and 30% ethylene glycol coolant mixture, pressurized. At the very least say if the engine was air- or liquid-cooled.
 * reduction_gear If there's one, give the ratio or otherwise describe it
 * power= Power output, hp (kW) at # rpm
 * specpower= Specific power, power output divided by engine displacement; hp/in³ or kW/l
 * compression= Compression ratio, #:1
 * fuelcon= Fuel consumption, US gal/h (L/h) or lb/h (kg/h)
 * specfuelcon= Specific fuel consumption lb/(hp·h) (kg/(kW·h))
 * oilcon= Oil consumption US gal/h (L/h) or lb/h (kg/h)
 * power/weight= Power-to-weight ratio, calculated by dividing engine power by engine weight, hp/lb (kW/kg)

Explanation of jetspecs template parameters

 * type= Engine in a nutshell, afterburning turbofan/turbojet/turboshaft/turboprop engine
 * length= Length of the engine, in (mm)
 * diameter= Diameter or width of the engine, in (mm)
 * weight= Dry weight of the engine (without oil, coolant, etc.), lb (kg)
 * compressor= Description of the compressor (number of stages, high/low pressure stages, number of blades, etc.), for example single-stage dual-entry centrifugal compressor with two-sided impeller (axial compressor should also be wiki-linked). At the very least specify if it is an axial or a centrifugal compressor.
 * combustion= Description of the combustion chambers, for example 10 flow combustion chambers with igniter plugs in chambers 3 and 10
 * turbine= Description of the turbine, for example single-stage axial flow with 54 blades
 * fueltype= Fuel type, for example aviation kerosene with 1% lubricating oil
 * oilsystem= Description of the oil system, US gal (L) capacity, oil circulation rate US gal/h (L/h), maximum inverted flying time, etc.
 * power= Power (for gas-turbine engines), shp (kW)
 * thrust= Thrust, lbf (kN) at # rpm, specify if afterburning or non-afterburning.
 * compression= Overall pressure ratio, #:1
 * bypass= Bypass ratio
 * aircon= Air consumption, lb/s (kg/s)
 * turbinetemp= Turbine inlet temperature, °F (°C)
 * fuelcon= Fuel consumption, US gal/h (L/h) or lb/h (kg/h)
 * specfuelcon= Specific fuel consumption lb/(lbf·h) (kg/(kN·h))
 * thrust/weight= Thrust-to-weight ratio, calculated by dividing engine thrust by engine weight, lbf thrust divided by lb weight is unitless. Metric kN/kg is the same except multiplied by 9.8.
 * Power/weight= Power-to-weight ratio (for gas-turbine engines), calculated by dividing engine power by engine weight, shp/lb (kW/kg)