{{short description|1950s American ramjet engine}} {{Multiple issues|{{more citations needed|date=November 2018}}{{More footnotes|date=October 2018}}}} {{Use dmy dates|date=October 2018}} {{infobox aero engine |name= XRJ47 |image= |caption= |engine_type= [[Ramjet]] |national_origin = United States |manufacturer= [[Wright Aeronautical]] |first_run= |major_applications= |number_built = |developed_from = |developed_into = }}
The '''Wright XRJ47''' was an American ramjet engine developed in the 1950s to help propel the rocket-launched [[SM-64 Navaho]] supersonic intercontinental cruise missile. Although the design flight Mach Number was 2.75, a peak flight speed of Mach 3.0, at altitudes up to about 77,000 ft, was envisaged. This very large ramjet had a number of design problems, including some difficulty in light-up. Development of the Navaho missile was cancelled along with the ramjet engine in 1957.
==Design== The single cone supersonic intake supplied ram air to a long annular diffuser terminating at the aft-mounted cylindrical combustion chamber. The centreline of the intake system was gently curved, presumably to line up the intake face with the flow-field of the missile nose section.
The combustion chamber flame-holder consisted of a center-body pilot region, with three annular V-gutters interconnected by slanted radial V-gutters. Fuel jets were of variable area design.
A heat-shield, with multiple exit ports, provided cooling air for the jetpipe and the fixed area ratio convergent-divergent propelling nozzle. The exit diameter of the nozzle equaled that of the combustion chamber.
==Specifications (XRJ47-W-5)== {{jetspecs <!-- 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> --> |ref=Aircraft Engine Characteristics Summary: Ram-jet XRJ47-W-5,<ref name=avialog>{{cite book |title=Aircraft Engine Characteristics Summary: Ram-jet XRJ47-W-5 |year=1957 |publisher=www.avialogs.com |url=https://www.avialogs.com/engines-w/wright/item/7729-xrj47-w-5-ramjet-aircraft-engine-characteristics-summary-1-april-1957}}</ref> Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75<ref name=NACA>{{cite book |last1=Welna |first1=Henry J. |last2=Reilly |first2=Dwight H. |title=Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75 |url=https://digital.library.unt.edu/ark:/67531/metadc53082/m2/1/high_res_d/19660027126.pdf |year=1955 |publisher=Lewis Flight Propulsion Laboratory, Cleveland, Ohio}}</ref> |type= Ramjet |length= {{cvt|390|in}} combustion chamber plus ducting and diffuser |diameter= {{cvt|48|in}} (combustion chamber) *'''Intake lip area:''' {{cvt|636|sqin}} *'''Combustion chamber area:''' {{cvt|1810|sqin}} *'''Nozzle throat geometric area:''' {{cvt|1182|sqin}} *'''Nozzle exit geometric area:''' {{cvt|1810|sqin}} |weight={{cvt|1011|lb}} |compressor= Ramjet inlet/diffuser |combustion=approx {{cvt|1887|K|F C}} *'''Combustion efficiency:''' 83.3% * '''Burn time:''' 6500 s |turbine= |fueltype= [[JP-5]] (F-44 / AVCAT) |oilsystem= |power= |thrust= {{cvt|3792|lbf|kN}} |compression= |aircon={{cvt|59.8|lb/s|kg/s}} |turbinetemp= |fuelcon={{cvt|10548|lb/h|kg/h}} |specfuelcon={{cvt|2.782|lb/lbf/h|kg/kN/h}} |thrust/weight=3.75 }}
==References== {{reflist}}
==Further reading== *{{cite book|last=Arrighi|first=Robert S.|title=Bringing the Future Within Reach: Celebrating 75 Years of the NASA|year=2016|publisher=NASA}}
{{Wright/Lawrance aeroengines}} {{US military ramjet aeroengines}}
[[Category:Ramjet engines]]