注册 登录  
 加关注
   显示下一条  |  关闭
温馨提示!由于新浪微博认证机制调整,您的新浪微博帐号绑定已过期,请重新绑定!立即重新绑定新浪微博》  |  关闭

中庸半才

竞争是对手,胜负是朋友!

 
 
 

日志

 
 

[中庸精品]YF-23A.  

2008-04-08 11:19:56|  分类: 中庸军事图鉴 |  标签: |举报 |字号 订阅

  下载LOFTER 我的照片书  |
  

  

  

  

  

  

  

  In1981,theAirForcedevelopedarequirementforanAdvancedTacticalFighter(ATF)asanewairsuperiorityfighter.Itwouldtakeadvantageofthenewtechnologiesinfighterdesignonthehorizonincludingcompositematerials,lightweightalloys,advancedflightcontrolsystems,higherpowerpropulsionsystems,andstealthtechnology.AirForceleadersbelievedthesenewtechnologieswouldmakeaircraftliketheF-15andF-16obsoletebytheearly21stcentury.In1985,theAirForcesentouttechnicalrequestsforproposalstoanumberofaircraftmanufacturingteams(Boeing/GeneralDynamicsandNorthrop/McDonnellDouglas).

  TheAdvancedTacticalFighter(ATF)projectwasconceivedintheearlyyearsofReaganadministration.ItwaspicturedasbeingtheaircraftwhichwouldreplacetheMcDonnellDouglasF-15EagleinUSAFservice.ThecompetitorwereLockheedwithit'sYF-22andNorthrop/McDonnelDouglaswithit'sYF-23.

  ThebodyoftheYF-23Aisablendofstealthyshapesandaerodynamicefficiency,hopefullyprovidingalowradarcrosssectionwithoutcompromisingperformance.TheYF-23AwaslongerandmoreslenderthantheLockheedYF-22A.Themainload-bearingfuselagestructure,measuredfromthestablizertothefrontofthecockpit,isabout7feetlongerthantheYF-22A.Fromtheside,theprofileoftheYF-23AisreminiscentofthatoftheLockheedSR-71.Thegeneralimpressionfromotheranglesisthatofalong,highforebodymountedbetweentwowidely-separatedenginenacelles.Thelengthwisevariationincross-sectionalareaisverysmooth,minimizingtransonicandsupersonicdrag.Theforwardsectionhasamodifieddouble-trapezoidcrosssection,oneabovetheotherinmirrorimage,withtheaftregionblendingintoacircularcrosssectionanddisappearingintotherearfuselage.Theuppercomponentoftheengineboxisdominatedbytwoparallelenginenacellesthatblendsmoothlyintothewing,eachnacellebeingofamodifiedtrapezoidalcrosssection.Theforebodyhasthecockpit,thenoselandinggear,theelectronics,andthemissilebay.TheYF-23enginenacelleswerelargerthantheywouldhavebeenontheproductionF-23,sincetheyhadbeendesignedtoaccommodatethethrustreversersoriginallyplannedfortheATFbutlaterdeleted.

  Trapezoid-shapedairinletsarelocatedunderneatheachwing,withtheleadingedgeformingtheforwardlipofasimplefixed-geometrytwo-shocksystem.Theplacementoftheintakesunderneaththewingshastheadvantageinremovingthemfromthesidesofthefuselagesothatalargeboundary-layerscoopisnotneeded.Instead,thethinboundarylayerwhichformsonthewingaheadoftheinletisremovedthroughaporouspanelandisventedabovethewing.Anauxiliaryblow-ininletdoorislocatedoneachoftheuppernacellesjustaheadoftheenginetoprovideadditionalairtotheenginesfortakeofforforlowspeeds.Theinletductsleadingtotheenginescurveintwodimensions,upwardandinward,toshieldthefacesofthecompressorsfromradaremitterscomingfromtheforwarddirection.

  TheleadingedgeoftheYF-23A'swingissweptbackat40degrees,andthetrailingedgeissweptforwardatthesameangle.Whenviewedfromabove,thewinghastheplanformofaclippedtriangle.OntheYF-23A,everylineintheplanformisparalleltooneortheotherofthewingleadingedges,whichhasbecomeoneoftheguidingprinciplesinstealthydesign.Thewingisstructurallydeep,andthereisampleroomforfuelinsidethewingbox.

  Thewinghasleading-edgeslatswhichextendoverabouttwo-thirdsofthespan.Thetrailingedgehasasetofflapsinboardandasetofdroopingaileronsoutboard.IncontrasttotheLockheedYF-22A,nospeedbrakeisfittedtotheYF-23A.

  Theall-flyingtwinV-tailsaresetfarapartontherearfuselage.Theyarecanted50degreesoutwardsinanattempttoavoidacutecornersorrightanglesinelevationorfrontview.Theseall-flyingtailsectionsarehingedatasinglepivot.Theirleadingandtrailingedgesareparalleltothemainwingsbutinadifferentplane.Theall-flyingcantedtailsdoubleasshieldsfortheengineexhaustinallanglesexceptthoseimmediatelyaboveorhehindtheaircraft.

  IntheYF-23A,Northropelectednottousethrust-vectoringforaerodynamiccontrol.Thiswasdoneinordertosaveweightandtohelpachievebetterall-aspectstealth,especiallyfromtherear.Allcontrolsarebyaerodynamicsurfaces.TheV-tailsworkinpitch,roll,andyaw.Thewingtrailingedgecontrolsproviderollcontrolandliftaugmentation,buttheyalsofunctionasspeedbrakesandrudders.Forstraightlinedeceleration,thecontrolsystemcommandstheouteraileronstodeflectupandtheinboardflapstodeflectdown,thusproducingadeceleratingforcebutcreatingnoothermoments.Yawcontrolcanbeprovidedbydoingthisononesideonly.

  Thereisamidairrefuellingreceptaclelocatedontheupperfuselagebehindthepilot'scockpit.LiketheYF-22A,theYF-23Ahasafly-by-wiresystemthatcontrolsthesettingsoftheaerodynamicsurfacesinresponsetoinputsfromthepilot.

  Theedgetreatmentissustainedonthefuselageafterbody,whereajagged-edgedboat-taildeckfillsinthegapbetweenthetwoV-tailsandblendstheengineexhaustsintothelow-RCSplanform.UnliketheYF-22A,theYF-23Adoesnotusethrustvectoring.Theexhaustnozzlesarelocatedwellforwardontheupperfuselage,betweenthetails,andareofthesingleexpansionramptype.Thereisonevariableexternalflapontopofeachnozzle,andthelowerhalfofeachnozzleisfairedintoacurved,fixedramp.Theenginesexhaustintotunnelsortrenchescutintotherearfuselagedecking.Thesetrenchesarelinedwithhead-resistantmaterial,coolingtheengineexhaustrapidlyandmakingforaweakerIRsource.

  Inthepursuitofstealth,alloftheweaponscarriedbytheF-23weretohavebeenhousedcompletelyinternally.Theforwardsectionofthefuselageunderbellywasflat,withacapaciousweaponsbayimmediatelyaftofthenosegearbay.ThebaycouldcarryfourAIM-120AMRAAMair-to-airmissiles.Themissilesweretobelaunchedbyhavingthedoorsopenandthemissilesextendoutintotheairstreamontrapezes.Themissileswouldthendropfreeandthemotorwouldfire.Thedoorswouldthenimmediatelyshut,minimizingtheamountoftimethattheywereopenandthuspossiblycausingmoreintenseradarreturns.ItwasplannedthatproductionF-23wouldhavehadastretchedforebody,accommodatinganextramissilebayforapairofAIM-9SidewindersorASRAAMair-to-airmissilesinfrontoftheAMRAAMbay.Inaddition,productionF-23swouldhavecarrieda20-mmM61Vulcancannonfittedinsidetheupperstarboardfuselagejustabovethemainweaponsbay.

  LiketheYF-22team,theNorthropteambuilttwoYF-23prototypes,onewithGeneralElectricYF-120

  enginesandtheotherwithPratt&WhitneyYF-119engines.Firsttakeoffof"GrayGhost"27thAug1990onEdwardAFB,26thOct1990secondprototype.Firstprogrammdurated65hoursdividedinto50flights,endedbysecondprototype18thDec1990.Afterextensiveflighttesting23thApr1991theYF-22was

  selectedforproduction.

  Locationofbothplanes:EdwardsAFB-California.

  TYPE:YF-23

  Numberbuilt/Converted:2(PAV-1(87-800),PAV-2(87-801))

  Remarks:ATF;losttoYF-22

  SPECIFICATIONS

  Span:43ft.7in.(13,2m)

  Length:67ft.5in.(20,3m)

  Height:13ft.11in.(4,2m)

  Wingarea:87,7m2

  Weight:54,000lbs.(23,500kg)takeoff(YF-23/ATFdesignspec).

  Emptyweight:38,580lbs(16,783kg).

  Internalfuel:2190lbs(952kg)

  Engines:TwoPratt&WhitneyF119-PW-100's(87-800)ofapproximately35,000lbs.thrusteachwithafterburnerandtwoGeneralElectricF120-GE-100(87-801)turbofans.EnginecompetitionwonbyPratt&Whitney.

  Crew:One

  Maximumspeed:approximatelyMach2.0

  SpeedwithoutafterburnerMach1.6

  ServiceCeiling:approximately65,000ft.(ATFdesignspec)

  Range:1200km

  Armament:(planned)

  Internalgun20mmM61

  Internalbay-8xAIM-9Sidewinderor4xAIM-120AMRAAM;A-Gmissiles"HaveDash2",A-Gmissiles"HaveSlick"

  

  

  

  
  评论这张
 
阅读(163)| 评论(8)
推荐 转载

历史上的今天

评论

<#--最新日志,群博日志--> <#--推荐日志--> <#--引用记录--> <#--博主推荐--> <#--随机阅读--> <#--首页推荐--> <#--历史上的今天--> <#--被推荐日志--> <#--上一篇,下一篇--> <#-- 热度 --> <#-- 网易新闻广告 --> <#--右边模块结构--> <#--评论模块结构--> <#--引用模块结构--> <#--博主发起的投票-->
 
 
 
 
 
 
 
 
 
 
 
 
 
 

页脚

网易公司版权所有 ©1997-2017