lockheed lockheed single engine high performance prototype united_states_air_force series lightweight simple fighters aircraft built aircraft primarily aerodynamic research served armament prototypes destroyed accidents testing forerunner lockheed korean war fighter pilots equipped soviet pilots lockheed engineers led designed submitted novel design air_force design notable particularly thin wings missile shaped fuselage novel pilot system maiden flight came february flight test program encountered problems resolved performance proved better estimates prototypes lost accidents ordered service test internationally production proved popular serving line fighters number countries development chief engineer lockheed visited korea december talked fighter pilots sort aircraft wanted time pilots confronting north american pilots felt superior larger complex american design pilots requested small simple aircraft excellent performance pilot particular colonel quoted saying sight piece stuck told johnson radar waste time return johnson immediately started design aircraft realising official requirement soon published march team assembled different aircraft proposals ranging small designs fairly large ones design known remained essentially identical model eventually delivered design presented air_force november interested create new proposal inviting companies participate additional designs received improved version prototype north american eventually evolve new powered design interesting lockheed lead granted development contract march test data earlier lockheed rocket program proved aerodynamic research share general design wing tail experience gained douglas design phase surplus artillery rockets launched test tail designs camera film recovered parachute wooden mock ready inspection end april work started prototypes late engine ready prototypes instead designed use wright licensed built version construction prototype serial number buzz number began summer lockheed burbank california factory aircraft powered non built wright prototype completed early started flying march total time award contract flight year short time today years typical construction second prototype proceeded slower pace design order achieve desired performance lockheed chose minimalist approach design achieve high performance wrapping efficient airframe possible single powerful engine emphasis drag mass radical wing design jets use swept delta wing allows reasonable balance aerodynamic performance lift internal space fuel equipment efficient shape high speed flight found small straight mid mounted wing low aspect ratio high wing loading wing extremely thin thickness chord ratio leading edges wing thin sharp presented hazard ground crews protective guards installed ground operations wings meant fuel tanks landing gear contained fuselage hydraulic driving inch thick fit available space known resemblance musical instrument wings electrically driven leading trailing edge flaps increase lift low speed feature production aircraft extensive wind tunnel testing mounted fin stability control pitch axis vertical tail fin slightly shorter length wing nearly effective act wing rudder application phenomenon known dutch roll offset effect wings angled downward rudder manually operated supplemented small surface mounted fin fuselage high ratio tapering sharply nose small frontal area fuselage tightly packed containing cockpit cannon internal fuel landing gear engine air designed fixed geometry inlet powered aircraft incapable performance similar mounted slightly away fuselage inner plate boundary layer bleed air combination features provided extremely low drag high angle attack point induced drag high featured unusual downward stanley seat feared contemporary seat designs explosive power clear high tail assembly event seat firing possible manually release lower fuselage hatch exit aircraft gravity series aircraft later convert upward seats fuselage hatch retained useful maintenance feature operational history testing evaluation lockheed transported edwards amidst high secrecy night february lockheed test pilot initial testing february planned hop ground high speed taxi official flight took place march flight landing gear landed low speed flight minutes adjustments flights discovered problem low pressure hydraulic system bad weather kept ground march flights carried landing gear normally second prototype lockheed fitted start flew october armament test bed fitted vulcan cannon equipped fire control system achieved speed feet march piloted lockheed test pilot highest speed achieved level flight powered non easily exceeded slight descent july replaced engine installed performance greatly improved maximum level speed altitude attained climb attained dive accepted november initial aerial firing tests vulcan cannon second aircraft successful december explosion firing burst engine suffered severe stalls immediately shut engine successful landing investigation later showed cannon rounds exploded breech blowing bolt rear gun structure forward fuselage fuel cell jet fuel run gun bay leaked compartment door seals left engine air intake engine immediately flooded fuel causing stalls crashes lost crash july developed tail flying chase flight tests entire tail group ripped airframe lockheed test pilot forced vertical fin known problem aircraft limited speeds time accident attempted aircraft removed flight status placed museum arguing performance suitable chase duties lost april accumulating flying hours test pilot forced gun firing trials gun test firing severe vibrations began build knocked loose hatch cockpit cabin pressure lost salmon pressure suit covering face recalling experience exploding cannon shell previous december salmon believed thing happened option later found saved simply bringing lower altitude waiting pressure suit loss armament lockheed engineers forced find alternative armament trials continued modified amassed approximate total flight hours testing conclusions flight testing proved performance estimates accurate fitted low powered engine flew faster century series fighters developed time ceiling higher predicted exceeded estimated speed drag figures percent noted low thrust engine enable performance potential type realized number minor problems surfaced readily fixed found ineffective rudder positively center problems corrected rudder control system rudder provide adequate directional control high air speeds hydraulic power subsequent versions concern expressed poor higher altitudes later interview asked opinion aircraft come designs terms performance yes terms engine went great engine problems designing airframe johnson jointly awarded trophy sharing honor general_electric engine flight records production official approval design led contract service test aircraft production run aircraft built united_states license worldwide visible changes production versions include longer fuselage accommodate engine extra internal fuel forward nose landing gear seat versions increase clearance downward seat ventral fin increased stability added test program inlet shock fuselage spine canopy fin housed fuel added features production aircraft feature redesigned fin structure steel eliminate problem internal fuel capacity low limiting useful range aircraft extra capacity provided later versions forward fuselage specifications data characteristics crew length wingspan height wing area convex weight loaded weight max takeoff weight powerplant wright dry thrust lbf thrust lbf performance maximum speed mph stall speed mph range nmi service ceiling armament guns vulcan cannon
Lockheed XF-104