Here’s a Cessna Citation X rocketing out of Addison Airport in North Dallas. The aerodynamics and the engine power allow the Citation X at maximum takeoff weight to climb straight to 43000 feet in only 20 minutes. During its flight test program, the Citation X easily reached Mach 0.98 in level flight but its maximum cruise speed to still have favorable operating efficiency is Mach 0.92 which, taking altitude into account, makes it 200 knots faster than the original Citation I. Through the use of high end computational fluid dynamics, the aerodynamics of the Citation X give it the same operating costs at Mach 0.92 as competitor’s jets that are much slower- and this is really what makes the Citation X so remarkable- cruising at transonic speeds can be incredibly inefficient due to the rise in drag. ~ Much like how supersonic fighter jets of the 1960s had “coke-bottle” waists at mid-fuselage for area-ruling to allow supersonic flight, area-ruling for the Citation X instead took the form of the long under fuselage fairing that extends from just behind the nose gear to under the wings to near the tail. This long fairing isn’t there for looks though it sure doesn’t hurt- to delay the onset of transonic drag, the key is to allow the air moving over part of the aircraft to accelerate slowly and decelerate slowly as it passes certain points on the airframe. The long underfuselage fairing slows the acceleration of the local airflow under the fuselage and then slows its deceleration as it passes the the center fuselage. ~ The sharp wing sweep back and supercritical airfoil allow for a thicker wing than what would be possible at a lesser wing sweep. This allowed for generous wing fuel tanks- the Citation X’s wing carries fuel all the way across except the most outboard 18 inches of each wing. ~ #avgeek #aviation #aircraft #planeporn #KADS #ADS #Addison #airport #planespotting #instaplane #instagramaviation #Avgeekery #Cessna #Citation #CitationX #N750DD #splendid_transport #instaaviation #aviationlovers #aviationphotography #flight #AvgeekSchoolofKnowledge #AvGeek_SchoolofKnowledge (at Dallas Love Field)
