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35-515: Development of the CitationJet was prompted by the 1985 discontinuation of the Citation I , a reaction to the increasing price of its Pratt & Whitney JT15D-1 engines, which rendered it uncompetitive with its larger straight wing Citation stablemates. Cessna believed that a substantial market still existed for a light 4-5 passenger jet with low operating costs, docile flying qualities, and

70-462: A pressurized cabin . The jet uses the Citation II's forward fuselage, a new carry-through section, a new laminar flow , supercritical wing developed with NASA and Boeing , and a T-tail . Powered by two 1,900 lbf (8.5 kN) Williams FJ44s , the 10,000 lb (4,500 kg) aircraft has a trailing link undercarriage for smooth landings, and can be flown by a single pilot. Range

105-646: A competitive challenge in the form of two newly-developed light business jets , the Learjet 23 and the Aero Commander 1121 Jet Commander , which were much less expensive to buy and operate than previous business jets such as the North American Sabreliner and Hawker Siddeley HS.125 . Previous efforts by Beechcraft and Cessna to market small jets had not met with success: the Cessna 407 ,

140-464: A demand for 1,000 aircraft over ten years. Its first flight was on April 29, 1991, a Federal Aviation Administration (FAA) type certificate was awarded on October 16, 1992, and first delivery happened on March 30, 1993. The aircraft met its initial design goal: its normal cruise speed was 29 kn (33 mph; 54 km/h) faster than that of the Citation I, and the newer CitationJet outperformed

175-399: A large fairing encases the low wing center section, and the engines are mounted high on the tail. Composite materials save weight in non-load-bearing components including fairings and the nose radome . The cockpit features EFIS avionics; fuselage length is reduced 11 inches (27 cm) compared to the Citation I, and cabin length is reduced by 1 ft 6 in (46 cm), but with

210-434: A lowered center aisle for increased cabin height. The cockpit side windows are slightly smaller than those on earlier Citations to lessen interior temperature differences between the cockpit and the main cabin. Wing structure is a conventional ladder with chord-wise ribs over front and rear spars, and an aft sub spar to support the landing gear. The NASA high-speed 0213 airfoil sustains natural laminar flow over 30% of

245-530: A new, lighter airframe design would be needed, using less expensive and lower-thrust engines. To better compete with newer jets, Cessna also wanted to eliminate the step in the center aisle of the earlier Citations, created by the spar passing through the cabin. Cessna launched the $ 2.4 million (equivalent to $ 5.9 million in 2023) model 525 CitationJet at the October 1989 NBAA convention in Atlanta, estimating

280-595: A novel design feature to reduce weight: rather than conventional thrust reversers , the aircraft are equipped with thrust attenuator paddles that pivot from the rear fuselage, similar to those used on the Cessna T-37 Tweet military trainer. The ICAO aircraft type designator for the CJ2 models is C25A. The ICAO aircraft type designator for the CJ3 models is C25B. The ICAO aircraft type designator for

315-736: A proposed civil version of the T-37 Tweet jet trainer, had not proceeded past the mockup stage due to insufficient customer interest, while an effort by Beechcraft to market the Morane-Saulnier MS.760 Paris in North America had ended with only two aircraft sold. However, the runaway success of the Learjet caused the two companies—which only manufactured piston engined aircraft at the time—to reconsider turbine engined aircraft, and Beechcraft launched two simultaneous efforts:

350-406: Is 1,500 nmi (2,800 km) with four passengers and it can cruise at 437 kn (503 mph; 809 km/h). The CitationJet retains the 58 in (147 cm) inside diameter, circular fuselage cross-section of the Citation I and II, a semi-monocoque construction of conventional aluminum alloys assembled with rivets , fasteners and adhesive bonding . To reduce interference drag ,

385-413: Is a very thin sheet of air lying over the surface of the wing (and all other surfaces of the aircraft). Because air has viscosity , this layer of air tends to adhere to the wing. As the wing moves forward through the air, the boundary layer at first flows smoothly over the streamlined shape of the airfoil . Here, the flow is laminar and the boundary layer is a laminar layer. Prandtl applied the concept of

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420-412: Is characterized by eddies or small packets of fluid particles, which result in lateral mixing. In non-scientific terms, laminar flow is smooth , while turbulent flow is rough . The type of flow occurring in a fluid in a channel is important in fluid-dynamics problems and subsequently affects heat and mass transfer in fluid systems. The dimensionless Reynolds number is an important parameter in

455-427: Is in the smooth flow of a viscous liquid through a tube or pipe. In that case, the velocity of flow varies from zero at the walls to a maximum along the cross-sectional centre of the vessel. The flow profile of laminar flow in a tube can be calculated by dividing the flow into thin cylindrical elements and applying the viscous force to them. Another example is the flow of air over an aircraft wing . The boundary layer

490-412: Is the property of fluid particles in fluid dynamics to follow smooth paths in layers, with each layer moving smoothly past the adjacent layers with little or no mixing. At low velocities, the fluid tends to flow without lateral mixing, and adjacent layers slide past one another smoothly. There are no cross-currents perpendicular to the direction of flow, nor eddies or swirls of fluids. In laminar flow,

525-556: The "Nearjet" vulnerable to "bird strikes from the rear"; Cessna renamed it the " Citation " after the thoroughbred but it was nicknamed as "Slowtation". Notable accidents and incidents involving the Citation 500, Citation I and Citation I/SP: Data from Jane's Civil and Military Aircraft Upgrades 1994-95 General characteristics Performance (above 28,000 ft (8,500 m) Related development Aircraft of comparable role, configuration, and era Laminar flow Laminar flow ( / ˈ l æ m ɪ n ər / )

560-466: The CJ4 models is C25C. Related development Aircraft of comparable role, configuration, and era Related lists Citation I The Cessna 500 Citation I is a small business jet produced by Cessna , the basis of the Citation family . The Fanjet 500 prototype was announced in October 1968, first flew on September 15, 1969, and was certified as the 500 Citation on September 9, 1971. It

595-499: The Learjet, which were far faster but also relatively unforgiving to fly, requiring highly skilled pilots and long runways. Cessna reasoned that a market existed for a light jet that was faster than the King Air but similarly easy to fly, relatively inexpensive to buy and maintain, and able to access small airports with shorter runways. This type of aircraft would appeal to traditional Cessna buyers: amateur owner-pilots who intend to fly

630-481: The Reynolds number increases, such as by increasing the flow rate of the fluid, the flow will transition from laminar to turbulent flow at a specific range of Reynolds numbers, the laminar–turbulent transition range depending on small disturbance levels in the fluid or imperfections in the flow system. If the Reynolds number is very small, much less than 1, then the fluid will exhibit Stokes , or creeping, flow, where

665-547: The ability to operate from short runways usable by twin piston -engined light aircraft , a formula that had made the Citation I successful. However, that aircraft had been stigmatized for its slower cruise speed than its competitors, which had progressively been addressed in the Citation S/II and Bravo and the Citation V, Ultra and Encore , but at the cost of operating economy. To offer increased speed with reduced purchase and operating costs, Cessna engineers realized that

700-429: The aircraft themselves. In October 1968 Cessna announced an eight place business jet capable of operating from airfields accessible to light twins. The Fanjet 500 prototype first flew on September 15, 1969. By then its unit cost was $ 695,000, $ 5.77M today. The renamed 500 Citation had a relatively long development program with a longer forward fuselage, repositioned engine nacelles, a larger tail and more dihedral to

735-473: The development of the turboprop -powered King Air 90 and an agreement to market the HS.125 in North America. Cessna quickly found that its premium twin piston-engine aircraft were uncompetitive with the King Air, which was substantially faster, yet could be flown by pilots with similar skills and licensing qualifications. However, the company also saw a broad gap between the King Air and existing light jets such as

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770-401: The equations that describe whether fully developed flow conditions lead to laminar or turbulent flow. The Reynolds number is the ratio of the inertial force to the shearing force of the fluid: how fast the fluid is moving relative to how viscous it is, irrespective of the scale of the fluid system. Laminar flow generally occurs when the fluid is moving slowly or the fluid is very viscous. As

805-459: The fluid: laminar flow or turbulent flow . Laminar flow occurs at lower velocities, below a threshold at which the flow becomes turbulent. The threshold velocity is determined by a dimensionless parameter characterizing the flow called the Reynolds number , which also depends on the viscosity and density of the fluid and dimensions of the channel. Turbulent flow is a less orderly flow regime that

840-434: The horizontal tail. It was FAA certified on September 9, 1971. In 1974, thrust reversers became optional, and in 1976, the gross weight was increased by 1,000 pounds (450 kg) to 10,850 pounds (4,920 kg). In early 1976, the wingspan was increased from 43.9 to 47.1 ft (13.4 to 14.4 m). The enhanced 500 Citation I was introduced later in 1976 with the higher gross weight, improved JT15D -1A engines and

875-415: The increased span wing. Speed and range were enhanced, the aircraft's service ceiling increased from 35,000 to 41,000 feet (11,000 to 12,000 m), and the cabin pressure at altitude was increased from 7.6 to 8.6 psi (52 to 59 kPa). Many of the original Citations, of which 349 were produced, were upgraded with the new engines. The 501 Citation I/SP , certificated for single pilot operations,

910-404: The laminar boundary layer to airfoils in 1904. An everyday example is the slow, smooth and optically transparent flow of shallow water over a smooth barrier. When water leaves a tap without an aerator with little force, it first exhibits laminar flow, but as acceleration by the force of gravity immediately sets in, the Reynolds number of the flow increases with speed, and the laminar flow of

945-554: The larger and faster II and II/SP. By 2018, used 1970s model 500s were valued at $ 300,000, Citation ISPs at $ 695,000 to $ 1.25 million with the Eagle II package. The aircraft was powered by two Pratt & Whitney Canada JT15D -1 turbofan engines after Cessna's experience with the T-37 Tweet twinjet trainer. Its use of turbofans rather than turbojets and straight wings rather than swept wings made it cruise slowly compared to other business jets and Learjet salesmen mocked it as

980-429: The motion of the particles of the fluid is very orderly with particles close to a solid surface moving in straight lines parallel to that surface. Laminar flow is a flow regime characterized by high momentum diffusion and low momentum convection . When a fluid is flowing through a closed channel such as a pipe or between two flat plates, either of two types of flow may occur depending on the velocity and viscosity of

1015-435: The older Citation I in all other significant metrics except maximum payload and approach noise, despite having 600 lbf (2.7 kN) less total engine thrust. Twenty years after its first flight, 1,450 CJs had been produced. As of June 2017, 2,000 of all variants had been delivered, with five million hours flown. The six-seat CitationJet is a monoplane with a cantilever wing , a retractable tricycle landing gear and

1050-593: The transition range is typically between 1,800 and 2,100. For fluid systems occurring on external surfaces, such as flow past objects suspended in the fluid, other definitions for Reynolds numbers can be used to predict the type of flow around the object. The particle Reynolds number Re p would be used for particle suspended in flowing fluids, for example. As with flow in pipes, laminar flow typically occurs with lower Reynolds numbers, while turbulent flow and related phenomena, such as vortex shedding , occur with higher Reynolds numbers. A common application of laminar flow

1085-433: The upper surface for 10-15% better lift-to-drag ratio than the larger NACA 23000 -series wing of the Citation I. To maintain the wing's laminar-flow qualities and reduce weight, icing protection is provided by ducted bleed air rather than the deicing boots or fluid deicing systems used on earlier Citations. Its FJ44 engine has a 16:1 overall pressure ratio and a 2.58:1 bypass ratio . Early CitationJet models have

Cessna CitationJet/M2 - Misplaced Pages Continue

1120-435: The viscous forces of the fluid dominate the inertial forces. The specific calculation of the Reynolds number, and the values where laminar flow occurs, will depend on the geometry of the flow system and flow pattern. The common example is flow through a pipe , where the Reynolds number is defined as where: For such systems, laminar flow occurs when the Reynolds number is below a critical value of approximately 2,040, though

1155-504: The water downstream from the tap can transition to turbulent flow. Optical transparency is then reduced or lost entirely. Laminar airflow is used to separate volumes of air, or prevent airborne contaminants from entering an area. Laminar flow hoods are used to exclude contaminants from sensitive processes in science, electronics and medicine. Air curtains are frequently used in commercial settings to keep heated or refrigerated air from passing through doorways. A laminar flow reactor (LFR)

1190-495: Was delivered in early 1977. Production ended in 1985, it was developed into the Citation II /Bravo and the Citation V /Ultra/Encore. 395 Citations and Citation Is and 296 I/SPs were built between 1971 and 1985. The aircraft were dropped from production because JT15D engine prices had increased to the point that the price difference between the Citation I and Citation II series had become minimal, causing most buyers to opt for

1225-410: Was upgraded in 1976 as the Citation I , and the 501 Citation I/SP single-pilot variant was introduced in 1977. Production ended in 1985 with 689 of all variants produced. The straight wing jet is powered by JT15D turbofans. The aircraft was developed into the Citation II . In the early 1960s, the three major American general aviation aircraft manufacturers— Beechcraft , Cessna and Piper –faced

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