The Cessna Citation I and II are small business Jet transports in the same weight class as the Gates Learjet. Low first costs, economy of operation, safety, and viceless handling characteristics were among the design objectives. In order to provide wide operational flexibility, the aircraft was designed to take off and land from most fields used by light and medium twin-engine propeller-driven aircraft, and from unpaved runways. First flight took place in September 1969, and the aircraft was certified in September 1971.
Cessna delivered the first Citation in 1972. In 1976 the company announced three new business jets: the improved Citation I; the larger, better-performing Citation II; and the Citation III. The Citation III was the first all-new business jet designed and produced in the United States since the original Citation in 1972.
That the Citation I and II have been widely accepted is clearly demonstrated by the more than 1000 aircraft that have been produced; the will likely continue to find a significant share of the business jet market for a number of years. Although the Citation I and II are similar in appearance, the Citation II is somewhat larger and heavier than the Citation I and has a longer range capability.
The Citation II has an unswept wing, an aspect ratio of 8.3, and airfoil-section thickness ratios that vary from 14 percent at the root to 12 percent at the tip. The horizontal tall is located near the root of the vertical fin and incorporates a small amount of dihedral to reduce immersion in the jet exhaust. To improve directional stability, the vertical tall has a relatively large dorsal fin together with a small ventral fin. Power is supplied by two Pratt & Whitney JTI 5D-4 turbofan engines of 2500 pounds thrust each and bypass ratio of 3.3.
The high-lift system on both versions of the Citation consists of a single-slotted trailing-edge flap; no leading-edge devices are employed. Spoilers located on the upper wing surface ahead of the flap are used as air brakes and are not part of the lateral control system, which utilizes only ailerons. Longitudinal control is by elevators, and trim is obtained by an electrically operated trim tab on the elevator. All controls re manually operated.
The Citation II has a gross weight of 13 300 pounds and a cabin hat is usually configured to carry from 6 to 10 passengers. With six passengers, the aircraft has a range of 1969 miles. Normal cruising speed is 443 miles per hour, which corresponds to a Mach number of .64 at 25 000 feet; maximum operating speed is 485 miles per hour at 25 000 feet, which gives a Mach number of 0.70. The stalling speed of 94 miles per hour is the lowest of any of the aircraft listed in table VIII. This low stalling speed is obtained with a relatively simple highlift system because the wing loading is only about 41 pounds per square foot. This low wing loading together with the high thrust-to-weight ratio of 0.38 are responsible for the short takeoff distance given in the table.
To complement the highly successful Citation I and II line of business jets, Cessna is now producing an entirely new aircraft of higher performance, the Citation III. First flight of this aircraft took place in May 1979, and first deliveries were scheduled for 1983. As can be seen from Figure 14.9, the Citation III bears no resemblance to the earlier Citation I or Citation II. Instead of a straight wing, the new aircraft has a 25 sweptback wing of 9.11 aspect ratio. Incorporated in the wing are NASA supercritical-type airfoil sections that vary in thickness ratio from 16 percent at the root to 12 percent at the tip. The high-lift system consists of trailing-edge slotted flaps; lateral control is provided by spoilers and small ailerons.
In contrast to earlier Citations, the Citation III employs a T-tail. The aircraft is powered by two AiResearch TFE 731-3 turbofan engines of 3650 pounds thrust each and 2.79 bypass ratio. To assist in braking on landing rollout, the engines are equipped with hydraulically actuated thrust reversers. The gross weight of the Citation III is in the same class as that of the Gates Learjet 55. The aircraft has a maximum passenger capacity of 13 and is capable of carrying 6 passengers (plus 2 pilots) over a nonstop United States coast-to-coast range of 2875 miles. Maximum cruising speed is 539 miles per hour at 33 000 feet (M = 0.8 1), and maximum certified cruising altitude is 51 000 feet. Stalling speed is a relatively low 104 miles per hour and results from a combination of low wing loading, good high-lift flaps, and high maximum-lift characteristics of the blunt leading-edge supercritical airfoil sections. The Citation III was a worthy stablemate to the highly successful Citation I and II aircraft.
The Citation II was replaced in 1984 by the improved Citation S-550 (S/II).
In 1994 Cessna introduced the Citation Bravo, a replacement for the Citation II. Completing certification in 1996, the Bravo incorporates improvements including upgraded avionics, trailing link landing gear, more speed, range and payload. Deliveries began in February 1997. In October 1994 Cessna announced the Citation Excel, a light jet that offers a stand-up cabin. The Excel was certified in 1998 and deliveries began in July 1998.
In September 1987, Cessna introduced the Citation 560 / Citation V, a larger and faster aircraft than the the previous Citation II and SII. Deliveries began early in 1989. Since its introduction, the Citation V has been the world's fastest-selling business jet. The aircraft has a range of 1500 to 1800 nautical miles, a cruise speed of 330 to 450 knots true airspeed, a service ceiling of FL450, and a gross weight of 16,300 pounds. The Citation 560 model line evolved in a sequence transitioned to the Citation 560 Ultra V in 1994. This series is now represented by the Ultra Encore. Along with the new name, the Ultra Encore features new engines (the PW 535A) with more range and efficiency.
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