Cessna Citation X
Encyclopedia
The Cessna Citation X is a long-range medium business jet
aircraft
. The Citation X is powered by two Rolls-Royce turbofan engines and is built by the Cessna
Aircraft Company in Wichita, Kansas
. It is the fastest production civilian jet in the world. The Citation
brand of business jets encompasses six distinct "families" of aircraft. Although based on the earlier Citation III, VI and VII models, the Citation X is significantly different, with a totally new wing design, engines, and features a glass cockpit
. The Citation Ten is an upgraded model with improved engines and avionics.
, was eight years old. In 1990, Cessna made a proposition for an improved 650 model to their Customer Advisory Council. The council was interested in some new elements such as increased speed and a pressurized baggage compartment. This pushed Cessna toward the Citation X program, which became the new 750 series.
Moreover, Cessna wanted to improve the image of the Citation family. The Citation models that emerged in the 1970s were originally intended to be practical and with good handling qualities. Consequently, they turned out to be much slower than the competing Learjets. Cessna had difficulties in shedding of the popular image of the Citation as a slow airplane, even though their jets had eventually become as fast as the competition.
The development of the Citation X was first announced at the National Business Aviation Association
Convention in New Orleans in October 1990, with the first prototype making its maiden flight on December 21, 1993. Originally scheduled for August 1995, the certification of the Cessna Citation X was delayed several times. First, failure of the airframe and engine to meet Federal Aviation Administration
requirements caused the planned certification date postponement to late November 1995. The main delay reasons were troubles integrating the avionics and the engine to the aircraft, high-altitude and low-speed engine flame out (high wing attack angles caused insufficient airflow), engines not meeting the bird strike
criteria, and directional stability challenges. Efforts to increase the maximum take-off weight of the Citation X by about 800 pounds again delayed the FAA certification schedule, this time to April 1996. These changes were aimed at permitting a full-fuel payload of 1,400 pounds (seven passengers), but Cessna had difficulty achieving a balance between reducing Citation X cabin noise and minimizing the extra weight of sound-dampening materials. The certification, FAA FAR Part 25, Amendment 74, Certification 3, was finally achieved on June 3, 1996.
The first Citation X was delivered in July 1996 to golfer and long-time Cessna customer Arnold Palmer
. Once in use, the Citation X continued to set speed records. Arnold Palmer set one of them in September 1997: 473 knots (927 km/h) on a 5,000 km closed course. In February 1997, the Citation X design team was awarded the National Aeronautic Association
's Robert J. Collier Trophy. The Citation X was approved by Transport Canada
on May 22, 1998, and by the European Joint Aviation Authorities
in 1999. In October 2000, Cessna announced an upgrade for all Citation Xs to be delivered after January 1, 2002. The main characteristics of this upgraded version are a 5% increase in thrust, a 400 lb (181.4 kg) increase in maximum take-off weight and improved Honeywell avionics.
G5000 flight displays with three 14 inch screens and a heads-up display. The elliptical winglets that were available as an aftermarket option on the Citation X will become standard, and a stretch of 38 cm will improve passenger comfort. Due to a 1.4% improvement in SFC and increased thrust, Cessna is advertising an increase in payload of 97 kg, an increase in cruise speed at FL490 from 460 to 479 knots, and a range increase of 190 nmi (352 km). First flight is expected in December 2011. After the aircraft passes certification testing, it will be the fastest civilian aircraft in the world. It is not known at this time whether or not a separate type rating
will be required to pilot this aircraft.
The aircraft incorporates a number of innovative design features. One attribute that is often first noticed is the large diameter of the engine intakes. This feature, related to the high bypass ratio
turbofan, reduces the noise from the engines and improves fuel efficiency. Another obvious characteristic is the highly swept wing
with a supercritical airfoil
, used in order to increase the critical Mach number
and therefore the top speed. The Citation X has 37 degrees of sweepback at the quarter chord, more than any other business jet and, among civil aircraft, second only to the Boeing 747
's 37.5 degrees. The horizontal and vertical stabilizers are also highly swept and are arranged in a T-tail configuration.
fuselage for efficient transonic
flight, and the aforementioned highly swept supercritical wing. The Citation X's wing is slung below the fuselage rather than passing through it. This allows increased volume in the fuselage, a one-piece wing, and simplified wing-fuselage connections.
blades and a three-stage low-pressure turbine. The engine's fan has approximately a 5 to 1 bypass ratio for improved fuel efficiency and low acoustic signature.
aircraft, but has much less space inside the wings.
provides the avionics system for the glass cockpit
. The Honeywell Primus 2000 EFIS flight director system is composed of five 7"x8" CRT screens. Dual flight management systems with GPS are standard.
expected in 2009. The winglets increase range by 150 nm, lower fuel burn by 4-5%, improve hot and high performance as well as climb rate, permitting a climb to FL430 in 22 minutes, as opposed to 26 minutes without the modification. Climb to FL450 at maximum takeoff weight is possible without a step climb
. Cruise speed at altitude is expected to increase by 15 knots, and maximum takeoff weight will increase by 1200 lbs (545 kg). Excluding installation, the kit's projected cost is $395,000.
Business jet
Business jet, private jet or, colloquially, bizjet is a term describing a jet aircraft, usually of smaller size, designed for transporting groups of up to 19 business people or wealthy individuals...
aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
. The Citation X is powered by two Rolls-Royce turbofan engines and is built by the Cessna
Cessna
The Cessna Aircraft Company is an airplane manufacturing corporation headquartered in Wichita, Kansas, USA. Their main products are general aviation aircraft. Although they are the most well known for their small, piston-powered aircraft, they also produce business jets. The company is a subsidiary...
Aircraft Company in Wichita, Kansas
Wichita, Kansas
Wichita is the largest city in the U.S. state of Kansas.As of the 2010 census, the city population was 382,368. Located in south-central Kansas on the Arkansas River, Wichita is the county seat of Sedgwick County and the principal city of the Wichita metropolitan area...
. It is the fastest production civilian jet in the world. The Citation
Cessna Citation
The Cessna Citation is a marketing name used by Cessna for its line of business jets. Rather than one particular model of aircraft, the name applies to several "families" of turbofan-powered aircraft that have been produced over the years...
brand of business jets encompasses six distinct "families" of aircraft. Although based on the earlier Citation III, VI and VII models, the Citation X is significantly different, with a totally new wing design, engines, and features a glass cockpit
Glass cockpit
A glass cockpit is an aircraft cockpit that features electronic instrument displays, typically large LCD screens, as opposed to the traditional style of analog dials and gauges...
. The Citation Ten is an upgraded model with improved engines and avionics.
Development
When the Citation X was announced, the Citation 650 series, the "family" at the top of the product line, which includes the Citations III, VI, and VIICessna Citation III
|-See also:-External links:*...
, was eight years old. In 1990, Cessna made a proposition for an improved 650 model to their Customer Advisory Council. The council was interested in some new elements such as increased speed and a pressurized baggage compartment. This pushed Cessna toward the Citation X program, which became the new 750 series.
Moreover, Cessna wanted to improve the image of the Citation family. The Citation models that emerged in the 1970s were originally intended to be practical and with good handling qualities. Consequently, they turned out to be much slower than the competing Learjets. Cessna had difficulties in shedding of the popular image of the Citation as a slow airplane, even though their jets had eventually become as fast as the competition.
The development of the Citation X was first announced at the National Business Aviation Association
National Business Aviation Association
National Business Aviation Association or NBAA, is a non-profit and nonpartisan 5016 corporation based in Washington, DC, United States. The Association represents more than 8,000 companies....
Convention in New Orleans in October 1990, with the first prototype making its maiden flight on December 21, 1993. Originally scheduled for August 1995, the certification of the Cessna Citation X was delayed several times. First, failure of the airframe and engine to meet Federal Aviation Administration
Federal Aviation Administration
The Federal Aviation Administration is the national aviation authority of the United States. An agency of the United States Department of Transportation, it has authority to regulate and oversee all aspects of civil aviation in the U.S...
requirements caused the planned certification date postponement to late November 1995. The main delay reasons were troubles integrating the avionics and the engine to the aircraft, high-altitude and low-speed engine flame out (high wing attack angles caused insufficient airflow), engines not meeting the bird strike
Bird strike
A bird strike—sometimes called birdstrike, avian ingestion , bird hit, or BASH —is a collision between an airborne animal and a man-made vehicle, especially aircraft...
criteria, and directional stability challenges. Efforts to increase the maximum take-off weight of the Citation X by about 800 pounds again delayed the FAA certification schedule, this time to April 1996. These changes were aimed at permitting a full-fuel payload of 1,400 pounds (seven passengers), but Cessna had difficulty achieving a balance between reducing Citation X cabin noise and minimizing the extra weight of sound-dampening materials. The certification, FAA FAR Part 25, Amendment 74, Certification 3, was finally achieved on June 3, 1996.
The first Citation X was delivered in July 1996 to golfer and long-time Cessna customer Arnold Palmer
Arnold Palmer
Arnold Daniel Palmer is an American professional golfer, who is generally regarded as one of the greatest players in the history of men's professional golf. He has won numerous events on both the PGA Tour and Champions Tour, dating back to 1955...
. Once in use, the Citation X continued to set speed records. Arnold Palmer set one of them in September 1997: 473 knots (927 km/h) on a 5,000 km closed course. In February 1997, the Citation X design team was awarded the National Aeronautic Association
National Aeronautic Association
The National Aeronautic Association of the United States is a non-profit 501 organization and a member of the Fédération Aéronautique Internationale , the international standard setting and record-keeping body for aeronautics and astronautics. NAA is the official record-keeper for United States...
's Robert J. Collier Trophy. The Citation X was approved by Transport Canada
Transport Canada
Transport Canada is the department within the government of Canada which is responsible for developing regulations, policies and services of transportation in Canada. It is part of the Transportation, Infrastructure and Communities portfolio...
on May 22, 1998, and by the European Joint Aviation Authorities
Joint Aviation Authorities
The Joint Aviation Authorities, or JAA, was an associated body of the ECAC representing the civil aviation regulatory authorities of a number of European States who had agreed to co-operate in developing and implementing common safety regulatory standards and procedures...
in 1999. In October 2000, Cessna announced an upgrade for all Citation Xs to be delivered after January 1, 2002. The main characteristics of this upgraded version are a 5% increase in thrust, a 400 lb (181.4 kg) increase in maximum take-off weight and improved Honeywell avionics.
Citation Ten
In 2010, Cessna initiated a major update of the aircraft, the Citation Ten, which includes upgraded AE3007C2 engines with new fans, GarminGarmin
Garmin Ltd. , incorporated in Schaffhausen, Switzerland, is the parent company of a group of companies founded in 1989 by Gary Burrell and Min Kao , that develops consumer, aviation, and marine technologies for the Global Positioning System...
G5000 flight displays with three 14 inch screens and a heads-up display. The elliptical winglets that were available as an aftermarket option on the Citation X will become standard, and a stretch of 38 cm will improve passenger comfort. Due to a 1.4% improvement in SFC and increased thrust, Cessna is advertising an increase in payload of 97 kg, an increase in cruise speed at FL490 from 460 to 479 knots, and a range increase of 190 nmi (352 km). First flight is expected in December 2011. After the aircraft passes certification testing, it will be the fastest civilian aircraft in the world. It is not known at this time whether or not a separate type rating
Type rating
A type rating is an allowance to fly a certain aircraft type that requires additional training beyond the scope of initial license and aircraft class training. What aircraft require a type rating is decided by the local aviation authority...
will be required to pilot this aircraft.
Design
Despite Cessna's long history of building business jets and the number of aircraft in the Citation family, the Citation X was in many ways a completely new aircraft. The wing, tail, tail cone, gear, and systems are designed from scratch and not based on pre-existing aircraft. The Citation X is also the first aircraft from Cessna to use a Rolls-Royce engine and fully integrated avionics. Although the Citation X may look similar to its predecessors, it is almost entirely composed of new parts. Part commonality is limited to some cockpit controls, the windshield, and the tail light bulb. The pressure bulkhead is also similar to previous designs. The Citation X has the same fuselage diameter as the Citations VI and VII; however, the wing attachment to the fuselage is different from the attachment in any previous Citation.The aircraft incorporates a number of innovative design features. One attribute that is often first noticed is the large diameter of the engine intakes. This feature, related to the high bypass ratio
Bypass ratio
The term bypass ratio relates to the design of turbofan engines, commonly used in aviation. It is defined as the ratio between the mass flow rate of air drawn in by the fan bypassing the engine core to the mass flow rate passing through the engine core....
turbofan, reduces the noise from the engines and improves fuel efficiency. Another obvious characteristic is the highly swept wing
Swept wing
A swept wing is a wing planform favored for high subsonic jet speeds first investigated by Germany during the Second World War. Since the introduction of the MiG-15 and North American F-86 which demonstrated a decisive superiority over the slower first generation of straight-wing jet fighters...
with a supercritical airfoil
Supercritical airfoil
A supercritical airfoil is an airfoil designed, primarily, to delay the onset of wave drag in the transonic speed range. Supercritical airfoils are characterized by their flattened upper surface, highly cambered aft section, and greater leading edge radius compared with traditional airfoil shapes...
, used in order to increase the critical Mach number
Critical Mach number
In aerodynamics, the critical Mach number of an aircraft is the lowest Mach number at which the airflow over any part of the aircraft reaches the speed of sound....
and therefore the top speed. The Citation X has 37 degrees of sweepback at the quarter chord, more than any other business jet and, among civil aircraft, second only to the Boeing 747
Boeing 747
The Boeing 747 is a wide-body commercial airliner and cargo transport, often referred to by its original nickname, Jumbo Jet, or Queen of the Skies. It is among the world's most recognizable aircraft, and was the first wide-body ever produced...
's 37.5 degrees. The horizontal and vertical stabilizers are also highly swept and are arranged in a T-tail configuration.
Airframe
A significant amount of effort throughout the design process was directed towards reducing the Citation X's total drag. The resulting design includes an area-ruledArea rule
The Whitcomb area rule, also called the transonic area rule, is a design technique used to reduce an aircraft's drag at transonic and supersonic speeds, particularly between Mach 0.75 and 1.2....
fuselage for efficient transonic
Transonic
Transonic speed is an aeronautics term referring to the condition of flight in which a range of velocities of airflow exist surrounding and flowing past an air vehicle or an airfoil that are concurrently below, at, and above the speed of sound in the range of Mach 0.8 to 1.2, i.e. 600–900 mph...
flight, and the aforementioned highly swept supercritical wing. The Citation X's wing is slung below the fuselage rather than passing through it. This allows increased volume in the fuselage, a one-piece wing, and simplified wing-fuselage connections.
Engines
Depending on the aircraft serial number, the Citation X is powered by either two Rolls-Royce AE 3007C (up to S/N 750-172) or AE 3007C1 engines (S/N 750-173 and subsequent), each with 6442 lbs (28.66 kN) or 6764 lbs (30.09 kN) of thrust, respectively. They are pod-mounted on the sides of the rear fuselage. It is the first Cessna aircraft to be powered by a Rolls-Royce engine. The engine has solid titaniumTitanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....
blades and a three-stage low-pressure turbine. The engine's fan has approximately a 5 to 1 bypass ratio for improved fuel efficiency and low acoustic signature.
Powered controls
Another first for Cessna is the inclusion of powered controls in the Citation X. The controls are powered by dual-hydraulic systems for redundancy. There are two elevators and the tailplane is all-moving for trim. The rudder is in two pieces: the lower portion is hydraulically-powered and the upper portion is electrically powered. Each wing has five spoiler panels, to be used both for roll control (in addition to the ailerons) and as speed brakes. One of the major challenges of the Citation X design was finding enough space in the wing to run all the necessary hydraulic lines. As Paul Kalberer, the chief engineer of the Citation X program, explained, the Citation X needs just as many hydraulic pumps and actuators as a BoeingBoeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
aircraft, but has much less space inside the wings.
Avionics
HoneywellHoneywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....
provides the avionics system for the glass cockpit
Glass cockpit
A glass cockpit is an aircraft cockpit that features electronic instrument displays, typically large LCD screens, as opposed to the traditional style of analog dials and gauges...
. The Honeywell Primus 2000 EFIS flight director system is composed of five 7"x8" CRT screens. Dual flight management systems with GPS are standard.
Elliptical Winglets
In 2008, Winglet Technology, with the help of Cessna, began flight testing epoxy/graphite elliptical winglets on a Citation X. Flight testing was nearing completion in late 2008, with FAA supplemental type certificationSupplemental Type Certificate
A Supplemental Type Certificate is an FAA approved major modification or repair to an existing type certified aircraft, engine or propeller. As it adds to the existing type certificate, it is deemed 'supplemental'.-Purpose:...
expected in 2009. The winglets increase range by 150 nm, lower fuel burn by 4-5%, improve hot and high performance as well as climb rate, permitting a climb to FL430 in 22 minutes, as opposed to 26 minutes without the modification. Climb to FL450 at maximum takeoff weight is possible without a step climb
Step climb
A step climb in aviation is a series of altitude gains that improve fuel economy by moving into thinner air as an aircraft becomes lighter and becomes capable of faster, more economical flight.-Description:...
. Cruise speed at altitude is expected to increase by 15 knots, and maximum takeoff weight will increase by 1200 lbs (545 kg). Excluding installation, the kit's projected cost is $395,000.