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Aircraft design process

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The aircraft design process is a loosely defined method used to balance many competing and demanding requirements to produce an aircraft that is strong, lightweight, economical and can carry an adequate payload while being sufficiently reliable to safely fly for the design life of the aircraft. Similar to, but more exacting than, the usual <a href="Engineering_design_process" title="Engineering design process">engineering design process</a>, the technique is highly iterative, involving high-level configuration tradeoffs, a mixture of analysis and testing and the detailed examination of the adequacy of every part of the structure. For some types of aircraft, the design process is regulated by <a href="Civil_aviation_authority" title="Civil aviation authority">civil airworthiness authorities</a>.

This article deals with powered <a href="Aircraft" title="Aircraft">aircraft</a> such as <a href="Airplane" title="Airplane">airplanes</a> and <a href="Helicopter" title="Helicopter">helicopter</a> designs.

<div class="mw-heading mw-heading2"><h2 id="Design_constraints">Design constraints</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Purpose">Purpose</h3></div>

The design process starts with the aircraft's intended purpose. Commercial airliners are designed for carrying a passenger or cargo payload, long range and greater fuel efficiency whereas fighter jets are designed to perform high speed maneuvers and provide close support to ground troops. Some aircraft have specific missions, for instance, <a href="Amphibious_aircraft" title="Amphibious aircraft">amphibious airplanes</a> have a unique design that allows them to operate from both land and water, some fighters, like the <a href="Harrier_jump_jet" title="Harrier jump jet">Harrier jump jet</a>, have <a href="VTOL" title="VTOL">VTOL</a> (vertical take-off and landing) ability, helicopters have the ability to hover over an area for a period of time.<a href="#cite_note-1">[1]</a>

The purpose may be to fit a specific requirement, e.g. as in the historical case of a <a href="List_of_Air_Ministry_specifications" title="List of Air Ministry specifications">British Air Ministry specification</a>, or fill a perceived "gap in the market"; that is, a class or design of aircraft which does not yet exist, but for which there would be significant demand.

<div class="mw-heading mw-heading3"><h3 id="Aircraft_regulations">Aircraft regulations</h3></div>

Another important factor that influences the design are the requirements for obtaining a <a href="Type_certificate" title="Type certificate">type certificate</a> for a new design of aircraft. These requirements are published by major national airworthiness authorities including the US <a href="Federal_Aviation_Administration" title="Federal Aviation Administration">Federal Aviation Administration</a> and the <a href="European_Aviation_Safety_Agency" class="mw-redirect" title="European Aviation Safety Agency">European Aviation Safety Agency</a>.<a href="#cite_note-2">[2]</a><a href="#cite_note-3">[3]</a>

Airports may also impose limits on aircraft, for instance, the maximum wingspan allowed for a conventional aircraft is 80 metres (260 ft) to prevent collisions between aircraft while taxiing.<a href="#cite_note-4">[4]</a>

<div class="mw-heading mw-heading3"><h3 id="Financial_factors_and_market">Financial factors and market</h3></div>

Budget limitations, market requirements and competition set constraints on the design process and comprise the non-technical influences on aircraft design along with environmental factors. Competition leads to companies striving for better efficiency in the design without compromising performance and incorporating new techniques and technology.<a href="#cite_note-5">[5]</a>

In the 1950s and '60s, unattainable project goals were regularly set, but then abandoned, whereas today troubled programs like the <a href="Boeing_787" class="mw-redirect" title="Boeing 787">Boeing 787</a> and the <a href="Lockheed_Martin_F-35" class="mw-redirect" title="Lockheed Martin F-35">Lockheed Martin F-35</a> have proven far more costly and complex to develop than expected.

More advanced and integrated design tools have been developed. <a href="Model-based_systems_engineering" title="Model-based systems engineering">Model-based systems engineering</a> predicts potentially problematic interactions, while <a href="Computational_science" title="Computational science">computational analysis</a> and optimization allows designers to explore more options early in the process. Increasing <a href="Automation" title="Automation">automation</a> in engineering and manufacturing allows faster and cheaper development.

Technology advances from materials to manufacturing enable more complex design variations like multifunction parts. Once impossible to design or construct, these can now be <a href="3D_printed" class="mw-redirect" title="3D printed">3D printed</a>, but they have yet to prove their utility in applications like the <a href="Northrop_Grumman_B-21" class="mw-redirect" title="Northrop Grumman B-21">Northrop Grumman B-21</a> or the re-engined <a href="A320neo" class="mw-redirect" title="A320neo">A320neo</a> and <a href="737_MAX" class="mw-redirect" title="737 MAX">737 MAX</a>. <a href="Airbus_and_Boeing" class="mw-redirect" title="Airbus and Boeing">Airbus and Boeing</a> also recognize the economic limits, that the next <a href="Airliner" title="Airliner">airliner</a> generation cannot cost more than the previous ones did.<a href="#cite_note-AvWeek6may2016-6">[6]</a>

<div class="mw-heading mw-heading3"><h3 id="Environmental_factors">Environmental factors</h3></div>

An increase in the number of aircraft also means greater carbon emissions. Environmental scientists have voiced concern over the main kinds of pollution associated with aircraft, mainly noise and emissions. Aircraft engines have been historically notorious for creating noise pollution and the expansion of airways over already congested and polluted cities have drawn heavy criticism, making it necessary to have environmental policies for aircraft noise.<a href="#cite_note-7">[7]</a><a href="#cite_note-8">[8]</a> Noise also arises from the airframe, where the airflow directions are changed.<a href="#cite_note-9">[9]</a> Improved noise regulations have forced designers to create quieter engines and airframes.<a href="#cite_note-10">[10]</a> Emissions from aircraft include particulates, <a href="Carbon_dioxide" title="Carbon dioxide">carbon dioxide</a> (CO2), <a href="Sulfur_dioxide" title="Sulfur dioxide">sulfur dioxide</a> (SO2), <a href="Carbon_monoxide" title="Carbon monoxide">carbon monoxide</a> (CO), various <a href="Oxides" class="mw-redirect" title="Oxides">oxides</a> of <a href="Nitrates" class="mw-redirect" title="Nitrates">nitrates</a> and unburnt <a href="Hydrocarbons" class="mw-redirect" title="Hydrocarbons">hydrocarbons</a>.<a href="#cite_note-11">[11]</a> To combat the pollution, ICAO set recommendations in 1981 to control aircraft emissions.<a href="#cite_note-Doc_9889-12">[12]</a> Newer, environmentally friendly fuels have been developed<a href="#cite_note-13">[13]</a> and the use of recyclable materials in manufacturing<a href="#cite_note-14">[14]</a> have helped reduce the ecological impact due to aircraft. Environmental limitations also affect airfield compatibility. Airports around the world have been built to suit the topography of the particular region. Space limitations, pavement design, <a href="Runway" title="Runway">runway</a> end safety areas and the unique location of airport are some of the airport factors that influence aircraft design. However changes in aircraft design also influence airfield design as well, for instance, the recent introduction of new large aircraft (NLAs) such as the superjumbo <a href="Airbus_A380" title="Airbus A380">Airbus A380</a>, have led to airports worldwide redesigning their facilities to accommodate its large size and service requirements.<a href="#cite_note-15">[15]</a><a href="#cite_note-16">[16]</a>

<div class="mw-heading mw-heading3"><h3 id="Safety">Safety</h3></div>

The high speeds, fuel tanks, atmospheric conditions at cruise altitudes, natural hazards (thunderstorms, hail and bird strikes) and human error are some of the many hazards that pose a threat to air travel.<a href="#cite_note-17">[17]</a><a href="#cite_note-18">[18]</a><a href="#cite_note-19">[19]</a>

<a href="Airworthiness" title="Airworthiness">Airworthiness</a> is the standard by which aircraft are determined fit to fly.<a href="#cite_note-20">[20]</a> The responsibility for airworthiness lies with the national civil aviation regulatory bodies, <a href="Aircraft_manufacturers" class="mw-redirect" title="Aircraft manufacturers">manufacturers</a>, as well as owners and operators.

The <a href="International_Civil_Aviation_Organization" title="International Civil Aviation Organization">International Civil Aviation Organization</a> sets international standards and recommended practices on which national authorities should base their regulations.<a href="#cite_note-21">[21]</a><a href="#cite_note-22">[22]</a> The national regulatory authorities set standards for airworthiness, issue certificates to manufacturers and operators and the standards of personnel training.<a href="#cite_note-23">[23]</a> Every country has its own regulatory body such as the <a href="Federal_Aviation_Administration" title="Federal Aviation Administration">Federal Aviation Administration</a> in USA, <a href="Directorate_General_of_Civil_Aviation_(India)" title="Directorate General of Civil Aviation (India)">DGCA (Directorate General of Civil Aviation)</a> in India, etc.

The aircraft manufacturer makes sure that the aircraft meets existing design standards, defines the operating limitations and maintenance schedules and provides support and maintenance throughout the operational life of the aircraft. The aviation operators include the <a href="Civil_aviation" title="Civil aviation">passenger and cargo airliners</a>, <a href="Military_aviation" title="Military aviation">air forces</a> and owners of private aircraft. They agree to comply with the regulations set by the regulatory bodies, understand the limitations of the aircraft as specified by the manufacturer, report defects and assist the manufacturers in keeping up the airworthiness standards.

Most of the design criticisms these days are built on <a href="Crashworthiness" title="Crashworthiness">crashworthiness</a>. Even with the greatest attention to airworthiness, accidents still occur. Crashworthiness is the qualitative evaluation of how aircraft survive an accident. The main objective is to protect the passengers or valuable cargo from the damage caused by an accident. In the case of airliners the stressed skin of the pressurized fuselage provides this feature, but in the event of a nose or tail impact, large bending moments build all the way through the fuselage, causing fractures in the shell, causing the fuselage to break up into smaller sections.<a href="#cite_note-24">[24]</a> So the passenger aircraft are designed in such a way that seating arrangements are away from areas likely to be intruded in an accident, such as near a propeller, engine nacelle undercarriage etc.<a href="#cite_note-25">[25]</a> The interior of the cabin is also fitted with safety features such as oxygen masks that drop down in the event of loss of cabin pressure, lockable luggage compartments, safety belts, lifejackets, emergency doors and luminous floor strips. Aircraft are sometimes designed with emergency <a href="Water_landing" title="Water landing">water landing</a> in mind, for instance the <a href="Airbus_A330" title="Airbus A330">Airbus A330</a> has a 'ditching' switch that closes valves and openings beneath the aircraft slowing the ingress of water.<a href="#cite_note-26">[26]</a>

<div class="mw-heading mw-heading2"><h2 id="Design_optimization">Design optimization</h2></div>

Aircraft designers normally rough-out the initial design with consideration of all the constraints on their design. Historically design teams used to be small, usually headed by a Chief Designer who knows all the design requirements and objectives and coordinated the team accordingly. As time progressed, the complexity of military and airline aircraft also grew. Modern military and airline design projects are of such a large scale that every design aspect is tackled by different teams and then brought together. In general aviation a large number of light aircraft are designed and built by <a href="Homebuilt_aircraft" title="Homebuilt aircraft">amateur hobbyists and enthusiasts</a>.<a href="#cite_note-27">[27]</a>

<div class="mw-heading mw-heading2"><h2 id="Computer-aided_design_of_aircraft">Computer-aided design of aircraft</h2></div>

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</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="OpenVSP" title="OpenVSP">OpenVSP</a>, <a href="FlightGear#JSBSim" title="FlightGear">JSBSim and YASim</a>, and <a href="CATIA" title="CATIA">CATIA</a></div>

In the early years of aircraft design, designers generally used analytical theory to do the various engineering calculations that go into the design process along with a lot of experimentation. These calculations were labour-intensive and time-consuming. In the 1940s, several engineers started looking for ways to automate and simplify the calculation process and many relations and semi-empirical formulas were developed. Even after simplification, the calculations continued to be extensive. With the invention of the computer, engineers realized that a majority of the calculations could be automated, but the lack of design visualization and the huge amount of experimentation involved kept the field of aircraft design stagnant. With the rise of programming languages, engineers could now write programs that were tailored to design an aircraft. Originally this was done with mainframe computers and used low-level programming languages that required the user to be fluent in the language and know the architecture of the computer. With the introduction of personal computers, design programs began employing a more user-friendly approach.<a href="#cite_note-28">[28]</a>

<div class="mw-heading mw-heading2"><h2 id="Design_aspects">Design aspects</h2></div>

The main aspects of aircraft design are:

<ol><li><a href="Aerodynamics" title="Aerodynamics">Aerodynamics</a></li>

<li><a href="Powered_aircraft" class="mw-redirect" title="Powered aircraft">Propulsion</a></li>

<li><a href="Aircraft_flight_control_system" title="Aircraft flight control system">Controls</a></li>

<li><a href="Fixed-wing_aircraft#structure" title="Fixed-wing aircraft">Structure</a></li></ol>

All aircraft designs involve compromises of these factors to achieve the design mission.<a href="#cite_note-29">[29]</a>

<div class="mw-heading mw-heading3"><h3 id="Wing_design">Wing design</h3></div>

<div role="note" class="hatnote navigation-not-searchable">See also: <a href="Wing_configuration" title="Wing configuration">Wing configuration</a></div>

The wing of a fixed-wing aircraft provides the lift necessary for flight. Wing geometry affects every aspect of an aircraft's flight. The wing area will usually be dictated by the desired <a href="Stalling_speed" class="mw-redirect" title="Stalling speed">stalling speed</a> but the overall shape of the <a href="Planform_(aeronautics)" class="mw-redirect" title="Planform (aeronautics)">planform</a> and other detail aspects may be influenced by wing layout factors.<a href="#cite_note-30">[30]</a> The wing can be mounted to the fuselage in high, low and middle positions. The wing design depends on many parameters such as selection of <a href="Aspect_ratio" title="Aspect ratio">aspect ratio</a>, taper ratio, <a href="Sweepback" class="mw-redirect" title="Sweepback">sweepback</a> angle, thickness ratio, section profile, <a href="Washout_(aviation)" class="mw-redirect" title="Washout (aviation)">washout</a> and <a href="Dihedral_(aircraft)" class="mw-redirect" title="Dihedral (aircraft)">dihedral</a>.<a href="#cite_note-31">[31]</a> The cross-sectional shape of the wing is its <a href="Airfoil" title="Airfoil">airfoil</a>.<a href="#cite_note-32">[32]</a> The construction of the wing starts with the <a href="Rib_(aircraft)" class="mw-redirect" title="Rib (aircraft)">rib</a> which defines the airfoil shape. Ribs can be made of wood, metal, plastic or even composites.<a href="#cite_note-33">[33]</a>

The wing must be designed and tested to ensure it can withstand the maximum loads imposed by maneuvering, and by atmospheric gusts.

<div class="mw-heading mw-heading3"><h3 id="Fuselage">Fuselage</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Fuselage" title="Fuselage">Fuselage</a></div>

The fuselage is the part of the aircraft that contains the <a href="Cockpit" title="Cockpit">cockpit</a>, passenger cabin or cargo hold.<a href="#cite_note-34">[34]</a>

<div class="mw-heading mw-heading3"><h3 id="Empennage">Empennage</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Empennage" title="Empennage">Empennage</a></div>

<div class="mw-heading mw-heading3"><h3 id="Propulsion">Propulsion</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Aircraft_engine" title="Aircraft engine">Aircraft engine</a></div>

Aircraft propulsion may be achieved by specially designed aircraft engines, adapted auto, motorcycle or snowmobile engines, electric engines or even human muscle power. The main parameters of engine design are:<a href="#cite_note-35">[35]</a>

<ul><li>Maximum engine thrust available</li>

<li>Fuel consumption</li>

<li>Engine mass</li>

<li>Engine geometry</li></ul>

The thrust provided by the engine must balance the drag at cruise speed and be greater than the drag to allow acceleration. The engine requirement varies with the type of aircraft. For instance, commercial airliners spend more time in cruise speed and need more engine efficiency. High-performance fighter jets need very high acceleration and therefore have very high thrust requirements.<a href="#cite_note-36">[36]</a>

<div class="mw-heading mw-heading3"><h3 id="Landing_gear">Landing gear</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Landing_gear" title="Landing gear">Landing gear</a></div>

<div class="mw-heading mw-heading3"><h3 id="Weight">Weight</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Aircraft_gross_weight" title="Aircraft gross weight">Aircraft gross weight</a></div>

The weight of the aircraft is the common factor that links all aspects of aircraft design such as aerodynamics, structure, and propulsion, all together. An aircraft's weight is derived from various factors such as empty weight, payload, useful load, etc. The various weights are used to then calculate the center of mass of the entire aircraft.<a href="#cite_note-37">[37]</a> The center of mass must fit within the established limits set by the manufacturer.

<div class="mw-heading mw-heading3"><h3 id="Structure">Structure</h3></div>

The aircraft structure focuses not only on strength, <a href="Aeroelasticity" title="Aeroelasticity">aeroelasticity</a>, <a href="Fatigue_(material)" title="Fatigue (material)">durability</a>, <a href="Damage_tolerance" title="Damage tolerance">damage tolerance</a>, <a href="Flight_dynamics" title="Flight dynamics">stability</a>, but also on <a href="Fail-safe" title="Fail-safe">fail-safety</a>, <a href="Corrosion" title="Corrosion">corrosion</a> resistance, maintainability and ease of manufacturing. The structure must be able to withstand the stresses caused by <a href="Cabin_pressurization" title="Cabin pressurization">cabin pressurization</a>, if fitted, turbulence and engine or rotor vibrations.<a href="#cite_note-38">[38]</a>

<div class="mw-heading mw-heading2"><h2 id="Design_process_and_simulation">Design process and simulation</h2></div>

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The design of any aircraft starts out in three phases<a href="#cite_note-39">[39]</a>

<div class="mw-heading mw-heading3"><h3 id="Conceptual_design">Conceptual design</h3></div>

Aircraft conceptual design involves sketching a variety of possible configurations that meet the required design specifications. By drawing a set of configurations, designers seek to reach the design configuration that satisfactorily meets all requirements as well as go hand in hand with factors such as aerodynamics, propulsion, flight performance, structural and control systems.<a href="#cite_note-40">[40]</a> This is called design optimization. Fundamental aspects such as fuselage shape, wing configuration and location, engine size and type are all determined at this stage. Constraints to design like those mentioned above are all taken into account at this stage as well. The final product is a conceptual layout of the aircraft configuration on paper or computer screen, to be reviewed by engineers and other designers.

<div class="mw-heading mw-heading3"><h3 id="Preliminary_design_phase">Preliminary design phase</h3></div>

The design configuration arrived at in the conceptual design phase is then tweaked and remodeled to fit into the design parameters. In this phase, <a href="Wind_tunnel" title="Wind tunnel">wind tunnel</a> testing and <a href="Computational_fluid_dynamics" title="Computational fluid dynamics">computational fluid dynamic</a> calculations of the flow field around the aircraft are done. Major structural and control analysis is also carried out in this phase. Aerodynamic flaws and structural instabilities if any are corrected and the final design is drawn and finalized. Then after the finalization of the design lies the key decision with the manufacturer or individual designing it whether to actually go ahead with the production of the aircraft.<a href="#cite_note-41">[41]</a> At this point several designs, though perfectly capable of flight and performance, might have been opted out of production due to their being economically nonviable.

<div class="mw-heading mw-heading3"><h3 id="Detail_design_phase">Detail design phase</h3></div>

This phase simply deals with the fabrication aspect of the aircraft to be manufactured. It determines the number, design and location of <a href="Rib_(aircraft)" class="mw-redirect" title="Rib (aircraft)">ribs</a>, <a href="Spar_(aviation)" class="mw-redirect" title="Spar (aviation)">spars</a>, sections and other structural elements.<a href="#cite_note-42">[42]</a> All aerodynamic, structural, propulsion, control and performance aspects have already been covered in the preliminary design phase and only the manufacturing remains. <a href="Flight_simulator" title="Flight simulator">Flight simulators</a> for aircraft are also developed at this stage.

<div class="mw-heading mw-heading3"><h3 id="Delays">Delays</h3></div>

Some commercial aircraft have experienced significant schedule delays and cost overruns in the development phase. Examples of this include the <a href="Boeing_787_Dreamliner" title="Boeing 787 Dreamliner">Boeing 787 Dreamliner</a> with a delay of 4 years with massive cost overruns, the <a href="Boeing_747-8" title="Boeing 747-8">Boeing 747-8</a> with a two-year delay, the <a href="Airbus_A380" title="Airbus A380">Airbus A380</a> with a two-year delay and US$6.1 billion in cost overruns, the <a href="Airbus_A350" title="Airbus A350">Airbus A350</a> with delays and cost overruns, the <a href="Bombardier_C_Series" class="mw-redirect" title="Bombardier C Series">Bombardier C Series</a>, <a href="Global_7000" class="mw-redirect" title="Global 7000">Global 7000</a> and 8000, the <a href="Comac_C919" title="Comac C919">Comac C919</a> with a four-year delay and the <a href="Mitsubishi_Regional_Jet" class="mw-redirect" title="Mitsubishi Regional Jet">Mitsubishi Regional Jet</a>, which was delayed by four years and ended up with empty weight issues.<a href="#cite_note-43">[43]</a>

<div class="mw-heading mw-heading2"><h2 id="Program_development">Program development</h2></div>

An existing aircraft program can be developed for performance and economy gains by stretching the <a href="Fuselage" title="Fuselage">fuselage</a>, increasing the <a href="MTOW" class="mw-redirect" title="MTOW">MTOW</a>, enhancing the aerodynamics, installing new <a href="Aircraft_engine" title="Aircraft engine">engines</a>, new wings or new avionics.

For a 9,100 nmi long range at Mach 0.8/FL360, a 10% lower <a href="Thrust_specific_fuel_consumption" class="mw-redirect" title="Thrust specific fuel consumption">TSFC</a> saves 13% of fuel, a 10% <a href="Lift-to-drag_ratio" title="Lift-to-drag ratio">L/D</a> increase saves 12%, a 10% lower <a href="OEW" class="mw-redirect" title="OEW">OEW</a> saves 6% and all combined saves 28%.<a href="#cite_note-44">[44]</a>

<div class="mw-heading mw-heading3"><h3 id="Re-engine">Re-engine</h3></div>

<caption>Jet airliners

</caption>

<th>Previous engines</th>

<th>First flight</th>

<th>Re-engined</th>

<th>New engines</th>

<th data-sort-type="date">First flight

</th></tr>

<tr>

<td><a href="Douglas_DC-8#Super_60_Series" title="Douglas DC-8">DC-8 Super 60</a></td>

<td>May 30, 1958

</td>

<td><a href="Douglas_DC-8#Super_70_Series" title="Douglas DC-8">DC-8 Super 70</a></td>

<td>1982

</td></tr>

<tr>

<td><a href="Boeing_737_Original" class="mw-redirect" title="Boeing 737 Original">Boeing 737 Original</a></td>

<td>Apr 9, 1967

</td>

<td><a href="Boeing_737_Classic" title="Boeing 737 Classic">Boeing 737 Classic</a></td>

<td>Feb 24, 1984

</td></tr>

<tr>

<td><a href="Fokker_F28" class="mw-redirect" title="Fokker F28">Fokker F28</a></td>

<td><a href="Rolls-Royce_Spey" title="Rolls-Royce Spey">Rolls-Royce Spey</a></td>

<td>May 9, 1967

</td>

<td><a href="Fokker_100" title="Fokker 100">Fokker 100</a>/70</td>

<td><a href="Rolls-Royce_RB.183_Tay" title="Rolls-Royce RB.183 Tay">Rolls-Royce Tay</a></td>

<td>Nov 30, 1986

</td></tr>

<tr>

<td><a href="Boeing_747" title="Boeing 747">Boeing 747</a></td>

<td>Feb 9, 1969

</td>

<td><a href="Boeing_747-400" title="Boeing 747-400">Boeing 747-400</a></td>

<td>Apr 29, 1988

</td></tr>

<tr>

<td><a href="Douglas_DC-10" class="mw-redirect" title="Douglas DC-10">Douglas DC-10</a></td>

<td>Aug 29, 1970

</td>

<td>Jan 10, 1990

</td></tr>

<tr>

<td><a href="Douglas_DC-9" class="mw-redirect" title="Douglas DC-9">Douglas DC-9</a>/<a href="MD-80" class="mw-redirect" title="MD-80">MD-80</a></td>

<td>Feb 25, 1965

</td>

<td>Feb 22, 1993

</td></tr>

<tr>

<td>Boeing 737 Classic</td>

<td>Feb 24, 1984

</td>

<td><a href="Boeing_737_NG" class="mw-redirect" title="Boeing 737 NG">Boeing 737 NG</a></td>

<td>Feb 9, 1997

</td></tr>

<tr>

<td>Boeing 747-400</td>

<td>Apr 29, 1988

</td>

<td><a href="Boeing_747-8" title="Boeing 747-8">Boeing 747-8</a></td>

<td>Feb 8, 2010

</td></tr>

<tr>

<td><a href="Airbus_A320" class="mw-redirect" title="Airbus A320">Airbus A320</a></td>

<td>Feb 22, 1987

</td>

<td><a href="Airbus_A320neo" class="mw-redirect" title="Airbus A320neo">Airbus A320neo</a></td>

<td>Sep 25, 2014

</td></tr>

<tr>

<td>Boeing 737 NG</td>

<td>Feb 9, 1997

</td>

<td><a href="Boeing_737_MAX" title="Boeing 737 MAX">Boeing 737 MAX</a></td>

<td>Jan 29, 2016

</td></tr>

<tr>

<td><a href="Embraer_E-Jet" class="mw-redirect" title="Embraer E-Jet">Embraer E-Jet</a></td>

<td>Feb 19, 2002

</td>

<td><a href="Embraer_E-Jet_E2" class="mw-redirect" title="Embraer E-Jet E2">Embraer E-Jet E2</a></td>

<td>May 23, 2016

</td></tr>

<tr>

<td><a href="Airbus_A330" title="Airbus A330">Airbus A330</a></td>

<td>CF6/PW4000/<a href="Trent_700" class="mw-redirect" title="Trent 700">Trent 700</a></td>

<td>Nov 2, 1992

</td>

<td><a href="Airbus_A330neo" title="Airbus A330neo">Airbus A330neo</a></td>

<td><a href="Trent_7000" class="mw-redirect" title="Trent 7000">Trent 7000</a></td>

<td>Oct 19, 2017

</td></tr>

<tr>

<td><a href="Boeing_777" title="Boeing 777">Boeing 777</a></td>

<td><a href="GE90" class="mw-redirect" title="GE90">GE90</a>/PW4000/<a href="Trent_800" class="mw-redirect" title="Trent 800">Trent 800</a></td>

<td>Jun 12, 1994

</td>

<td><a href="Boeing_777X" title="Boeing 777X">Boeing 777X</a></td>

<td>Jan 25, 2020

</td></tr></tbody></table>

<div class="mw-heading mw-heading3"><h3 id="Fuselage_stretch">Fuselage stretch</h3></div>

<caption>Jet airliners

</caption>

<th>Base length</th>

<th>First flight</th>

<th>Stretched</th>

<th>Stretched length</th>

<th data-sort-type="date">First flight

</th></tr>

<tr>

<td rowspan="8"><a href="Boeing_737-100" class="mw-redirect" title="Boeing 737-100">Boeing 737-100</a></td>

<td rowspan="8">Apr 9, 1967

</td>

<td>Aug 8, 1967

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>

</td></tr>

<tr>

<td>plan. 2020

</td></tr>

<tr>

<td rowspan="2"><a href="Boeing_747" title="Boeing 747">Boeing 747</a>-100/200/300/400</td>

<td rowspan="2">Feb 9, 1969

</td>

<td><a href="Boeing_747SP" title="Boeing 747SP">Boeing 747SP</a></td>

<td>Jul 4, 1975

</td></tr>

<tr>

<td><a href="Boeing_747-8" title="Boeing 747-8">Boeing 747-8</a></td>

<td>Feb 8, 2010

</td></tr>

<tr>

<td><a href="Boeing_757" title="Boeing 757">Boeing 757</a></td>

<td>Feb 19, 1982

</td>

<td>Boeing 757-300</td>

<td>

</td></tr>

<tr>

<td rowspan="2"><a href="Boeing_767" title="Boeing 767">Boeing 767</a>-200/ER</td>

<td rowspan="2">Sep 26, 1981

</td>

<td>Boeing 767-300/ER</td>

<td>

</td></tr>

<tr>

<td>Boeing 767-400ER</td>

<td>

</td></tr>

<tr>

<td rowspan="3"><a href="Boeing_777" title="Boeing 777">Boeing 777</a>-200/ER/LR</td>

<td rowspan="3">Jun 12, 1994

</td>

<td><a href="Boeing_777X" title="Boeing 777X">Boeing 777X</a>-8</td>

<td>

</td></tr>

<tr>

<td>Boeing 777-300/ER</td>

<td>Oct 16, 1997

</td></tr>

<tr>

<td>Boeing 777X-9</td>

<td>Jan 25, 2020

</td></tr>

<tr>

<td rowspan="2"><a href="Boeing_787" class="mw-redirect" title="Boeing 787">Boeing 787</a>-8</td>

<td rowspan="2">Dec 15, 2009

</td>

<td>Boeing 787-9</td>

<td>Sep 17, 2013

</td></tr>

<tr>

<td>Boeing 787-10</td>

<td>Mar 31, 2017

</td></tr>

<tr>

<td><a href="Airbus_A300" title="Airbus A300">Airbus A300</a></td>

<td>Oct 28, 1972

</td>

<td><a href="Airbus_A310" title="Airbus A310">Airbus A310</a></td>

<td>Apr 3, 1982

</td></tr>

<tr>

<td rowspan="3"><a href="Airbus_A320" class="mw-redirect" title="Airbus A320">Airbus A320</a> (neo)</td>

<td rowspan="3">Feb 22, 1987

</td>

<td><a href="Airbus_A318" title="Airbus A318">Airbus A318</a></td>

<td>Jan 15, 2002

</td></tr>

<tr>

<td><a href="Airbus_A319" title="Airbus A319">Airbus A319</a> (neo)</td>

<td>Aug 25, 1995

</td></tr>

<tr>

<td><a href="Airbus_A321" title="Airbus A321">Airbus A321</a> (neo)</td>

<td>Mar 11, 1993

</td></tr>

<tr>

<td><a href="Airbus_A330-300" class="mw-redirect" title="Airbus A330-300">Airbus A330-300</a>/900</td>

<td>Nov 2, 1992

</td>

<td><a href="Airbus_A330-200" class="mw-redirect" title="Airbus A330-200">Airbus A330-200</a>/800</td>

<td>Aug 13, 1997

</td></tr>

<tr>

<td rowspan="3"><a href="Airbus_A340-300" class="mw-redirect" title="Airbus A340-300">Airbus A340-300</a></td>

<td rowspan="3">Oct 25, 1991

</td>

<td><a href="Airbus_A340-200" class="mw-redirect" title="Airbus A340-200">Airbus A340-200</a></td>

<td>Apr 1, 1992

</td></tr>

<tr>

<td><a href="Airbus_A340-500" class="mw-redirect" title="Airbus A340-500">Airbus A340-500</a></td>

<td>Feb 11, 2002

</td></tr>

<tr>

<td><a href="Airbus_A340-600" class="mw-redirect" title="Airbus A340-600">Airbus A340-600</a></td>

<td>Apr 23, 2001

</td></tr>

<tr>

<td><a href="Airbus_A350" title="Airbus A350">Airbus A350</a>-900</td>

<td>Jun 14, 2013

</td>

<td>Nov 24, 2016

</td></tr></tbody></table>

<ul><li><a href="Index_of_aviation_articles" title="Index of aviation articles">Index of aviation articles</a></li>

<li><a href="Aerospace_engineering" title="Aerospace engineering">Aerospace engineering</a></li>

<li><a href="Aircraft_manufacturer" class="mw-redirect" title="Aircraft manufacturer">Aircraft manufacturer</a></li>

<li><a href="Iron_bird_(aviation)" title="Iron bird (aviation)">Iron bird (aviation)</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.dynamicflight.com/flight_maneuvers/hovering/">"Hovering"</a>. Flight maneuvers. www.dynamicflight.com. Retrieved 2011-10-10.</cite>

</li>

<li id="cite_note-2"><a href="#cite_ref-2">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110417023605/http://www.tc.gc.ca/eng/civilaviation/publications/tp14371-lra-2-0-2566.htm#2-7">"Airworthiness - Transport Canada"</a>. Airworthiness Directives. Transport Canada. Archived from <a rel="nofollow" class="external text" href="http://www.tc.gc.ca/eng/civilaviation/publications/tp14371-lra-2-0-2566.htm#2-7">the original</a> on 2011-04-17. Retrieved 2011-12-05.</cite>

</li>

<li id="cite_note-3"><a href="#cite_ref-3">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20111213182816/http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_90822">"Airworthiness - CASA"</a>. Airworthiness Directives. CASA - Australian Government. Archived from <a rel="nofollow" class="external text" href="http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_90822">the original</a> on 2011-12-13. Retrieved 2011-12-05.</cite>

</li>

<li id="cite_note-4"><a href="#cite_ref-4">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.icao.int/fsix/_Library%5CManual%20Aerodrome%20Stds.pdf">"ICAO Aerodrome Standards"</a> (PDF). ICAO Regulations. ICAO. Retrieved 5 October 2011.</cite>

</li>

<li id="cite_note-5"><a href="#cite_ref-5">^</a> <cite id="CITEREFLloyd_R._JenkinsonPaul_SimpkinDarren_Rhodes1999" class="citation book cs1">Lloyd R. Jenkinson; Paul Simpkin; Darren Rhodes (1999). "Aircraft Market". Civil Jet Aircraft Design. Great Britain: Arnold Publishers. p. 10. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-340-74152-X</bdi>.</cite>

</li>

<li id="cite_note-AvWeek6may2016-6"><a href="#cite_ref-AvWeek6may2016_6-0">^</a> <cite id="CITEREFGraham_Warwick2016" class="citation news cs1">Graham Warwick (May 6, 2016). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180102170422/http://aviationweek.com/technology-milestones/problems-aerospace-still-has-solve">"Problems Aerospace Still Has To Solve"</a>. Aviation Week & Space Technology. Archived from <a rel="nofollow" class="external text" href="http://aviationweek.com/technology-milestones/problems-aerospace-still-has-solve">the original</a> on January 2, 2018. Retrieved January 2, 2018.</cite>

</li>

<li id="cite_note-7"><a href="#cite_ref-7">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20090417003255/http://ec.europa.eu/transport/air/environment/aircraft_noise_en.htm">"Travel(Air) - Aircraft Noise"</a>. Mobility and Transport. European Commission. 2010-10-30. Archived from <a rel="nofollow" class="external text" href="http://ec.europa.eu/transport/air/environment/aircraft_noise_en.htm">the original</a> on 2009-04-17. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-8"><a href="#cite_ref-8">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20111005040825/http://www.icao.int/icaonet/anx/info/annexes_booklet_en.pdf">"Annex 16 - Environmental Protection"</a> (PDF). Convention on International Civil Aviation. ICAO. p. 29. Archived from <a rel="nofollow" class="external text" href="http://www.icao.int/icaonet/anx/info/annexes_booklet_en.pdf">the original</a> (PDF) on October 5, 2011. Retrieved 8 October 2011.</cite>

</li>

<li id="cite_note-9"><a href="#cite_ref-9">^</a> <cite id="CITEREFWilliam_Wilshire" class="citation web cs1">William Wilshire. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20111021225904/http://www.aeronautics.nasa.gov/docs/chicago/airframe.htm">"Airframe Noise Reduction"</a>. NASA Aeronautics. NASA. Archived from <a rel="nofollow" class="external text" href="https://www.aeronautics.nasa.gov/docs/chicago/airframe.htm">the original</a> on 2011-10-21. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-10"><a href="#cite_ref-10">^</a> <cite id="CITEREFNeal_Nijhawan" class="citation web cs1">Neal Nijhawan. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20111018200346/http://www.aeronautics.nasa.gov/docs/chicago/noise.htm">"Environment: Aircraft Noise Reduction"</a>. NASA Aeronautics. NASA. Archived from <a rel="nofollow" class="external text" href="https://www.aeronautics.nasa.gov/docs/chicago/noise.htm">the original</a> on 2011-10-18. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-11"><a href="#cite_ref-11">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.nasa.gov/centers/glenn/about/fs10grc.html">"Safeguarding our atmosphere"</a>. Fact Sheet. NASA - Glenn Research Center. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-Doc_9889-12"><a href="#cite_ref-Doc_9889_12-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20131214220636/http://www.icao.int/icaonet/dcs/9889/9889_en.pdf">"ICAO Airport Air Quality Guidance Manual"</a> (PDF). ICAO Guidelines. ICAO (International Civil Aviation Organisation). 2007-04-15. Archived from <a rel="nofollow" class="external text" href="http://www.icao.int/icaonet/dcs/9889/9889_en.pdf">the original</a> (PDF) on December 14, 2013. Retrieved 7 October 2011.</cite>(see <a rel="nofollow" class="external free" href="http://www.icao.int/environmental-protection/Documents/Publications/FINAL.Doc%209889.1st%20Edition.alltext.en.pdf">http://www.icao.int/environmental-protection/Documents/Publications/FINAL.Doc%209889.1st%20Edition.alltext.en.pdf</a> for updated manual.

</li>

<li id="cite_note-13"><a href="#cite_ref-13">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.virgin-atlantic.com/en/us/allaboutus/environment/biofuel.jsp">"Biofuel Flight Demonstration"</a>. Environment. Virgin Atlantic. 2008. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-14"><a href="#cite_ref-14">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20111027053159/http://www.iata.org/pressroom/airlines-international/august-2011/Pages/aircraft-recycling.aspx">"Aircraft Recycling: Life and times of an aircraft"</a>. Pressroom - Airlines International. IATA. Archived from <a rel="nofollow" class="external text" href="http://www.iata.org/pressroom/airlines-international/august-2011/pages/aircraft-recycling.aspx">the original</a> on 2011-10-27. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-15"><a href="#cite_ref-15">^</a> <cite id="CITEREFAlexandre_Gomes_de_BarrosSumedha_Chandana_Wirasinghe1997" class="citation web cs1">Alexandre Gomes de Barros; Sumedha Chandana Wirasinghe (1997). <a rel="nofollow" class="external text" href="http://my.fit.edu/~dkirk/3241/Lectures/Atrgpap.pdf">"New Aircraft Characteristics Related To Airport Planning"</a> (PDF). First ATRG Conference, Vancouver, Canada. Air Transport Research Group of the WCTR Society. Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-16"><a href="#cite_ref-16">^</a> <cite id="CITEREFSandra_Arnoult2005" class="citation web cs1">Sandra Arnoult (2005-02-28). <a rel="nofollow" class="external text" href="http://atwonline.com/airline-financedata/article/airports-prepare-a380-0309">"Airports prepare for the A380"</a>. Airline Finance/Data. ATW (Air Transport World). Retrieved 7 October 2011.</cite>

</li>

<li id="cite_note-17"><a href="#cite_ref-17">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.airsafe.com/birds.htm">"Bird hazards"</a>. Hazards. www.airsafe.com. Retrieved 12 October 2011.</cite>

</li>

<li id="cite_note-18"><a href="#cite_ref-18">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.pilotfriend.com/safe/safety/human_and_accidents.htm">"The human component in air accidents"</a>. Air Safety. www.pilotfriend.com. Retrieved 12 October 2011.</cite>

</li>

<li id="cite_note-19"><a href="#cite_ref-19">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20111216030637/http://www.navcanada.ca/ContentDefinitionFiles/publications/lak/CanadianPrairies/2-P32E.PDF">"Aviation Weather Hazards"</a> (PDF). LAKP Prairies. www.navcanada.ca. Archived from <a rel="nofollow" class="external text" href="http://www.navcanada.ca/ContentDefinitionFiles/publications/lak/CanadianPrairies/2-P32E.PDF">the original</a> (PDF) on 16 December 2011. Retrieved 12 October 2011.</cite>

</li>

<li id="cite_note-20"><a href="#cite_ref-20">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.thefreedictionary.com/airworthiness">"Airworthiness"</a>. Dictionary. The Free online Dictionary. Retrieved 2011-10-10.</cite>

</li>

<li id="cite_note-21"><a href="#cite_ref-21">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.icao.int/environmental-protection/Pages/technology-standards.aspx">"ICAO regulations"</a>. ICAO. Retrieved May 5, 2012.</cite>

</li>

<li id="cite_note-22"><a href="#cite_ref-22">^</a> <cite class="citation pressrelease cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120905175315/http://www2.icao.int/en/ism/ICAO%20Annexes/Annex%208.pdf">"Annex 8 - ICAO"</a> (PDF) (Press release). ICAO. Archived from <a rel="nofollow" class="external text" href="http://www2.icao.int/en/ism/ICAO%20Annexes/Annex%208.pdf">the original</a> (PDF) on 2012-09-05. Retrieved May 5, 2012.</cite>

</li>

<li id="cite_note-23"><a href="#cite_ref-23">^</a> <cite id="CITEREFL._JenkinsonP._SimpkinD._Rhodes1999" class="citation book cs1">L. Jenkinson; P. Simpkin; D. Rhodes (1999). Civil Jet Aircraft Design. Great Britain: Arnold Publishers. p. 55. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-340-74152-X</bdi>.</cite>

</li>

<li id="cite_note-24"><a href="#cite_ref-24">^</a> <cite id="CITEREFD._L._GreerJ._S._BreedenT._L._Heid1965" class="citation web cs1">D. L. Greer; J. S. Breeden; T. L. Heid (1965-11-18). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130408131623/http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=AD0623575">"Crashworthy Design Principles"</a>. Technical Report. Defense Technical Information Center (DTIC). Archived from <a rel="nofollow" class="external text" href="http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=AD0623575">the original</a> on April 8, 2013. Retrieved 9 October 2011.</cite>

</li>

<li id="cite_note-25"><a href="#cite_ref-25">^</a> <cite id="CITEREFDennis_F._Shanahan2004" class="citation citeseerx cs1">Dennis F. Shanahan (2004). "Basic Principles of Crashworthiness". <a href="CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.214.8052">10.1.1.214.8052</a>.</cite>

</li>

<li id="cite_note-26"><a href="#cite_ref-26">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120330161341/http://www.smartcockpit.com/data/pdfs/plane/airbus/a340/instructor/A330-A340_Overhead_Pushbuttons.pdf">"Airbus A330-A340 Overhead Panel"</a> (PDF). Data. www.smartcockpit.com. Archived from <a rel="nofollow" class="external text" href="http://www.smartcockpit.com/data/pdfs/plane/airbus/a340/instructor/A330-A340_Overhead_Pushbuttons.pdf">the original</a> (PDF) on 30 March 2012. Retrieved 9 October 2011.</cite>

</li>

<li id="cite_note-27"><a href="#cite_ref-27">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/">"Amateur Built Aircraft"</a>. General Aviation and Recreational Aircraft. FAA. Retrieved 2011-10-10.</cite>

</li>

<li id="cite_note-28"><a href="#cite_ref-28">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/19990824052440/http://www.sti.nasa.gov/tto/spinoff1997/ct11.html">"Aircraft Design Software"</a>. Computer Technology. NASA. Archived from <a rel="nofollow" class="external text" href="https://www.sti.nasa.gov/tto/spinoff1997/ct11.html">the original</a> on 24 August 1999. Retrieved 29 December 2014.</cite>

</li>

<li id="cite_note-29"><a href="#cite_ref-29">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://archive.today/20120701103526/http://adg.stanford.edu/aa241/design/optimization1.html">"Techniques for Aircraft Configuration Optimization"</a>. Aircraft Design : Synthesis and Analysis. Stanford University. Archived from <a rel="nofollow" class="external text" href="http://adg.stanford.edu/aa241/design/optimization1.html">the original</a> on 2012-07-01. Retrieved 2011-09-20.</cite>

</li>

<li id="cite_note-30"><a href="#cite_ref-30">^</a> <cite id="CITEREFJenkinsonRhodesSimpkin1999" class="citation book cs1">Jenkinson, Lloyd R.; Rhodes, Darren; Simpkin, Paul (1999). Civil jet aircraft design. p. 105. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-340-74152-X</bdi>.</cite>

</li>

<li id="cite_note-31"><a href="#cite_ref-31">^</a> <cite id="CITEREFJenkinsonRhodesSimpkin1999" class="citation book cs1">Jenkinson, Lloyd R.; Rhodes, Darren; Simpkin, Paul (1999). Civil Jet Aircraft design. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-340-74152-X</bdi>.</cite>

</li>

<li id="cite_note-32"><a href="#cite_ref-32">^</a> <cite id="CITEREFJohn_CutlerJeremy_Liber2006" class="citation book cs1">John Cutler; Jeremy Liber (2006-02-10). Understanding aircraft structures. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>1-4051-2032-0</bdi>.</cite>

</li>

<li id="cite_note-33"><a href="#cite_ref-33">^</a> <cite id="CITEREFHugh_Nelson1938" class="citation book cs1">Hugh Nelson (1938). Aero Engineering Vol II Part I. George Newnes.</cite>

</li>

<li id="cite_note-34"><a href="#cite_ref-34">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20010307121441/http://adg.stanford.edu/aa241/fuselayout/fusesection.html">"Fuselage Layout"</a>. Stanford University. Archived from <a rel="nofollow" class="external text" href="http://adg.stanford.edu/aa241/fuselayout/fusesection.html">the original</a> on 2001-03-07. Retrieved 2011-09-18.</cite>

</li>

<li id="cite_note-35"><a href="#cite_ref-35">^</a> <cite id="CITEREFTakahashi2016" class="citation book cs1">Takahashi, Timothy (2016). Aircraft Performance and Sizing, Volume I. Momentum Press Engineering. pp. 77–100. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1-60650-683-7</bdi>.</cite>

</li>

<li id="cite_note-36"><a href="#cite_ref-36">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.grc.nasa.gov/WWW/K-12/airplane/bgp.html">"Beginner's Guide to Propulsion"</a>. Beginner's Guide. NASA. Retrieved 2011-10-10.</cite>

</li>

<li id="cite_note-37"><a href="#cite_ref-37">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.pilotfriend.com/training/flight_training/wt_bal.htm">"Aircraft weight and balance"</a>. Pilot friend - Flight training. www.pilotfriend.com.</cite>

</li>

<li id="cite_note-38"><a href="#cite_ref-38">^</a> <cite id="CITEREFT.H.G_Megson2010" class="citation book cs1">T.H.G Megson (16 February 2010). Aircraft Structures (4th ed.). Elsevier Ltd. p. 353. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1-85617-932-4</bdi>.</cite>

</li>

<li id="cite_note-39"><a href="#cite_ref-39">^</a> <cite id="CITEREFJohn_D._Anderson1999" class="citation book cs1">John D. Anderson (1999). Aircraft Performance and design. McGraw-Hill. pp. 382–386. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-07-001971-1</bdi>.</cite>

</li>

<li id="cite_note-40"><a href="#cite_ref-40">^</a> <cite id="CITEREFD._Raymer1992" class="citation book cs1">D. Raymer (1992). Aircraft Design - A conceptual approach. American institute of Aeronautics and Astronautics. p. 4. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-930403-51-7</bdi>.</cite>

</li>

<li id="cite_note-41"><a href="#cite_ref-41">^</a> <cite id="CITEREFD._Raymer1992" class="citation book cs1">D. Raymer (1992). Aircraft design - A conceptual approach. American institute of Aeronautics and Astronautics. p. 5. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-930403-51-7</bdi>.</cite>

</li>

<li id="cite_note-42"><a href="#cite_ref-42">^</a> <cite id="CITEREFJohn_D._Anderson1999" class="citation book cs1">John D. Anderson (1999). Aircraft performance and Design. Mc Graw Hill. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-07-001971-1</bdi>.</cite>

</li>

<li id="cite_note-43"><a href="#cite_ref-43">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www2.deloitte.com/content/dam/Deloitte/us/Documents/manufacturing/us-manufacturing-program-management-aerospace-defense.pdf">"Program management in aerospace and defense - Still late and over budget"</a> (PDF). Deloitte. 2016.</cite>

</li>

<li id="cite_note-44"><a href="#cite_ref-44">^</a> <cite id="CITEREFCommittee_on_Analysis_of_Air_Force_Engine_Efficiency_Improvement_Options_for_Large_Non-fighter_Aircraft2007" class="citation book cs1">Committee on Analysis of Air Force Engine Efficiency Improvement Options for Large Non-fighter Aircraft (2007). <a rel="nofollow" class="external text" href="https://download.nap.edu/cart/download.cgi?record_id=11837">Improving the Efficiency of Engines for Large Nonfighter Aircraft</a>. <a href="US_National_Research_Council" class="mw-redirect" title="US National Research Council">US National Research Council</a>. p. 15. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-309-66765-4</bdi>.</cite> <code class="cs1-code">{{cite book}}</code>: <code class="cs1-code">|work=</code> ignored (help)

</li>

</ol></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><cite class="citation cs2">Egbert Torenbeek (1976), <a rel="nofollow" class="external text" href="https://www.academia.edu/14985385">Synthesis of Subsonic Airplane Design</a>, Delft University Press</cite></li>

<li><cite class="citation cs2">Antonio Filippone (2000), "Data and performances of selected aircraft and rotorcraft", Progress in Aerospace Sciences, 36 (8), Elsevier: 629–654, <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2000PrAeS..36..629F">2000PrAeS..36..629F</a>, <a href="CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.539.1597">10.1.1.539.1597</a>, <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0376-0421%2800%2900011-7">10.1016/S0376-0421(00)00011-7</a></cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.academia.edu/36508303">"Aircraft Design: Synthesis and Analysis"</a>. Desktop Aeronautics, Inc. 2001.</cite></li>

<li><cite class="citation web cs1">Dennis F. Shanahan (8 Mar 2005). <a rel="nofollow" class="external text" href="https://www.sto.nato.int/publications/STO%20Educational%20Notes/RTO-EN-HFM-113/EN-HFM-113-07.pdf">"Basic principles of Crashworthiness"</a> (PDF). <a href="NATO" title="NATO">NATO</a>.</cite></li>

<li><cite class="citation conference cs1">M. Nila; D. Scholz (2010). <a rel="nofollow" class="external text" href="https://www.fzt.haw-hamburg.de/pers/Scholz/OPerA/OPerA_PUB_DLRK_10-08-31.pdf">"From preliminary aircraft cabin design to cabin optimization"</a> (PDF). Deutscher Luft- und Raumfahrtkongress – via <a href="Hamburg_University_of_Applied_Sciences" title="Hamburg University of Applied Sciences">Hamburg University of Applied Sciences</a>.</cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20171026213619/http://www.courses.netc.navy.mil/downloads.htm?cid=1495">"Airman"</a>. Nonresident Training Courses. U.S. Navy. December 2012. Archived from <a rel="nofollow" class="external text" href="http://www.courses.netc.navy.mil/downloads.htm?cid=1495">the original</a> on October 26, 2017.</cite>

<ul><li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20161228181023/http://www.courses.netc.navy.mil/courses/14014A/14014A_ch4.pdf">"chapter 4: Aircraft Basic Construction"</a> (PDF). Archived from <a rel="nofollow" class="external text" href="http://www.courses.netc.navy.mil/courses/14014A/14014A_ch4.pdf">the original</a> (PDF) on December 28, 2016.</cite></li></ul></li>

<li><cite class="citation news cs1">Guy Norris (Mar 10, 2014). <a rel="nofollow" class="external text" href="https://aviationweek.com/blog/boeings-wonder-wall">"Boeing's 'Wonder Wall'"</a>. Aviation Week Network.</cite></li>

<li><cite class="citation web cs1">Dieter Scholz (9 July 2018). <a rel="nofollow" class="external text" href="http://www.fzt.haw-hamburg.de/pers/Scholz/HOOU/">"Aircraft Design - an Open Educational Resource"</a>. Hamburg Open Online University.</cite></li></ul>

<div class="mw-heading mw-heading3"><h3 id="Re-engine_2">Re-engine</h3></div>

<ul><li><cite class="citation news cs1">Thomas C. Hayes (November 27, 1981). <a rel="nofollow" class="external text" href="https://www.nytimes.com/1981/11/27/business/boeing-s-re-engining-worry.html">"BOEING'S 'RE-ENGINING' WORRY"</a>. NY Times.</cite></li>

<li><cite class="citation news cs1"><a href="Oliver_Wyman" title="Oliver Wyman">Oliver Wyman</a> (December 2010). <a rel="nofollow" class="external text" href="http://speednews.com/article/6950">"To Re-Engine or Not to Re-Engine: That is the Question"</a>. Aviation Week Network.</cite></li></ul></div><div><div class="zim-footer">

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