Aircraft Classifications. Dr. Antonio Trani and Julio Roa Department of Civil and Environmental Engineering.

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Aircraft Classifications Dr. Antonio Trani and Julio Roa Department of Civil and Environmental Engineering. January 2018 1

Material Presented The aircraft and the airport Aircraft classifications Aircraft characteristics and their relation to airport planning Large capacity aircraft impacts 2

Relevance of Aircraft Characteristics Aircraft classifications are useful in airport engineering work (including terminal gate sizing, apron and taxiway planning, etc.) and in air traffic analyses Most of the airport design standards are related to aircraft size (i.e., wingspan, aircraft length, aircraft wheelbase, aircraft seating capacity, etc.) Airport fleet compositions vary over time and thus is imperative that we learn how to forecast expected vehicle sizes over long periods of time The Next Generation (NextGen) air transportation system will have to accommodate to a more diverse pool of aircraft 3

Airport Engineering and Aircraft Characteristics Important to know the performance aspects of the aircraft on the ground (low taxiing speeds) as well as on takeoff and landing Boeing 737-800 Landing at Runway 36L in Charlotte (A.A.Trani) 4

Web Sites to Learn to Recognize Various Aircraft Pictures taken by the author at various airport (https:// photos.app.goo.gl/8bdsvdwpqu7lhidi2) Airliners site airliners.net Jetphotos (https://www.jetphotos.com) Aerospatiale ATR-42-500 Airbus A380-800 5

ICAO - International Civil Aviation Organization Provides guidance about airport design in all countries of the World FAA design standards and ICAO standards are trending to the same values with time ICAO Documents 9157 - Aerodrome Design Manual 6

ICAO Aerodrome Reference Code Code Element 1 ICAO Aerodrome Reference Code used in Airport Design Code Number Aeroplane Reference Field Length (meters) 1 Less than 800 2 800 but less than 1200 3 1200 but less than 1800 4 More than 1800 7

ICAO Aerodrome Reference Code Code Element 2 ICAO Aerodrome Reference Code used in Airport Geometric Design Design Group Wingspan (m) Outer Main Landing Gear Width (m) Example Aircraft A < 15 < 4.5 All single engine aircraft, Some business jets B 15 to < 24 4.5 to < 6 Commuter aircraft, large business jets (EMB - 120, Saab 2000, Saab 340, etc.) C 24 to < 36 6 to < 9 Medium-range transports (B727, B737, MD-80, A320) D 36 to < 52 9 to < 14 Heavy transports (B757, B767, MD-80, A300) E 52 to < 65 9 to < 14 Heavy transport aircraft (Boeing 747, A340, B777) F 65 to < 80 14 to < 16 A380, Antonov 225 8

Federal Aviation Administration Runway Design Code (RDC) Combines three classification criteria to define the design specifications of each runway of the airport: Aircraft Approach Code (AAC) Aircraft Design Group (ADG) Approach visibility minimums A fourth classification - called Taxiway Design Group (TDG) is also used in airport design The following slides provide some insight about each classification scheme Note: An airport may have different RDC standards for different runways For example, a runway used for air carrier operations may use a higher RDC standard than a runway used for General Aviation Operations 9

Example: Baltimore-Washington International (BWI) Runway 33 Used by General Aviation aircraft Runway 28 Used by air carrier aircraft source: Google Earth 10

Federal Aviation Administration Aircraft Design Group (ADG) Design Group Tail Height (feet) Wingspan (feet) Representative Aircraft Types I < 20 < 49 Cessna 172, Beech 36, Cessna 421, Learjet 35 II 20 to < 30 49 to < 79 Beech B300, Cessna 550, Falcon 50, Challenger 605 III 30 to < 45 79 to < 118 Boeing 737, Airbus A320, CRJ-900, EMB-190 IV 45 to < 60 118 to < 171 Boeing 767, Boeing 757, Airbus A300, Douglas DC-10 V 60 to < 66 171 to < 214 Boeing 747, Airbus A340, Boeing 777 VI 66 to < 80 214 to < 262 Airbus A380, Antonov 225* * The Antonov 225 has a wingspan of 290 feet (in a class by itself). Only one aircraft produced. 11

Federal Aviation Administration Aircraft Design Group (ADG) Note: Always use the most critical dimension of the two criteria shown in Table 1-1 source: Table 1-2 of FAA AC 150/5300-13A 12

FAA Aircraft Approach Speed Classification (AAC) Airport Terminal Area Procedures Aircraft Classification (FAA Scheme) Group a Approach Speed (knots) Example Aircraft b A B C D E < 91 91 to < 121 121 to < 141 141 to < 166 >= 166 All single engine aircraft, Beechcraft Baron 58 Business jets and commuter aircraft (Beech 1900, Saab 2000, Saab 340, Embraer 120, Canadair RJ, etc.) Medium and short range transports (Boeing 727, B737, MD-80, A320, F100, B757, etc.) Heavy transports (Boeing 747, A340, B777, DC-10, A300) BAC Concorde and military aircraft a. At maximum landing weight b. See Appendix 1 in FAA Advisory Circular 150/5300-13A for a complete listing of aircraft approach speeds 13

FAA Aircraft Approach Speed Classification (AAC) source: Table 1-1 of FAA AC 150/5300-13A Aircraft approach speeds are taken at maximum allowable landing weight For the same aircraft, approach speeds vary by weight For typical commercial aircraft, approach speeds can vary as much as 15-20 knots between maximum landing weight and empty operating weight) 14

Example of Aircraft Approach Speed Variations Consider the Airbus A340-500 - a long-range aircraft Approach Speed (knots) Max. Allowable Landing Weight 300,000 kg Approach speed at 180,000 kg landing weight ~ 125 knots Approach speed at 300,000 kg landing weight (maximum allowable landing mass) ~ 160 knots source: Airbus A340-500 Airplane Characteristics for Airport Planning 15

Source to Find Aircraft Approach Speed and Aircraft Mass (weight) Data FAA Advisory Circular AC/150 5300-13 Airport Design (Appendix I) 16

Presentation of Aircraft Characteristics in Appendix I of AC 150/5300-13A Table A1-1. Aircraft characteristics database - sorted by aircraft manufacturer model Aircraft Approach Class Aircraft Design Group Taxiway Design Group 17

Approach Visibility Minimums Defined by a parameter called Runway Visual Range (RVR) RVR is the range over which the Pilot of an aircraft on the centre line of a runway can see the runway surface markings or the lights delineating the runway or identifying its centre line. (ICAO) RVR Equipment 18

Approach Visibility Minimums source: Table 1-3 of FAA AC 150/5300-13A Instrument Landing System Categories 19

Recap: Runway Design Code (RDC) Three parameters are combined to derive a so-called Runway Design Code (RDC) AAC, ADG and Approach Visibility Minimums RDC provides three parameters needed to determine design standards for an airport Note: for most airport design projects the TDG parameter is also critical to determine taxiway-to-runway distances 20

Taxiway Design Group (TDG) Previous FAA guidance considered tail height and wingspan as design factors for geometric design New guidance implemented in September 2012 considers: - Dimensions of the aircraft undercarriage - Main gear width (MGW) - Cockpit to main gear dimensions (CMG) 21

FAA AC 150/5300-13A Appendix I Figure A1-1. Typical dimensions of large aircraft 22

FAA AC 150/5300-13A Appendix I Figure A1-2. Typical dimensions of small aircraft 23

CMG Distance vs Wheelbase Distance FAA specifies: Cockpit to Main Gear (CMG) dimension will be used instead of the aircraft wheelbase for aircraft where the cockpit is located forward of the nose gear (typically applies to commercial aircraft) For aircraft with the cockpit located aft of the nose gear, use the wheelbase instead of CMG to determine the Taxiway Design Group (TDG) See figures in the previous slides 24

Examples : Small Aircraft Many general aviation aircraft (called GA) typically have the nose gear located in front of the cockpit (use the wheelbase distance for design) Cirrus SR-20 4-seat single engine piston power aircraft Cessna Citation Excel 560XL Twin turbofan powered aircraft 25

Examples - Commercial Aircraft Most commercial aircraft have the cockpit located ahead of the nose gear (use CMG distance) Airbus A320.Twin-engine turbofan powered, commercial aircraft Cockpit to Main Gear Distance (CMG) 26

Special Landing Gear Configurations Some aircraft have special landing gear configurations Piper J-3 Cub 2-seat single engine piston power aircraft Tail Dragger Configuration c BAC Concorde - Supersonic Transport (very long CMG distance) 27

Taxiway Design Group Definitions Figure 4-1. Taxiway Design Groups (TDGs) source: FAA AC 150/5300-13A 28

Aircraft Characteristics Databases FAA site http://www.faa.gov/airports/ engineering/aircraft_char_database/ Our website, excel file http:// 128.173.204.63/courses/ cee4674/cee4674_pub/ aircraft_char_122009.xls http://www.faa.gov/airports/ engineering/ aircraft_char_database/ Eurocontrol site http://elearning.ians.lu/ aircraftperformance/ 29

Sample Excel Database of Aircraft Characteristics Available at: Excel file with aircraft data http://128.173.204.63/courses/ cee4674/ cee4674_pub/aircraft_char_1_2017.xls http://www.faa.gov/airports/engineering/ aircraft_char_database/ 30

Example Problem #1 An airport is to be designed to accommodate the Boeing 757-300 aircraft. Determine the airport reference code and the taxiway design group to be used. Solution: Look at the FAA aircraft database:approach speed is 143 knots (AAC = D) and Wingspan is 124.8 feet and tail height 44.9 feet (thus group IV) 31

Picture the Aircraft in Question (Sanity Check) Boeing 757-300 taking off at Punta Cana International Airport (A.Trani) Aircraft pictures are available at: http://www.airliners.net 32

Example Problem #1 Boeing 757-300 :Approach speed is 143 knots (AAC = D) and Wingspan is 124.8 feet and tail height 44.5 feet (belongs to ADG group IV) Boeing 757-300 Belongs to Group IV Reason: tail height falls into III group, wingspan belongs to group IV Use the most critical Note: The most critical element for this aircraft is the wingspan (tail height fits into III) 33

Example Problem #1 Boeing 757-300 has a wheelbase of 73.3 feet, a Main Gear Width of 28.2 feet (8.6 meters) and a Cockpit to Main Gear distance of 85.3 feet (26 m) Boeing 757-300 Belongs to Taxiway Design Group (TDG) 4 34

Example Problem #1 Boeing 757-300 has a wheelbase of 73.3 feet, a Main Gear Width of 28.2 feet (8.6 meters) and a Cockpit to Main Gear distance of 85.3 feet (26 m) Boeing 757-300 Belongs to Taxiway Design Group (TDG) 4 35

Boeing 757-200/300 Document for Airport Design Aircraft Manufacturer documents provide another source of aircraft data 36

Example Problem #2 An airport is to be designed to accommodate the Airbus A330-300 aircraft. Determine the ICAO airport reference code element 2 to be used in design. Solution: Look at the aircraft characteristics provided by Airbus 37

Example Problem #2 Solution: The aircraft wingspan is listed at 60.3 meters Outer main gear width is 11.3 meters Aircraft belongs to ICAO Code E 38

Picture the Aircraft in Question (Sanity Check) Airbus A330-300 landing at Charlotte Douglas International Airport (A.Trani) Aircraft pictures are available at: http://www.airliners.net 39

Wake Vortex Every aircraft generates wakes behind the wing due to the strong circulation required to generate lift Circular Strenght Boundary Wake vortices depend on aircraft mass, wingspan and atmospheric conditions 40

Legacy Wake Vortex Classification Final Approach Aircraft Wake Vortex Classification Superheavy 41

RECAT Wake Vortex Classification FAA Introduced a new re-categorization (RECAT) procedure at Memphis International Airport in 2012 FAA Order N JO 7110.608 42

RECAT Wake Vortex Classification The new Re-Categorization standards have been developed by FAA and ICAO Aircraft groups have changed! A = Superheavy aircraft, F = small aircraft Wake Turbulence Separation for Approach A A Follower B C D E F 5 MN 6 MN 7 MN 7 MN 8 MN B 3 MN 4 MN 5 MN 5 MN 7 MN Leader C D 3.5 MN 3.5 MN 6 MN 5 MN E 4 MN F 43

RECAT Phase 1 Wake Vortex Classification Source: Tittsworth, et al., 2012 Wake Turbulence Program- Recent Highlights 44

RECAT Phase 1 Wake Vortex Classification RECAT Class Representative Aircraft Picture of Representative Aircraft A Airbus A380-800 B C Boeing 747-400, Boeing 777-300ER, Airbus A330-300, Airbus A350-900, Airbus A300-600, Boeing 787-8/9 McDonnell Douglas DC-10, Boeing MD-10, Boeing Douglas MD-11, Boeing 767-300 D Boeing 757-200 and -300, Boeing 737-800, Airbus A320, Airbus A321, McDonnell Douglas MD-80, Embraer 190, Bombardier CS-300, Gulfstream 550 and 650 E Bombardier CRJ-900, Embraer 170/175, Bombardier CRJ-700, Embraer 145, Bombardier CRJ-200, Dassault Falcon 7X F Cessna CitationJet 4, Gulfstream G280, Bombardier Challenger 350, Cessna 182, Cessna 172 45

Example Problem #3 Find the RECAT Phase 1 for the Boeing 757-300 with winglets Solution: Look at the FAA aircraft database: Wingspan is 134.8 feet and Maximum Takeoff Weight (MTOW) is 270,000 lb. Look at the flowchart presented to find that the Boeing 757-300/W belongs to RECAT class D 46

International Air Transport Association (IATA) Classification Used in the forecast of aircraft movements at an airport based on the IATA forecast methodology. 47

Other Classifications that You Will Read About in Trade Magazines Aircraft classification based on the aircraft use General aviation aircraft (GA) Corporate aircraft (CA) Commuter aircraft (COM) Transport aircraft (TA) Short-range Medium-range Long-range 48

General Aviation Aircraft Typically these aircraft can have one (single engine) or two engines (twin engine). Their maximum gross weight is below 14,000 lb. 49

Corporate Aircraft Typically these aircraft can have one or two turboprop driven or jet engines (sometimes three). Maximum gross mass is up to 40,910kg (90,000 lb) 50

Commuter Aircraft Usually twin engine aircraft with a few exception such as DeHavilland DHC-7 which has four engines. Their maximum gross mass is below 31,818kg (70,000 lb) 51

Short-Range Transport Aircraft Certified under FAR/JAR 25. Their maximum gross mass usually is below 68,182kg (150,000 lb.) 52

Medium-Range Transport Aircraft These are transport aircraft employed to fly routes of less then 3,000 nm (typical). Their maximum gross mass usually is below 159,090kg (350,000 lb.) 53

Long-Range Transport Aircraft These are transport aircraft employed to fly routes of more than 3,000 nm (typical). Their maximum gross mass usually is above 159,090kg (350,000 lb.) 54

Aircraft Trends Very large capacity aircraft (NLA or VLCA) Airbus A380 and Boeing 747-8 New generation long-range transport Boeing 787 and Airbus A350 New generation short range aircraft Bombardier C-Series, Mitsubishi Regional Jet (MRJ), Comac 919 and Irkut MC-21 55

Very Large Capacity Aircraft (NLA/VLCA) Airbus A380 was introduced into service in 2008 Boeing 747-8 was introduced in 2012 A380-800 at LAX Airport (A.Trani) 56

Tradeoffs in the Design of Aircraft Aircraft designed purely on aerodynamic principles would be costly to the airport operator yet have low Direct Operating Cost (DOC) Aircraft heavily constrained by current airport design standards might not be very efficient to operate Adaptations of aircraft to fit airports can be costly Some impact on aerodynamic performance Weight considerations (i.e., landing gear design) Tradeoffs are needed to address all these issues 57

Impacts of Very Large Capacity Aircraft Large capacity aircraft requirements Airside infrastructure impacts (taxiways and runways) Runway capacity impacts Airport terminal impacts (gates and aprons) Pavement design considerations Noise considerations 58

Very Large Capacity Aircraft: Airbus A380-800 Source: Airbus 59

Comparative Size of Airbus A380 and Other Heavy Aircraft Source: Airbus and Boeing documents for airport planning. *Estimated by author 60

Aircraft Wing Aspect Ratio (AR) AR = b 2 / S AR wing aspect ratio (dimensionless) S b 2 wingspan (ft2 or m 2 ) S wing area (ft 2 or m 2 ) b 61

Evolution of Aircraft Wing Aspect Ratio Long range aircraft require very long and thin wings to be aerodynamically efficient Wing Aspect Ratio Year in Revenue Service 62

Evolution of Aircraft Mass and Wingspan 63

Very Large Capacity Aircraft Runway and Taxiway Requirements Very large capacity aircraft require wider runways and wider taxiways A380 on ADG VI Runway A380 on ADG VI Taxiway 64

Large Capacity Aircraft Require Larger Maneuvering Envelopes 65

Airport Terminal Impacts Large capacity aircraft require more complex gate interfaces to expedite the enplaning/ deplaning of passengers Terminal Dual-level Boarding Gates Two-level configuration Terminal Airbus A380 (A.A. Trani) Dual-level Boarding Gates Upper and lower deck doors 66

Capacity Impacts of Very Large Capacity Aircraft Operations Runway capacity is influenced by larger in-trail separations (i.e., reduction in runway capacity) Airport terminal volume requirements could increase due to the larger size of the aircraft (up to 850 passengers in a single class configuration) 67

Runway Capacity Impact Analysis The diagram shows that large capacity aircraft can reduce the runway hourly capacity of the airport Percent VCLA Parallel Runway Configuration IMC Weather Conditions (aircraft/hr) Independent Parallel Approaches Departure Saturation Capacity (aircraft/hr) 68

Airport Pavement Design Impacts Very large capacity aircraft have complex landing gear configurations that require careful analysis to understand their impacts on airport pavements Pavement Thickness (cm) Landing Gear Configuration Quadruple + Triple-in-Tandem CBR Value 69