Description of the National Airspace System Dr. Antonio Trani and Julio Roa Department of Civil and Environmental Engineering Virginia Tech
What is the National Airspace System (NAS)? A very complex system made up of airports, airway routes (like highways in the sky), airlines and people (air traffic controllers, pilots and the flying public). In the National Airspace System (NAS) there are 60,000 flights controlled by Air Traffic Control services every day (>35,000 performed by airlines). Air Traffic Control in NAS handles more than 22 million flights per year. More than 94 million passengers arrive or depart Atlanta International Airport in a year. Atlanta Hartsfield Intl. airport handled more than 952,000 operations in 2012 (FAA 2012). 2
Flowchart of the National Airspace System (NAS) People (>430,000) Fleet (>202,034) Plots (>600,000) Aircraft Manufacturers General Aviation National Airspace Landing Facilities (20,103) Air Traffic Control Airport Infrastructure Airport People Airlines ATC Infrastructure ATC People (51,000) Fleets (>6,700) People (>400,000) 3
NAS Traffic and Asset Characteristics Airport Transportation Demand Activity in the National Airspace System Parameter Year 2014 Remarks Number of Annual Operations at 516 FAA towers Domestic Passenger Emplanements (per year) International Passenger Emplanements (per year) Number of Air Carrier Aircraft in the US 49,000,000 FAA 2014 Forecast 654,000,000 FAA 2014 Forecast 85,100,000 FAA 2014 Forecast 6,727 Includes 760 cargo aircraft Number of GA Aircraft 209,034 FAA 2014 Forecast Annual Hours Flown by Air Carriers Annual Hours Flown by GA Aircraft 15,600,000 Estimated 24,000,000 Declined in the last 10 years 4
US Domestic Enplanements Source: FAA 2014 Aerospace Forecast Passenger Enplanements Enplanement = One passenger boarding at an airport Observations: 1) The highest number of enplanements was recorded in the year 2007 before the economic recession 2) System is recovering but slowly 3) International travel is up 5
US International Enplanements Source: FAA 2014 Aerospace Forecast Passenger Enplanements (millions) 90 68 45 23 70.8 71.6 75.3 78.3 73.6 77.4 81 82.9 85.1 0 2005 2006 2007 2008 2009 2010 2011 2012 2013 Observations: 1) The economic recession had an impact on international travel (less money for discretionary travel) 2) Foreign international travelers helped reverse the trend 3) International enplanements could reach 134 million in the year 2022 of all travel in the US in 2024 6
US Domestic Cargo Markets Source: FAA 2014 Aerospace Forecast Cargo Revenue (Ton- Miles) RTM = Revenue Ton- Mile Observations: 1) Cargo has been hit hard by the economic recession 2) System recovered somewhat in the period 2010 to 2012 3) Cargo carriers moved deliveries to ground transportation modes due to high Jet- A fuel prices in the period 2010-2012 7
US Airline Fleet Observations: 1) Cargo fleet has decreased by 25% since year 2005 2) Mainline fleet has remained stable (- 3% change) 3) Regional fleet has decreased by 25% since year 2005 Airlines have been very cautious to add capacity (i.e., seats) Source: FAA 2014 Aerospace Forecast Airline consolidation results in higher passenger load factors (number of seats used in every flight) 8
FAA Future Passenger Demand Projections If present economic trends persist: Passenger Enplanements Source: FAA 2014 Aerospace Forecast 1) Passenger boardings system- wide (domestic + international) could reach 1,000 million by 2027 2) According to the FAA forecast, both mainline and regionals are expected to grow Commercial passenger demand is very sensitive to economic factors Airlines will add aircraft to the system if the demand grows per FAA forecasts In the past the FAA forecasts have been a bit optimistic due to optimistic assumptions of the economic factors used in the forecast 9
Why is the National Airspace System Important? Many people travel by air every day (more than 2 million passengers per day) The economy of the country depends on a reliable and safe air transportation system Air transportation is the most economical way to travel over long distances (i.e., 1,000 kilometers or more) More than eight million people in the U.S. work in this industry directly or indirectly (supporting the air transportation sector). 10
Airports in the US There are 20,103 landing facilities in the U.S. There are more than 3,400 public airports with at least a paved runway equal or greater than 3,000 ft. There are thousands of private airport facilities. Today, 84% of the passengers using the National Airspace System (NAS) use the top 55 airports in the U.S. In 1989, 77% of the passenger traffic used the top 55 airports in the U.S. The Federal Aviation Administration considers 3,200 airports critical to the aviation system (NPIAS). 11
Airports in the US There are 20,103 airports (public and private) in the U.S. Each dot in this graph is an airport Some airports in Canada are also shown 12
Airports in the Commonwealth of Virginia There are 583 airports (public and private) in the State of Virginia Blacksburg 13
National Plan for Integrated Airports (NPIAS) Airports considered important to FAA (3,300 airports) These airports are eligible for Federal funding 14
Some Airport Statistics The top 100 airports in the United States, as measured by 2013 passenger enplanements, accounted for almost 97 percent of the 726 million passengers in the U.S. More than 94 million passengers arrived or departed from Atlanta Hartsfield Airport in 2012. By 2040, aircraft operations at the top 100 airports are projected to increase by 57 percent. There is an obvious need for engineers to maintain and develop plans and designs for new facilities (i.e., new airports and airport improvements). 15
Runway Statistics (NAS Airports) A total of 24,356 runways in the NAS (includes helipads) There are 11,490 paved runways in the NAS (includes helipads) Some overlap exist in the data 333 runways are listed as asphaltconcrete US has the largest number of runways in the World Number of Runways in the NAS 11000 8250 5500 2750 0 7,464 4,364 10,402 Includes helipads 820 905 Asphalt Concrete Turf Gravel Dirt Source: FAA Landing Facilities Database 16
Runway Length Statistics (NAS) The average runway length for asphalt runways is 4,340 feet (with helipads removed) Concrete runways average 6,323 feet if helipads are removed Most private airports have runways made up of turf, gravel or dirt Average Runway Length (ft) 7000 5250 3500 1750 4,340 6,323 2,201 2,686 2,702 0 Asphalt Concrete Turf Gravel Dirt Source: FAA Landing Facilities Database 17
Distribution of Runway Lengths Paved runways length distribution (NAS-wide) 1800 1500 1,536 1,574 Source: FAA Landing Facilities Database Number of Runways 1,312 1200 900 600 624 614 300 0 84 3000 2000 1000 6000 5000 4000 341 227 138 123 57 7000 8000 9000 10000 12000 11000 60 22 14000 13000 6 7 16000 15000 1 Runway Length (ft) 18
Passenger Boardings at US Commercial Airports There are about 450 commercial airports in the continental US 50 Enplanements (Millions of Boardings per Year) 38 25 13 0 45 32 32 29 25 25 MCO MIA IAH PHX CLT LAS SFO JFK DEN DFW LAX ORD ATL 21.4 20.85 19.6 19.5 18.8 19.1 17.7 16.92 Traffic at Top 30 commercial airports in 2013 source: FAA 2014 Aviation Forecast data Enplanement = One passenger boarding at an airport EWR Airport TPA SAN HNL DCA MDW SLC IAD BWI FLL LGA BOS PHL DTW MSP SEA 17.9 16.5 17.1 14.7 14.5 13.3 11.0510.97 10.6 9.63 9.72 9.83 9.5 8.81 8.24 19
Airways : Highways in the Sky Most operations in the NAS still use routes supported by VORs Blacksburg Flight Plan: Blacksburg (BCB) to Miami (MIA) Typical VOR Installation Gulf of México source: skyvector.com Miami 20
Airways : Like Highways in the Sky Most operations in the NAS still use routes supported by VORs New York (JFK) Los Angeles (LAX) Flight Plan: New York Kennedy (JFK) to Loas Angeles (LAX) Gulf of México source: skyvector.com 21
Origin-Destination Flown by Boeing 737-800 in the NAS (year 2014 Data) OD airport pairs with flights by Boeing 737-800 aircraft Flights to Alaska and Hawaii are included in the plot 1,054 flights daily on average by B738 Average flight distance = 1,074 statute miles 22
Origin-Destination Flown by Airbus A320 in the NAS (year 2014 Data) OD airport pairs with flights by Airbus A320 aircraft Flights to Alaska are included in the plot 1,420 flights daily on average by Airbus A320 Average flight distance = 1,209 statute miles 23
Airline Market Share Airlines have been very structured in only adding capacity in markets that need more seats Below are airline market shares nationwide 18 16.8 16.7 15.2 Recently Merged 14.3 14 12.5 US Market Share (%) 9 8.4 5 5.1 4.2 2.4 2.3 2.1 0 Delta Southwest United American US Airways JetBlue Alaska ExpressJet SkyWest Spirit Other US Airline 24
Airline Fares Nationwide (in current dollars) Airlines have been very cautious by only adding capacity in markets that need more seats Below are airline fares nationwide Average Air Fare (current $) 400 300 305 307.31 328.55 328.3 346.4 310.35 336.5 363.85 374.83 383.3 200 100 0 2004 2005 2006 2007 2008 Year 2009 2010 2011 2012 2013 25
Average Air Fare ($2013) Airline Fares Nationwide (in 2013 dollars) When discounted for inflation, air fares have not increased appreciably in the last decade (except during the 2008 recession) The average distance flown has not changes appreciably 400 376 366 378 369 375 359 378 379 383.3 337 300 200 100 0 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Year 26
Why Learn About NAS Operations? To understand this complex system (how airports, flights, and air traffic controllers interact). To plan and design new airport/airspace infrastructure. Airports are very expensive (12 billion dollars were invested in Kansai airport in Japan) Air traffic services cost 9 billion dollars every year in the U.S. alone To improve the safety of the system (i.e., to reduce midair collisions and accidents). To improve the capacity of the system (i.e., to handle more flights or operations without building more airports). 27
Airports are Complex Intermodal Transportation Facilities Dulles International Airport Airport Landside Ground vehicles and passengers Airport Terminal Passenger flows Airport Airside Aircraft movements 28
Modeling Approach to NAS Operations We use computer simulation models to replicate the real system (i.e., airports, aircraft, airways, sectors, etc.) Simulation models are mathematical abstractions on how the system works Simulation models have a lot of logic and math behind them Computer simulations integrate mathematics and computer science expertise. Air traffic control and aircraft simulators are sometimes linked via high-speed networks to design changes to NAS without risking lives. Hard work and a lot of patience is what it takes to model airport and airspace operations. 29
Important Agencies for Airport Engineers FAA - regulates and promotes aviation in the US ICAO - International Civil Aviation Organization Based in Montreal, Canada Part of the UN charter Promotes and oversees aviation activities in the world State Departments of Aviation Promote aviation development in individual states Normally part of State DOTs (Virginia has a separate entity called Department of Aviation) Airport Authorities Promote development at the local level Individual or multiple airports 30
Federal Aviation Regulations Most air transportation activities are carried out using Federal Aviation Regulations (FAR) FAR 23 and 25 (Certification of aircraft) FAR 121 (Operation of aircraft by air carriers) FAR 77 (Obstructions to navigation) FAA provides designers and planners with Advisory Circulars (AC) to guide airport planning and design activities AC 150/5060-5 (Airport Capacity and Delay) AC 150/5300-13 (Airport Design) The regulations are quite strict and enforced. The FAA provides guidelines to even how install a light fixture on a taxiway. FAA Terminal Operation Procedures (TERP) 31
Things to Read The following is a partial list of magazines and journals that I recommend reading if you like to know more about airports. Airports of the World (monthly) (http://www.airportsinternational.com) Aviation Week and Space Technology (weekly) (http:// aviationweek.com) Business and Commercial Aviation (monthly) (http://aviationweek.com/ business-aviation/bca) Air Transport World (monthly) (http://atwonline.com) Airliner World (monthly) (http://www.airlinerworld.com) Journal of Air Traffic Control (quarterly) Transportation Research (monthly) 32