atc overview nn

Redesigning Air Traffic Control: 

Redesigning Air Traffic Control Workshop Session 1: Airspace, Procedures, and Flight Plans September 21, 2000 Michelle Eshow NASA Ames Research Center meshow@lcs.mit.edu / meshow@arc.nasa.gov

Outline: 

Outline Motivation for ATC R&D ATC Structure, Facilities Airspace Controller Roles and Responsibilities Delay Causes Flight Plans and Route Processing Challenges of Automation for ATC

Motivation for ATC Automation R&D: 

Motivation for ATC Automation R&D ATC system is already beyond its capacity. But FAA predicts that by 2010 the number of passengers will rise 59%, to 1 billion/year. Nothing on the drawing board will handle this increase. (NY Times, 09/05/00) ATC system is very complex and hard to understand, analyze, or quantify, which makes it interesting! Current level of automation is rudimentary compared with other systems (eg, aircraft flight control systems) Application of usable automation to ATC is required to meet air travel demands

National Airspace System: 

National Airspace System Handles: 63,000,000 Tower Assisted Operations Carries: 544,000,000 Passengers Over: 537,000,000,000 Revenue Passenger Miles Using: 18,700 Air Carrier A/C 170,000 General Aviation A/C Supported by: 639,000 Pilots 651,000 Non-pilots Burning: 18,000,000,000 Gallons of Fuel Generating: $87,000,000,000 Revenues Producing: $5,300,000,000 Profit In Spite of: $3,500,000,000 in Delays

FAA Statistics: 

FAA Statistics Employs: 48,000 People Including: 17,000 Air Traffic Controllers Operating: 21 Centers 194 TRACONs 476 Towers 1 Command Center Costing: $9,200,000,000 Annual Outlay

Functions of Air Traffic Management: 

Functions of Air Traffic Management Air Traffic Control: Efficiently manage traffic flow Provide flight information (weather, facility) Initiate search and rescue operations Maintain legal separation among aircraft

ATC Basics: 

ATC Basics Airline flights are under positive control at all times Control is effected by voice via radio Control is handed off from one controller/facility to another as flight proceeds across boundaries controller directs pilot to speak to next facility on a different radio frequency Communications include: speed, heading, altitude instructions (vectors) notification of other aircraft which course or runway to expect contact next facility on new frequency

ATM Tactical Information Architecture: 

ATM Tactical Information Architecture Future Controller Airline Dispatch AOC Active Controller Host Computer and ATC Information Network Flight Crew Voice ACARS Flight Plan OAG Flight Plan Voice DA’s Procedures Flight Strips, Flight Information Object Slide courtesy of Prof. J. Hansman

ATC Facilities: 

ATC Facilities Surface (“Ground”) taxiways Local Control (“Tower”) surface to ~5 nm out, 2500 ft altitude Terminal Area Control/TRACON (“Approach” or “Departure”) to ~40 nm from airport, ~15K ft altitude (inverted wedding cake) En-Route Control/ARTCC (“Center”) between, above TRACONs and everything above 18K ft Flow Control/ATC Systems Command Center centralized planning for national flow control (does not directly control flights)

Air Traffic Control System: 

Air Traffic Control System ATCT ATCT ARTCC (Center) TRACON TRACON TMU

US Airspace Sector Structure: 

US Airspace Sector Structure Slide courtesy of Prof. J. Hansman

Air Route Traffic Control Center (ARTCC): 

Air Route Traffic Control Center (ARTCC) A facility established to provide air traffic control service to aircraft operating on IFR flight plans within controlled airspace and principally during the en route phase of flight. At some airports not served by an Approach Control facility, the ARTCC provides limited approach control service. When equipment capabilities and controller workload permit, certain advisory/assistance services may be provided to VFR aircraft. Air Traffic Control Manual Order 7110.65 Pilot/Controller Glossary 21 ARTCCs 3 CERAPs (combined Center RAPCONs)

Airspace Orientation: 

Airspace Orientation FL 230 & Below Fort Worth ARTCC 18 Low Altitude Sectors

Airspace Orientation: 

Airspace Orientation FL 240 & Above Fort Worth ARTCC 15 High Altitude Sectors LBB MAF

Slide15: 

Super High Sectors High Sectors Low Sectors Approach Control FL350 and above FL240 to FL330 VFR TWR or Uncontrolled FL230 and below

Slide16: 

TRACON Video Map

Slide17: 

TRACON SECTOR DELEGATED AIRSPACE TRACON Sector Delegated Airspace

Special Use Airspace: 

Special Use Airspace Alert Area Air Traffic Control Assigned Airspace Controlled Firing Area Military Operating Area Prohibited Area Restricted Area Warning Area

Facility Organization: 

Possum Specialty Glen Rose Specialty Bowie Specialty Cedar Creek Specialty Quitman Specialty Bonham Specialty Frisco Specialty Facility Organization Fort Worth ARTCC 7 Areas of Specialization

Center Controllers: 

Center Controllers Each sector has a team of 1 to 3 controllers assigned safely and efficiently move traffic along their planned routes merge, setup flights for delivery to next facility must get/give permission to hand-off/receive aircraft In quiet periods, contiguous sectors may be combined Each Area has an Area Supervisor In Traffic Management Unit, Traffic Management Coordinators make strategic decisions about flows eg, based on weather and available runways, set TRACON arrival rates (aircraft/hour) coordinate flow parameters with adjacent facilities

ARTCC ATC Positions: 

ARTCC ATC Positions RADAR or “R” Position Assistant or ATA Position Radar Associate or “D” Position Hand-off/ Tracker Position Teamwork Flexibility Technique

Sector Workstation: 

Sector Workstation

Traffic Management Unit(with CTAS): 

Traffic Management Unit (with CTAS)

Display System Replacement (DSR) Console: 

Display System Replacement (DSR) Console

En Route Full Data Block: 

En Route Full Data Block AAL278 330C 068 500 Position Symbol Beacon Target Aircraft Identification Ground Speed Mode ‘C’ Altitude X100 Leader Line Computer Identification Number Vector Line Histories

Radar Targets/Symbols: 

Radar Targets/Symbols Flat track Free track Coast track Primary target Secondary target Correlated target Non-correlated target * # (Radar updates every 10-12 seconds)

Center Radar Display: 

Center Radar Display CO 123 350C B757 310 Slide courtesy of Prof. J. Hansman

Example Scenario: 

Example Scenario

ATM Functional Structure: 

ATM Functional Structure Slide courtesy of Prof. J. Hansman

SF Bay Area - East Flow: 

SF Bay Area - East Flow Slide courtesy of Prof. J. Hansman

SF Bay Area - West Flow: 

SF Bay Area - West Flow Slide courtesy of Prof. J. Hansman

Capacity Limit Factors: 

Capacity Limit Factors Airport Capacity Runways Gates Landside Limits Weather Airspace Capacity Airspace Design Controller Workload Demand Peak Demand Hub & Spoke Networks Environmental Limits Noise (relates to Airport) Emissions (local, Ozone, NOX, CO2) Slide courtesy of Prof. J. Hansman

Schedule Factors: 

Schedule Factors Peak Demand/Capacity issue driven by airline Hub and Spoke scheduling behavior Peak demand often exceeds airport IFR capacity (VFR/IFR Limits) Depend on bank spreading and lulls to recover Hub and Spoke amplifies delay Hub and spoke is an efficient network Supports weak demand markets Schedules driven by competitive/market factors Operations respond to marketing Trend to more frequent services, smaller aircraft Ratchet behavior Impact of regional jets Ultimately, airlines will schedule rationally To delay tolerance of the market (delay homeostasis) Limited federal or local mechanisms to regulate schedule Slide courtesy of Prof. J. Hansman

Flight Plans: 

Flight Plans Flight plans initially filed by airline give intent of aircraft (route, altitude, take-off time) are amended to reflect controller clearance changes are printed for each sector 20-30 mins before aircraft arrives printed strips arranged next to radar display in rough eta order serve as a physical reminder about aircraft controllers write clearances by hand on strips strips can be physically handed off along with aircraft flight plans critical to trajectory prediction by automation tools

Flight Plan Fields: 

Flight Plan Fields

Flight Progress Strips: 

Flight Progress Strips En Route AAL278 1 T/B722/R T468 G500 21 068 09 TXK 1930 330 DFW.\.TXK LIT J6 HVQ LDN JASEN1 IAD o AAL278 SPL FLT LIT 19 45 6262 *ZTL Type aircraft Aircraft Identification Number of times flight plan has been amended Type Equipment Filed true airspeed Ground speed Computer Identification Sector number Strip number Estimated Time at fix Fix posting for Sector 21 Altitude Coordination fix time Previous fix Coordination Symbol to adjacent ATC facility Beacon code Route of flight Remarks section Control Symbology Red/Black Strip Marking TCAS Equipped

Slide37: 

Standard Instrument Departure (SID) (Pilots hard copy)

Highways of the Sky (Airways): 

Highways of the Sky (Airways) DFW LIT MEM CHA SPA GSO IAD J66 J66 J118 J118 J14 J14 (Direct) Jet Routes FL180 Victor Routes FL180 V124

Standard Terminal Arrival Route: 

Standard Terminal Arrival Route IAD Depart HDG 190 Expect RV to Final Turbojets expect clearance to Cross at 11,000’ at 250kts HVQ 072 BKW 095 DILNN FINKS 079 R-259 AML LDN R-206 JASEN GILBY R-300 DOCCS “AAL278, Reduce speed to TWO ONE ZERO, Contact Dulles Approach ONE TWO ZERO POINT FOUR FIVE.” “AAL278, Reducing and switching, Good Day.” Requested Route Turbojets Expect Clearance to Cross at FL240 Jasen One Arrival Charleston Transition

Flight Plan Routes: 

Flight Plan Routes Helpful hints DFW.DALL5.TXK..LIT.J131.PXV.J29.JHW.J82.ALB.GDM2.BOS 4 letters + 1 number: SID or STAR (TRACON route) 3 letters: waypoint (also indicates VOR nav aid) J + number: jet route (V + number: victor/vfr route) “..” separates 2 like elements (ABC..DEF) “.” separates 2 un-like elements (ABC.J52) Some variations: Other waypoint types: lat/long, x/y, radial/distance: 47N/121W, 437/248, DFW300040 SJC./.TXO..SJT.CUGAR6.IAH Will enter ZFW at TXO; don’t need to see earlier part of route

Domain Challenges of ATC Automation: 

Domain Challenges of ATC Automation Control techniques very different for different facilities (Center, TRACON, Tower…) Even among same-type facilities, procedures vary widely (Chicago Center vs Ft. Worth Center) Airspace description data not always easily parsed Electronic system outputs do not always reflect reality Every rule has exceptions Difficult/costly to change procedures at the moment new tools are introduced (need fallback position) Lots of politics among FAA, unions, airlines...