MITRE-CAASD’s systemwide Modeler State and Near-Term Plans

1. MITRE-CAASD’s systemwideModelerState and Near-Term Plans Pete Kuzminski 10 December 2008

2. System-wide Analysis Framework GADS Load Input Convert to .itin format Adaptation ATO-P Demand File DB Airframes File Load Output CRCT TM Itinerary File GRASP Itinerary File (adjusted) Query Flight Info Load Value Added Tables Add flight info, VFR, & adjust Taxi Times Itinerary File Link Flights ETMS ASQP Performance Metric Analysis Visualization Transits File Trajectories File Scenario Generation 4-D Trajectory Modeling Airframes File (revised) Itinerary File (revised) Generate Background Files Equipment Airspace systemwideModeler Annualization Airports Fixes Post Processing ARTCCs Operators MIT TSSIM Airframe TRACON Sectors Sector Schedule Sector Airport Corridor GDP TRACONs systemwideModeler Resources Background Files

3. Analysis and Visualization Tools

4. Recent Applications • Benefits assessment • Data Communications Segment 1 • NextGen Implementation Plan • Problem identification • Future Airport Capacity Task (FACT) • Future Airspace Capacity and Efficiency Study (FACES)

5. Model Purpose To estimate the aggregate and network effects of changes to the NAS • Delay and load are primary metrics of interest • By phase of flight • By element, e.g., airport, sector, system • Because output is as-flown trajectories, • other effects could be interpreted, e.g., fuel burn • Demand: volume, fleet mix • Capacity: airport, TRACON, sector, fixes and airways • Structure: airspace and routes • Traffic management • Time- vs. distance-based • First-come first-served vs. other priority policies

6. systemwideModeler • Latest in NASPAC/DPAT/MLM lineage • Designed and first released in 2006 Flights Transits Trajectories Background Airports Sectors etc. Output Flight events Resource events Simulation engine Resources (including capacities) • Written in SLX, a PC-based simulation language • Active, disciplined CAASD development effort • ~30k lines of code • Scenario runs in 5-15 minutes

7. plans plans plans plans plans constraints Model Approach Flights Resources • Start with initial 4D • trajectories (from • external trajectory • model) • Change plans to • respect constraints • Characterize “use” • by flights • Monitor flight plans/progress • Regulate resource • “condition”, e.g., occupancy • Issue constraints to • individual flights Flights’ only response to constraints is to delay passage of points. (Cancellations, re-routing, and altitude changes are responses being researched.) A resource only constrains a flight once it enters a planning horizon. 7

8. AirportTactical Separation frontier of feasible throughput • Sensitive to: • runway layout and use • standard procedures • separation rules and minima • variability and buffers • fleet mix • aircraft performance • Capacities scheduled by: • weather • winds • ceiling • configuration selection rules hourly arrivals hourly departures • Arrivals • Spacing enforced to maintain arrival priority rate • Departures • Spacing enforced to maintain feasible throughput over user-specified period          Arrivals . . .        Departures t-x t ready time 8

9. AirportDemand Management Airport Demand Manager Enforcement Mechanisms Anticipates demand Anticipate landing/takeoff times AAR/ADR A A A A A A A A A A A D D D D D D D D Ground/Departure Gateways Delay pushback Picks operating points arrs Arrival Gateway Delays arrival TRACON entry or Merging and Spacing dpts Spreads delay Publishes rates AAR ADR

10. SectorOccupancy Limited • Capacities typically MAP value or some transformation • May change on schedule • Airspace assigned to sectors may also change on schedule • Sector entries are delayed • Uses several “services” available to resources • Avoids cycling • Relieves resource developers of several burdens • Allows developers to focus on characterizing use and anticipating conditions 6   1 9  8   2 A 7   3  4 10  B  5

11. SectorWorkload Limited • As flight approaches sector, its nature and activity in • the sector is evaluated • Commercial flight? GA? Military? Equipage? • Previous/next sectors? • Transitioning altitude? • Requires spacing for arrival airport? • Involved in aircraft-aircraft conflict?      flight workload • Modeled workload distributed over transit of flight • Handoff and coordination tasks • Monitoring and spacing • Conflict detection and resolution • Delay absorption t Entry Exit sector workload threshold • Flight’s entry delayed until addition of modeled workload • to sector’s anticipated workload acceptable • 15-minute moving sum of workload is governed t delayed entry • When resource informed of changes to plan, • it updates workload as appropriate • For example, delayed exit causes additional work t change notification Entry Exit

12. Other Resources • Arrival and departure TRACON • Miles-in-trail restrictions • Ground Delay Programs/Ground Stops • Airframes

13. Near-Term Work • Improved ground gateway • More strategic traffic management for en route congestion • Departure fix congestion • Dynamic assignment of airframes and cancellations • Arrival TRACON • Better representation of routes • Reduced acceptance in presence of load and delay • Reduced variability of final approach fix delivery • Demand scenario generation • To address variability in demand and airport configurations • To improve realism in airframe utilization, routes, fleet mix/equipage • Re-routing to avoid weather and congestion