1. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Demand Generation for System-wide Simulation Glenn Foster MITRE CAASD January 27, 2010

2. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. 2 Background MITRE CAASD performs system-wide analyses to answer many questions Demand is a key input into system-wide analyses

3. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. 3 System-wide Modeling Question Which sectors will not be able to accommodate expected demand? How many scenario days are required and which days? How to handle airspace changing over time?

4. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Sample Size and Day Selection 44

5. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Number of Scenario Days Background Select a sample of days that can be used as input into system-wide analysis –Represent a range of selected metrics over the year of interest –Results from system-wide analysis can be used to characterize the performance over the year of interest Analysis first focused on determining number of days that are needed to achieve coverage of traffic at the sector level –Motivated by use of the system-wide analysis for identifying bottleneck en route sectors 5

6. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Coverage of Sector Traffic Analysis conducted on FY2006 sector traffic data –Daily sector counts were sorted into quartiles Random samples of various sizes (number of days) were chosen –Each day in the sample can be mapped to one of four quartiles for every sector –Coverage = The sample set contains at least one day mapped to each of the quartiles for all sectors + + + … = 6

7. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Evaluating Sample Sizes for Coverage of Sector Traffic 7

8. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Effect of Sample Size on Estimates of Average Daily Operational Delay 8 Each box-whiskers plot represents 200 random samples of n days from FY2006 ASPM Each sample is a different estimate of Average Daily Operational Delay Box = interquartile range the estimates Whiskers = Total range of the estimates Red = Average of the estimates Most of the improvement in the range of the estimates occurs as samples sizes increase up to ~ 30

9. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Creating a Sample Set with FY2008 Data - Extension of Approach to FY2008 Data and Other Metrics Sample of size 36 chosen (same number of days per month) Sector traffic counts only analyzed for FY2006 data –However, conclusion expected to hold for other years Look at coverage for other metrics –Airport delays from ASPM –Number of non-VMC hours per day per airport from ASPM –Center counts from OPSNET Generate 5000 samples of 36 days –3 days from each month in FY2008, including the 8 FAA sample days Select sample with the most even coverage across the quartiles of the available metrics 9

10. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. CAASD’s FY2008 Selected Scenario Days 10 CAASD produces a 36-day sample CAASD’s sample attempts to provide coverage over range of 1.Airport delays 2.Airport weather 3.Center traffic levels

11. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. CAASD’s FY2009 Selected Scenario Days 11 CAASD produces a 36-day sample CAASD’s sample attempts to provide coverage over range of 1.Airport delays 2.Airport weather 3.Center traffic levels

12. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Defining Airspace for Scenarios 12

13. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. 13 Choice of Airspace Adaptation FY2009FY2008FY2010 Demand Type 1: Base Year Base year airspace adaptations (56 day cycle) Adaptation #1 #2 #3 #4 #5 #6 #7 #8 = Selected base year day Approach: Match demand day with adaptation Approach: Recent adaptation and consistent routes FY2014FY2013FY2015 = Corresponding future year day Recent airspace adaptation (started Oct. 22, 2009) Demand Type 2: Future Year No Action FY2014FY2013FY2015 Demand Type 3: Future Year ActionApproach: Recent adaptation and consistent routes Plus Recent airspace adaptation (started Oct. 22, 2009) plus planned airspace changes (Chicago, Houston, Las Vegas, New York)

14. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Future Airspace and Routes Reroute Example April 10, 2008 – ZAU and C90 begin placing southbound departures onto five new routes (replacing existing three) Example –April 8 KORD..RBS..FAM..LIT.J180.SWB.DAS6.KIAH –April 17 KORD..BACEN..BLOKR..BEKKI..ROCKY..BRADL..SWB.DAS6.KIAH All C90 southbound departure flight plans for scenarios prior to April 10 are placed on new routes in the future scenarios RBS BACEN BLOKR BEKKI 14

15. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Altitude Restrictions Example 15 Actual Track data Trajectories with old altitude restriction Trajectories with modified altitude restriction Impact on ZLA sector 15 as a result of updating an altitude restriction applying to LAX arrivals Using old restriction Modified restriction 15

16. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Summary 16

17. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. 17 Summary MITRE CAASD generates demand for system- wide analyses Analysis was performed which resulted in defining samples of size 36 days Day selection was performed for FY2008 and FY2009 to provide the “best” coverage over chosen metrics Airspace adaptations are chosen to match scenarios –Future scenarios can include planned airspace and the corresponding route changes

18. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Backup Slides 18

19. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. FAA and CAASD’s FY2008 Selected Scenario Days 19 FAA selects a peak and off- peak day for each fiscal year quarter producing an 8-day sample CAASD has added 28 more days producing a 36-day sample CAASD’s sample attempts to provide coverage over range of 1.Airport delays 2.Airport weather 3.Center traffic levels = FAA Day

20. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Pre-Processing for Merging and Spacing Resource 20 In an earlier version of systemwideModeler, flights delayed due to airport arrival capacity took the delay at the last possible point – the “hurry up and wait” approach Implemented first phase of modeling improvement Current version now delays flights farther upstream Flights requiring airport arrival delay spread their delay over their “merge nodes” Pre-processing: In the demand generation process, the arrival flow merge nodes are identified from flight trajectories Airport MAS Merge Nodes

21. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. Pre-Processing for Departure Fix Resource 21 Departure sectors could be presented with too much demand due to a directional departure push over the same fix. Departing flights were not constrained per directional flow Implemented modeling improvement When necessary, the model delays flights due to departure fix congestion ORD Departure Fixes after April 10, 2008 Pre-processing: In the demand generation process, departure fixes are identified from flight trajectories

22. F066-B10-006 Public Release No.: 10-0256 © 2010 The MITRE Corporation. All rights reserved. 22 For Release to All FAA. This document has been approved for public release. Distribution is unlimited. This is the copyright work of The MITRE Corporation and was produced for the U.S. Government under Contract Number DTFA01-01-C-00001 and is subject to Federal Aviation Administration Acquisition Management System Clause 3.5-13, Rights in Data-General, Alt. III and Alt. IV (Oct. 1996). No other use other than that granted to the U.S. Government, or to those acting on behalf of the U.S. Government, under that Clause is authorized without the express written permission of The MITRE Corporation. For further information, please contact The MITRE Corporation, Contract Office, 7515 Colshire Drive, McLean, VA 22102, (703) 983-6000. The contents of this material reflect the views of the author and/or the Director of the Center for Advanced Aviation System Development, and do not necessarily reflect the views of the Federal Aviation Administration (FAA) or Department of Transportation (DOT). Neither the FAA nor the DOT makes any warranty or guarantee, or promise, expressed or implied, concerning the content or accuracy of the views expressed herein.  2009 The MITRE Corporation. As such, the Government retains a nonexclusive, royalty-free right to publish or reproduce this document, or to allow others to do so, for “Government Purposes Only”.