1. Practical Applications of Probability in Aviation Decision Making Haig Iskenderian 22 October 2014

2. 2014 FPAW 2 Iskenderian Portfolio of TFM Decisions Ground Delay Programs Ground Stops Arrival & Departure Fix Metering Planning Horizon (Scale & Hours) 0 National 9+36 RegionalLocal Playbook Reroutes Airspace Flow Programs

3. 2014 FPAW 3 Iskenderian Sample Strategic TFM Decisions Sample Strategic Forecast ToolsStrategic Decisions TFM decisions require high-fidelity forecasts of storm structure and characteristics Throttle traffic flow? Strategic reroutes? Reduce airport arrivals? Manage tactically? LAMP (Probabilistic) CoSPA (Deterministic)

4. 2014 FPAW 4 Iskenderian Approaches to Probabilistic Forecasts for Aviation Model Ensemble Historical Data Translate to decision Translate to probability Probability of Impact Low Impact Medium Impact High Impact Take Action Take Action Model Ensemble Historical Data ? Medium Impact High Impact Low Impact Ensemble Airspace Classification NoYes Don’t Know 50% 100% 0% Thunderstorm Probability AFP!

5. 2014 FPAW 5 Iskenderian Decision-based Uncertainty Define ResourcesDefine DecisionsProvide Uncertainty 0.5 hr1 hr1.5 hr2 hr2.5 hr3 hr3.5 hr4 hr N E S W Terminal Gate Availability NY Metro FCA NY Metro Gates Time Blockage Low Impact Medium Impact High Impact Enroute Terminal 8 hr Time Blockage Low Impact Medium Impact High Impact 0 hr 1 hr2 hr3 hr4 hr5 hr6 hr7 hr8 hr FCAOB1 FCABW1 FCAA01 FCA Airspace Availability FCAOB1 Low Impact Medium Impact High Impact FCAOB1 West Gates 4 hr0 hr Most Likely Availability & Range

6. 2014 FPAW 6 Iskenderian Blockage forecast and uncertainty based on: –Model to translate storm intensity and height to blockage –Time-lagged ensemble of CoSPA forecasts –Historical forecast performance given scale, orientation, intensity of weather –Location, issue time, valid time FCA Blockage and Uncertainty Forecast Issued 12 UTC 13:0014:0016:0015:0017:0018:0019:0020:00 High Forecast Uncertainty FCA Blockage 0% 40% 60% 80% 100% 20% Time (UTC) Low Impact Medium Impact High Impact Most likely blockage Possible range of blockage TMI ? “Best Case” Scenario “Worst Case” Scenario Ensemble of CoSPA Forecasts Valid 8 Hours in the Future (20Z)

7. 2014 FPAW 7 Iskenderian FCA Blockage and Uncertainty Forecast Issued 12 UTC Forecast Issued 15 UTC 13:0014:0016:0015:0017:0018:0019:0020:0016:0017:0019:0018:0020:0021:0022:0023:00 Low Forecast Uncertainty FCA Blockage 0% 40% 60% 80% 100% 20% FCA Blockage 0% 40% 60% 80% 100% 20% Time (UTC ) Low Impact Medium Impact High Impact Regular forecast updates needed to revisit decisions TMI ! Low Impact Medium Impact High Impact Time (UTC) Low Impact Medium Impact High Impact Observed blockage TMI ? Ensemble of CoSPA Forecasts Valid 5 Hours in the Future (20Z) Ensemble of CoSPA Forecasts Valid 8 Hours in the Future (20Z) High Forecast Uncertainty

8. 2014 FPAW 8 Iskenderian Forecast Event Start, Duration and Recovery Event Start FCA Blockage 0% 40% 60% 80% 100% 20% Event start Forecast Issued 15 UTC Time (UTC) Low Impact Medium Impact High Impact 16:0017:0019:0018:0020:0021:0022:0023:00 Event recovery Time (UTC) 23:0000:0002:0001:0003:0004:0005:0006:00 FCA Blockage 0% 40% 60% 80% 100% 20% Forecast Issued 22 UTC Ongoing Event Ongoing event Event Recovery

9. 2014 FPAW 9 Iskenderian Traffic Flow Management decisions encompass a portfolio of time and space scales in the NAS Probabilistic forecasts cast in TFM decision space could yield considerable operational benefit for strategic planning –Convert high-fidelity weather forecasts to aviation impact, then provide probability of impact –Provide event start, severity, and duration –Focus here on enroute airspace, but similar approach could be used for other airspace and time horizons Probabilistic forecasts need to update regularly so that TFM decisions can be revisited and revised Summary

10. 2014 FPAW 10 Iskenderian Map FCA blockage to flow rate Consider uncertainty for broader portfolio of decisions Incorporate other models in decision-based uncertainty (SREF, LAMP) Future Work