Storm-Induced Arrival Deviations into Departure Airspace and Their Relationship to Weather Impact Mitigation Needs and Performance

Across much of the National Airspace System (NAS), convection impacts critical arrival and departure airspace resources indiscriminately, causing significant disruptions and travel delays. Management of weather-impacted arrival and departure traffic, however, is not indiscriminate and typically not balanced: in the interest of safety, inbound, airborne arrival traffic is considered a higher priority compared to outbound, waiting-to-takeoff departure traffic. As such, arrival traffic maneuver as needed through en route to terminal transition airspace to avoid adverse weather – often utilizing portions of nearby, unimpacted departure airspace to safely accomplish these deviations. Unfortunately, these Arrival Deviations into unimpacted Departure Airspace (ADDA) can significantly contribute to airport departure operation disruptions. ADDAs affecting high-demand, capacity-constrained airspace and airports can result in unused departure airspace capacity and increased departure delays, longer airport departure taxi queues (and associated increases in fuel burn and emissions), increased airport surface congestion and complexity, and, at times, excessive taxi times and airport gridlock.

This paper presents results assessing the frequency and characteristics of ADDAs for five key Terminal Area Control (TRACON) regions (N90: EWR, LGA, JFK airports; C90: ORD, MDW airports; A80: ATL airport; D10: DFW airport; PCT: BWI, DCA, IAD airports) during two years of operations (2011, 2014). Objectively-identified events and trends in ADDA occurrences are used to frame larger discussions on the evolution of Air Traffic Management (ATM) objectives, decision support, and Traffic Management Initiatives (TMI) seeking to balance convective weather impact mitigation with dynamic, agile airspace capacity utilization. In this context, the implications for weather forecast requirements in seeking to minimize costly ADDA events and to support a more balanced (e.g., arrivals vs. departures; airborne vs. ground) air traffic operation are explored.