• 2026-04-28

    Washington State Unconstrained Forecast: Draft Presentation

    This draft report, prepared by the Commercial Aviation Work Group and consulting firm Steer, presents an unconstrained air travel demand forecast for Washington State's 17 busiest commercial airports, with Seattle-Tacoma International (SEA) accounting for the vast majority of the state's approximately 29.8 million enplaned passengers in 2025. The forecast combines a short-term bottom-up model based on airline schedules with a long-term top-down model driven by macroeconomic factors such as GDP, population, and airfares, ultimately producing airport-level traffic projections. While focused on statewide aviation demand planning, the findings have direct relevance to Sea-Tac noise policy discussions given SEA's dominant share of regional air traffic.