TagForecast(21)

This presentation, delivered on February 25, 2026, introduces the fundamentals of aviation forecasting as part of the airport planning process. It outlines how planners forecast passenger demand, aircraft operations, and automobile traffic, then identify physical, operational, and level-of-service constraints before developing and evaluating alternatives. The material emphasizes that while predicting future demand is inherently uncertain, structured forecasting is a critical first step in guiding airport infrastructure decisions.

A line graph showing CPI-adjusted airport capital spending in millions of 2025 dollars from 1998 through 2030 (with years 2025–2030 as forecasts), alongside a flat orange reference line representing average real spending from 1998–2024 at approximately $470 million. Spending peaked around 2002–2005 near $800 million, dropped to a low near $125 million in 2012, recovered to approximately $750 million by 2018–2019, and is forecast to peak near $975 million around 2027 before declining.

A line graph comparing three levy trajectories in millions of dollars from 1990 to 2026 (forecasted): the Maximum Allowable Levy (red), the Actual Levy (blue), and a hypothetical Levy Tied to Inflation beginning in 1990 (green dashed). The Actual Levy remained well below the Maximum Allowable throughout the period, with both projected to converge toward approximately $90–$120 million by 2026.

Slide 54 (page 56 of 95) from a Seattle-Tacoma International Airport (SEA) presentation compares 2026 forecast Cost per Enplanement (CPE) across five large-hub airports: DEN ($17.05), LAX ($37.60), ORD ($29.08), SEA ($21.10), and SFO ($29.03). Sources are cited as 2026 Budget documents or Preliminary Official Statements on bond issuance.

Bar chart published by Seattle-Tacoma International Airport (SEA) showing annual passenger counts from 2011 to 2024. The 2024 total of 52,640,716 passengers surpassed the previous record of 51,829,239 set in 2019, representing a 2% increase over the pre-pandemic peak.

Figure 4-1 from a Seattle-Tacoma International Airport planning document shows historical and forecast total aircraft operations (in thousands) from 2011 to 2038, broken down by passenger airlines, all-cargo airlines, and other operations. The forecast, sourced from LeighFisher (June 2022, updated August 2023), projects growth from 429,000 operations in 2023 to 567,000 by 2038.

A scatter plot comparing multiple historical and projected annual air carrier operations forecasts for Seattle-Tacoma International Airport, spanning approximately 1975–2010. The chart overlays actual operations data against projections from sources including 1997 FAA and ACC (Hockaday) projections, the 1992 Flight Plan Project Final EIS, the 1996 Master Plan Update FEIS, the 1987 PSCOG Draft EIS, and several earlier studies dating back to a 1976 Sea-Tac Communities Plan, illustrating how successive forecasts consistently overestimated growth relative to actual operations.