Building the Timetable from Bottom-Up Demand: A Micro-Econometric Approach

The aviation community has a rich collection of tools that simulate the operational flows of the National Airspace System (NAS). In nearly all cases, modeled operational flows of aircraft in the NAS begin with a schedule generated outside of the model. In the past, the schedule has been derived by translating the Federal Aviation Administration's (FAA's) Terminal Area Forecast (TAF) into flights. The downside to this, however, is that NAS operations are made up of specific airport-to-airport flows, which may be different from terminal area growth attributable to those airports. The challenge is to move from a generic traffic count at a specific terminal to a schedule of flights that includes a "when" and a "where" dimension. Modeled NAS operational performance is highly dependent on the characteristics of the forecasted operations; hence it is critical that the traffic schedule be created correctly. The top-down approach based on TAF projections achieves its goal of replicating the intended volume of flights at each airport, but it does not necessarily achieve the desired operational-level integrity. In other words, the existing method is not capable of forecasting route-specific growth in operational flows. At the MITRE Corporation's Center for Advanced Aviation System Development (CAASD), we are building a framework which attempts to fill in the gaps mentioned above using a bottom-up, demand-driven micro-econometric approach. Our ultimate goal is to produce a schedule of flights that is linked with origin and destination (O&D) operations via passenger route choice. It should thus be in sync with the Official Airline Guide (OAG), but not driven by it. Our method is comprised of six basic steps, beginning with estimation and forecasts of traveler demand between O&D city pairs, and culminating with the creation of a forecasted schedule that incorporates all major aspects of passenger demand.