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The ATSL developed the following computer models over the years for various sponsors and research projects. These models can now be used for new and existing projects. Please contact the ATSL if you have specific interests in running analysis with these models.

Runway Exit Design Interactive Model (REDIM)

REDIM is a computer model developed to locate and design high-speed runway exits at airports. The model uses kinematic equations to characterize the aircraft landing dynamics and a polynomial-time dynamic programming algorithm to find the optimal locations of the high-speed exits. The objective of the optimization algorithm is to minimize the weighted average runway occupancy time (ROT) of an aircraft mix selected by the user. A database of aircraft characteristics for four Approach Aircraft Categories (AAC) has been included in the model to facilitate its use in a large variety of airport environments and conditions. The database file relieves the user's data-input burden, specially when the aircraft mix consists of many different types of aircraft. The program is developed to be used as a design and a planning instrument by engineers. Hence, considerable effort has been devoted to user interface such as menu system, interactive data editing, and graphical and tabular outputs.

Airspace Occupancy Model (AOM)

AOM is a computer model developed to estimate module and sector occupancies and constitutes the input to the Aircraft Encounter Model (AEM). The model takes flight plans or flight tracks, converts them into mathematical terms, scrutinizes the flight trajectory over a defined region of airspace to determine sector crossings and occupancies over time. The model provides graphical outputs of sector occupancies and generates data structures used to analyze pairwise aircraft conflicts.

Airspace Encounter Model (AEM)

AOM is a computer model developed to estimate module and sector occupancies and constitutes the input to the Aircraft Encounter Model (AEM). The model takes flight plans or flight tracks, converts them into mathematical terms, scrutinizes the flight trajectory over a defined region of airspace to determine sector crossings and occupancies over time. The model provides graphical outputs of sector occupancies and generates data structures used to analyze pairwise aircraft conflicts.

Transportation Systems Analysis Model (TSAM)

TSAM is a nationwide transportation planning model to forecast intercity travel behavior in the United States. It can be used to analyze the impact of transportation policy changes and the introduction of new modes of transportation to the existing transportation system. Mode specific metrics such as travel cost, travel time and generated revenue can be extracted and analyzed to measure the effects of such changes. Today it can forecast the automobile, commercial airline, air taxi and rail demand up to the year 2030 between all the counties in the United States. The commercial airline and air taxi demand is also reported at the airport level and at the station level for rail. Finally, the impacts on the National Airspace System can also be assessed with TSAM by using its output in conjunction with air traffic simulation software to model the commercial airline and air taxi traffic in the future.