A Systems Approach to the Aeromedical Aircraft Routing Problem Using a Computer-Based Model

This research concerns transporting medical patients on specially- equipped aircraft from one medical facility to another, primarily to provide them treatment not available at the first facility. In addition to finding improved routing methods so that patients can be moved as directly and expeditiously as possible, we address other important issues by means of a systems approach, such as the limited numbers of aircraft and crews that restrict the ability of the system to provide direct or even same-day service. Of the world-wide DOD network, we examined only the continental US portion, and we were primarily concerned with its peacetime operation. The purpose of the thesis is to design and aeromedical planning system that will schedule weekly regional service, and produce daily routings. Historical patient movement data provides information that can be used in regional service planning. At the root of routing and sequencing is the combinatorially difficult problem of finding solutions that satisfy the ordering restriction that patients be picked up before they are delivered. Routing problems which require both pickup and delivery service are commonly called many-to-many, two-ended service problems. We present solution methods for both multiple depot and multiple aircraft many- to-many problems. (AW)