Experience gained from the American Airlines SABRE system control program

Abstract

Just over ten years ago, IBM and American Airlines undertook the development of a real-time airlines reservations system. At that time, there were several systems in use by the airlines to present “yes-no” information on seat availability and in some cases maintain seat inventory counts. None of these systems, however, performed the complete “back-room” job of filing records, sending communication messages, processing wait-lists, preparing boarding manifests, etc. Significant improvements in passenger service were expected if the many possible sources of error in these operations could be reduced. The effort included development of specialized pieces of equipment and of a control program to interface between the application programs and the hardware. This was at a time when operating systems were just beginning to come into use. This paper concentrates upon the control program architecture, setting forth the important lessons that were learned after the system became operational.