The Digital Voice Response System (DVRS) is a totally integrated system which was developed in the Flight Simulation Subdivision of the McDonnell Aircraft Company (MCAIR), a division of McDonnell Douglas Corporation (MDC) at St. Louis, Missouri. The system was designed to simulate Automatic Terminal Information Services (ATIS) broadcasts and Ground-Controlled Approach (GCA) instructions for real-time man-in-the-loop flight simulators and trainers. Consisting of a single printed circuit card integrated into a commercially available personal computer, the DVRS achieves a high degree of realism by digitally recording, during nonreal-time, the voice of an experienced controller or ATIS broadcast (along with associated radio and environmental noise) as a series of messages and then playing back the appropriate message or messages, as selected by the simulation host computer, during real time. In addition to voices, other sounds typically heard in the pilot's environment can also be reproduced by the DVRS. Missile launch, gun fire, engine noise, and aural tones associated with crewstation cautions and warnings are common examples of aircraft sounds.