International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper discusses Global Positioning System (GPS) Range Applications Joint Program Office (RAJPO) efforts to foster interoperability between airborne instrumentation, virtual simulators, and constructive simulations using Distributed Interactive Simulation (DIS). In the past, the testing and training communities developed separate airborne instrumentation systems primarily because available technology couldn't encompass both communities' requirements. As budgets get smaller, as requirements merge, and as technology advances, the separate systems can be used interoperably and possibly merged to meet common requirements. Using DIS to bridge the gap between the RAJPO test instrumentation system and the Air Combat Maneuvering Instrumentation (ACMI) training systems provides a defacto system-level interoperable interface while giving both communities the added benefits of interaction with the modeling and simulation world. The RAJPO leads the test community in using DIS. RAJPO instrumentation has already supported training exercises such as Roving Sands 95, Warfighter 95, and Combat Synthetic Test, Training, and Assessment Range (STTAR) and major tests such as the Joint Advanced Distributed Simulation (JADS) Joint Test and Evaluation (JT&E) program. Future efforts may include support of Warrior Flag 97 and upgrading the Nellis No-Drop Bomb Scoring Ranges. These exercises, combining the use of DIS and RAJPO instrumentation to date, demonstrate how a single airborne system can be used successfully to support both test and training requirements. The Air Combat Training System (ACTS) Program plans to build interoperability through DIS into existing and future ACMI systems. The RAJPO is committed to fostering interoperable airborne instrumentation systems as well as interfaces to virtual and constructive systems in the modeling and simulation world. This interoperability will provide a highly realistic combat training and test synthetic environment enhancing the military's ability to train its warfighters and test its advanced weapon systems.