A distributed simulation experiment conducted using a High Level Architecture (HLA) federation object model and the Runtime Infrastructure (RTI) was performed by the Johns Hopkins University Applied Physics Laboratory (JHU/APL). To explore the utility of the HLA and RTI for representative military problems, the experiment simulated two power projection scenarios. For the first scenario, a simulated Tomahawk guided missile with intelligent anti-armor submunitions was launched against an armor column. In the second scenario, an advanced hypersonic missile was simulated as an anti-TEL (Transporter Erector-Launcher) weapon following a Scud launch. In both scenarios, two Unmanned Aerial Vehicles (UAVs) were used to detect and track targets, one with Moving Target Indicator (MTI) radar and one with Electro-Optical and Infra-Red (EO/IR) sensors. This allowed initial targeting and, in the first scenario, dynamic re-targeting of the Tomahawk missile. The EO/IR UAV payload operator station (based on the Predator UAV) was simulated with virtual imagery in real-time and a user interface which allowed an operator to select and control the sensors dynamically. A Virtual Strike Battle Station (VSBS) with a virtual reality user interface was used to simulate the command and control center. Lastly, the Tactical Event System (TES) was simulated to provide detection information of Scud launch events in the second scenario.

This paper describes the HLA implementation and lessons learned for using the HLA for realtime human-in-the-loop simulations. Specific problem areas are described and a suggested "road-map" for building HLA/RTI simulations is presented.