International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A typical telemetry system for aircraft flight-testing transmits one or several data streams to the ground for real-time display and analysis, and also records the same stream onboard for later playback. During test operations, only a fraction of the available data is used at any given time for real-time display or analysis. More efficient use of the RF channel could be realized if only the data needed for the current test point is transmitted, rather than the entirety of the data. Intelligent selection of a subset of the data stream can provide large reductions in the required telemetry downlink bandwidth. As one of the Advanced Range Telemetry (ARTM) On-Board Data Management (OBDM) initiatives, a prototype on-board data selection subsystem is being developed and demonstrated. The demonstration utilizes COTS telemetry workstations to the maximum extent possible and includes “plug-in” data requestor, selection, and server components to implement the added DML functionality. A significant objective of the OBDM/DML project will be to validate RF channel models to help minimize the amount of flight-testing necessary to validate the DML concept. This paper will discuss the OBDM/DML architecture, integration of several custom components with the COTS portions of the ARTM “test bench”, and the current status of the OBDM/DML development and test program.