This paper presents the development of a simulation test bed for a command, control, computer, communication, intelligence, surveillance and reconnaissance (C4ISR) system. The test bed features coordination of a rotorcraft unmanned aerial vehicle (RUAV) and multiple unmanned ground vehicles (UGVs) by integrating a high-fidelity rotorcraft model with actual ground-based robots that emulate UGVs. The RUAV component of the test bed is realized on a networked computer simulation, whereas networked robotics hardware is employed for the UGV representation. The RUAV dynamics run a high-fidelity nonlinear simulation model of a UH-60A Black Hawk helicopter. To emulate the dynamics of the UGVs, several networked Segway robots are employed. The proposed C4ISR system undertakes the task of mission management from the top level discrete-event supervision (DES) to the bottom level continuous-time regulation.