Laboratory and captive flight experiments were performed using an instrumented Sparrow III missile to evaluate the relative merits of direct mechanical vibration and reverberant acoustic noise tests as techniques for simulating the Sparrow captive flight vibration environment. For the laboratory experiments, the mechanical vibration and acoustic noise excitations were applied in accordance with a common response-controlled test specification. The resulting missile vibration data were then standardized and compared with the vibration levels measured during captive flight to determine their similarity in terms of directional, spatial, and spectral distributions. The results indicate that the acoustic noise test simulated the captive flight vibration more accurately than did the mechanical vibration test. However, the accuracy of the simulation provided by the mechanical vibration excitation was not unacceptable for practical applications.