A modal survey test (MST) of the Titan 34D/IUS Pay-load Fairing (PLF) was conducted to characterize the PLF dynamic properties and to use the results to verify/modify the PLF dynamic model to be used in payload load studies. Two methods of modal testing were employed: 1) normal mode testing (NMT) using multi-point swept sine wave excitation, and 2) transfer function testing (TFT) using single point broad-band random excitation. Two models of the test article were used during the course of testing. A finite element (FE) math model of the cantilevered test structure was developed from which pretest modal characteristics including shell modes were determined. Additionally, a model was derived from that of the complete Boost Vehicle (BV) which included a less rigorous model of the PLF. This BV derived model was of centerline form and was to be subsequently used for generation of BV and Space Vehicle (SV) loads.
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