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Reliable aircraft components capable of operating in the extreme conditions of hypersonic flight have wide-ranging applications in the development of future commercial and defense air vehicles. A major obstacle to this objective is that the thin skin panels that compose aircraft structures may warp into states with multiple static equilibria. These panels may then exhibit snap-through, or high-amplitude oscillations between static equilibria, in consequence to the mechanical, thermal, and acoustical loads experienced by aircraft traveling at hypersonic speeds. This “skin buckling” phenomenon permanently deforms airframe panels, leads to decreased flight performance characteristics, increases wear on structural components, decreases structure life, and may result in catastrophic failure. While the steady-state dynamics of single degree-of-freedom bistable structures have been well characterized, it is unclear how to generalize this knowledge to a complex multistable structure, such as a post-buckled aircraft panel, having multiple degrees-of-freedom. To gain a fundamental understanding of multistable structures operating in extreme environments, this research experimentally investigates an archetypal, built-up multistable structure that consists of coupled, bistable beams. Experimental parametric studies are conducted on multiple configurations of this archetypal structure to uncover relationships among excitation features and mechanical impedance. The results of this research are used to articulate a new method of experimental investigation of multistable structures that may be used to forecast dynamic regime changes that may manifest in built-up aerostructures operated in the extreme conditions of hypersonic flight.