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wherein tail slap at the cavity wall is a definite possibility [Kulkamni and Pratap 1999]. Vehicle rotation has also been predicted [Kulkamni and Pratap 1999].

      The aforementioned design considerations and conditions have led to piecewise research in specific areas like cavitator designs [Stinebring et al. 2001], numerical prediction [Kunz et al. 2000], cavity thickness measurement using novel methods [Li et al. 2002a, 2002b, 2002c] etc. However, supercavitation itself has been studied for a long time. The use of supercavitation in high-speed marine propellers, hydrofoil boats, and low-head pumps/turbines sparked a renewed interest in the subject [Tulin 1961]. Added to this, supercavitation with respect to bodies of revolution have been under scrutiny in recent times especially with regard to underwater artillery [Tulin 1961]. As a result, associated topics such as water entry, dynamics, and control have been the subjects of theoretical and experimental studies [Tulin 1961].

      While supercavitation applied to underwater vehicles is of a great tactical merit, one of the principal tradeoffs is the stability and maneuverability of the vehicle. While the stability is dictated by the design of the vehicle and also by the dynamics of the cavity, the maneuverability depends on the prediction and control of the cavity shape and vehicle dynamics in the presence of fins. For the prediction and control of the cavity, there is a need to (a) measure the local cavity thickness, (b) understand the interfacial instabilities at the cavity wall and (c) employ a suitable control algorithm.  The measurement of cavity thickness has necessitated the need for innovative technology. Related research areas including algorithm development, sensor manufacturing and experimentation are in progress [Chandrasekharan et al. 2001la, 2001ib, 2002; Li et al. 2002a, 2002b, 2002c].