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The G34.3+0.2 radio continuum source (G34.3+0.2 component C) is an ultracompact HII region that exhibits a cometary-like morphology. Many models have been offered to explain the distinctive cometary shape of both the G34.3+0.2 C HII region and other similar ultracompact HII regions. The most detailed models are the champagne flow model (Yorke et al. 1983, A\&A, 127, 313) and the moving star bow shock model (Van Buren et al. 1990, ApJ, 353, 570). These models predict specific radio continuum morphologies and radio recombination line velocity signatures that can be compared to observations.
New, deep radio continuum images and radio recombination line data are presented which demonstrate that neither the champagne flow model nor the moving star bow shock model adequately explain G34.3+0.2 component C. We present a qualitative model for the G34.3+0.2 cometary HII region that can explain most of the current observations.