Porbably on the Houston run.  I was waiting for my USAir 737 to PHL.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/130275500@N02">G B_NZ</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/130275500@N02/23390397335/">Southwest 737-300 N332SW at DFW</a>