I think City Air Links were based in the Isle of Man.  This was taken in the early 1980's and was parked near to the old London gate at BHX.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/130275500@N02">G B_NZ</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/130275500@N02/23711072099/">City Air Links PA-23 Aztec G-CALL at BHX</a>