After 30 seconds rigerous search, I found that Walcott was licenced to fly a Westwind
http://web.nbaa.org/public/news/20051014atl.php
Wolcott is a commercial pilot with multiengine and instrument ratings and reportedly is licensed to fly a Westwind corporate jet. But he's not rated to fly a Citation, a plane that usually requires two pilots.
I think
Empty Cruise hit the nail on the head.
Chips