In an exclusive story Thursday, Texas Watchdog will shed more light on the abrupt retirement last month of the head of the Houston Airport System.

The story will show:

The amount of foreign travel that former Houston Airport System chief Richard Vacar undertook on behalf of a city-approved nonprofit dedicated to helping build and run airports in other countries. For example, Vacar made more than half a dozen trips to Quito, Ecuador, and half a dozen more to San Juan, Costa Rica -- two locations where the Houston Airport System was building and running airport operations. Vacar and other top airport officials took numerous other trips around the globe, raising questions about how closely he was overseeing the airport system in Houston.

That Houston Mayor Bill White knew about the nonprofit's overseas projects since at least January 2008, according to records obtained by Texas Watchdog. White had instructed the airport system then to provide quarterly profit-and-loss statements from the nonprofit's international work. White has said that he had increasing concerns in the weeks leading up to Vacar's departure about the extent to which Houston Airport System employees worked for the nonprofit.

And while it appears most of Vacar's travel was covered by the nonprofit, he took at least one trip to boost the nonprofit's business on the taxpayer dime. Taxpayers appeared to have shelled out $13,000 so Vacar could "explore opportunities for airport operations ... in Libya," records show. The tab was OK'd by Houston chief administrative officer Anthony W. Hall Jr. on March 13 of this year.

Come back here before noon Thursday to check out the story.