Air Chief Marshal is a military rank in the air forces of several countries, including Great Britain. It is a four star rank, equivalent in seniority to a General in the Army, or an Admiral in the Navy. Thailand, apparently, has two currently serving Air Chief Marshals: Air Chief Marshal Itthaporn Subhawong, the 21st commander-in-chief of the Royal Thai Air Force, who looks like this:
Foo Foo has, in fact, previously been in the news: in 2009, when a video leaked of a lavish birthday party the Prince threw for him, during which he required his wife, Her Royal Highness Princess Consort Srirasmi, to be topless throughout.
It is a crime in Thailand to make any criticism of the actions of the Royal Family. You can see why it would have to be.