They are a fractional ownership program of business jets. They are owned by Bombadier and fly Lear 31a's, 45's, 60's, Challengers, and Global Expresses. They have crew bases in DAllas, South Florida, and the New York area
I don't think Flexjet is a charter airline. It is a fractional. Some companies and a few rich people buy shares of time. I'm not too sure how it all works but I think you pay an initial sum to join, then you are charged a monthly fee and an hourly rate when you use the aircraft. Customers are allowed to use the plane for a certain number of hours each year, the hours depend on how much you purchase. There is a big article about fractional companies in a recent issue of Flying magazine. It also sounds like this business is a popular alternative to airline flying for pilots.
Lax was correct in his detailing of Flexjet.They take advantage of part 91 rules claiming that the aircraft are owned by specefic owners. This allows the company to bypass FAR 135 requirements that charter companies must adhere to. They are in the process of changing all of this and the FAR's will have a special section to adress all of the "fractional" operations in the U.S. The pilots have schedules unlike corporate pilots but have no travel priveledges or jumpseat priveledges on the airlines. Some have tried to jumpseat but they cannot reciprocate so normally they are denied. It is a good alternative to flying for an airline now that airlines aren't hiring. You fly new jets to neat destinations and if you don't mind being the flight attendant and the bag carrier, it might be for you.