Please answer a question about the following article about Saint Helena:

Saint Helena is one of the most remote islands in the world, has one commercial airport under construction, and travel to the island is by ship only. A large military airfield is located on Ascension Island, with two Friday flights to RAF Brize Norton, England (as from September 2010). These RAF flights offer a limited number of seats to civilians.

What kind of flights are offered to limited civilians?
RAF flights