Crack on with that FOI request champ, make sure you actually read what it says though, since you seem incapable of doing so within this thread, where more than sufficient answers have been given to your query, in between the banter, not to mention disgust at your belligerent and supercilious attitude.
Since you seem to need it dumbing down further; 'Flying Pay' is a name, the pay is for the type of work, rather than the quantity thereof. It is (once more) for recruitment and retention. As a purported businessman, one would have expected you to understand the principle of supply and demand.