Isint the purpose of any franchise to take a successfull buisness model which requires (and allows for) little to no entreprunerial input, with a view that 'running' a buisness in the confines of a small box one cannot fail (McDonalds the classic example).
The product of the franchise is really not important but the model surrounding the buisness is.
Now correct me if im wrong but the Jetstar buisness model has proven to be somewhat of a failure. Franchising may work for the likes of South West or Easyjet but from what little I admittedly know about it, the Jetstar model has too many faults.