Apologies, my phrasing above was rather convoluted. In very simple English:
In Australia:
A domestic airline can be 100% foreign owned
An international airline must be majority Australian owned
Virgin Australia splits its assets into VA (domestic) (where it has all its assets) and VA International Holdings - which is basically a $1 paper company that is majority Australian owned - but bearing in mind this paper company has no assets
VA (domestic) enters into a loan agreement with the paper company, where VA "injects" capital needed into VAIH through a "loan agreement"
VA (domestic) enters into a management agreement with VAIH, whereby management of the $1 company is done by VA (domestic)
In effect - VA (domestic) funds and controls VAIH. The letter of the law is respected, with VAIH being majority owned by Australians - all $1 of it.
VA (domestic) is 70% owned by SQ, EY, NZ, 11% by Virgin Group and the rest of it is free float. It is majority foreign owned, arguably does not respect the spirit of the law, but remains perfectly legal
In Singapore:
A carrier with a Singapore AOC must be at least 51% owned by Singaporeans
Jetstar Asia is on paper a JV company called Newstar - 51% owned by Westbrook (which in turn is owned by Denis Choo) and 49% owned by Qantas
Qantas "loans" Westbrook the requisite amount of money to "buy" 49% of Newstar
Qantas signs a management agreement with Newstar to ensure that they have the right to control the company and its cash
On paper, Jetstar Asia is 51% owned by Singaporeans and has a board made up of a majority of Singapore nationals
In practice, Jetstar Asia is 100% funded and controlled by Qantas
This structure also does not respect the supposed spirit of the law, but remains perfectly legal and blessed by the Singapore government
Unlike Hong Kong, Dixon worked out the structure and got it blessed by the Singapore government in 2003, and even got them in as initial investors.
Such structures are used all over the world where there are restrictions in foreign direct investment in certain industries - such as retail, mining etc. It is easy to dictate that you can't own a direct stake in a certain company. However it is almost impossible to regulate that Company X is barred from lending Company Y money, and enter into a management and franchise agreement with Company Y.