Oracle 1
My question is can newer more advanced and cheaper technology such as a GPS approach be validated for smaller airports that is transferable, eg aircraft based rather than physically based at the strip and how far away is it from being viable
The short answer is yes, but only if there is a WAAS like system in place. If there is, in an emergency, modern equipment can be programmed to set up a pseudo ILS like pathway to any runway, even one with no ILS.
Needless to say, we don't have a WAAS type system available in Australia, even though the Japanese WAAS like system (called MSAS) already covers Australia and we could use the Japanese Satellite system with a small investment.