This is what happens when nobody asks aviation what augmentation would do.
202.2.9 Aviation
Global Navigational Satellite Systems (GNSS) are increasingly being used in all sectors of the aviation industry as an aid to navigation. Regulatory authorities have acknowledged this trend and incorporated GNSS in regulatory policy and procedures.
Aircraft navigation does not generally require high position accuracy for lateral guidance. The accuracy available from stand-alone GNSS when operating properly is sufficient for most situations.
Integrity is more important with around 4 nautical miles required over ocean, 2 nautical miles over land and 0.3 nautical miles required for non-precision approaches. Precision approaches require integrity of around 40 metres.
Higher levels of vertical positional accuracy are required for precision approaches and landings.
There are two navigation technologies that can be used in precision approaches • Instrument Landing Systems (ILS) that broadcast a flight path from radio beacons on the airstrip that are received by an ILS receiver in the cockpit • Ground Based Augmentation Systems (GBAS) that provide augmented GNSS at airports.
GBAS could deliver savings in fuel costs if installed at all major Australian airports. However, other landing systems, including ILS, deliver similar savings. Accordingly little net benefit for airlines in lower fuel costs could be claimed for GBAS.
GBAS would deliver cost savings for infrastructure at airports compared to ILS. However ILS is to be maintained for the time being as not all aircraft are GBAS equipped.
Savings in capital costs to replace terrestrial navigation aids of around $119 spread are possible with RAIMS1 capable GNSS.
Space Based Augmentation Systems (SBAS) provide augmented GNSS over a wide area. However, the net benefits of an SBAS to the aviation sector alone do not appear to be sufficient to justify the cost.
One guesses the authors of this article only talked to two people at AirNoServices and Lockheed Martin