Meanwhile on another thread, the US "WAAS of the future" might eclipse the whole thing.
[URL=www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/mobileAll/WAASoftheFuture.pdf[/URL]
Read this briefing from the FAA and ask yourself when the last time was that you read something this cogent or this far sighted from CASA