I have recently been communicating with CASA on an error in the current AIP. For those of you who are currently studying IREX there has been an error in AIP GEN 1.5 para 8.5.5.3. It currently says that a C129a GPS can be used to satisfy the requirements for an alternate based on the approaches available at the destination aerodrome. That is incorrect. A C129a GPS can never be used to avoid the alternate requirements imposed by navigation aids. Air Services has advised me that the reference to C129a GPS in that paragraph will be removed in the next print of the AIP. So, if you are sitting the CASA IREX exam shortly, be advised that a C129a GPS cannot be used to avoid the requirement for an alternate. This, of course, has always been the rule anyway.

Also, you cannot fly an RNAV[GNSS] approach with a C129a GPS unless another approach, based on a ground-based aid is also available at the aerodrome [AIP GEN 1.5 page 18 table centre panel].

Glad I did a quick search on topics before asking my question. I have just spent the last 20 minutes pulling my hair out flicking back and forth pages trying to figure out why this information seems so contradictory, I figured it had something to do with the way I was reading it as is normally the case with regs and rules. I can rest and go back to keep reading your IREX book now Bob