Hey,

Just wondering if anyone knows the reference for the requirement to conduct a raim check on the gnss receiver before starting an rnav, or if this is even actually a requirement.

Thanks

Hi KF,
This is testing the memory a bit but I don't think there is a pre approach requirement, just have to get a forecast for RAIM outages during pre flight planning. I know AIP ENR 1.10 mentions GNSS prediction for oceanic and remote area flights but not approaches.

Hope this helps.
Mister W.

I studied this several years back for initial issue with wings EN,
my notes say...
RAIM
IN CTA you MUST notify centre if it is out for 5 mins AIP ENR 1.1.19.10.2

MY NPA laminated sheet I made 5 years back says
a pilot may not conduct an NPA unless amongst other things
RAIM is checked for destination.
and if RAIM is checked at 2 miles green to go to approach.
I did practice for a gnSS GDA the other day and my instructor got me to do a raim check on ground thirty miles away from destination and we didn't do another for whole flight based on the fact my GNSS box would flag a RAIM alarm.

Does this help/

I studied this several years back for initial issue with wings EN,
my notes say...
RAIM
IN CTA you MUST notify centre if it is out for 5 mins AIP ENR 1.1.19.10.2

MY NPA laminated sheet I made 5 years back says
a pilot may not conduct an NPA unless amongst other things
RAIM is checked for destination.
and if RAIM is checked at 2 miles green to go to approach.
I did practice for a gnSS GDA the other day and my instructor got me to do a raim check on ground thirty miles away from destination and we didn't do another for whole flight based on the fact my GNSS box would flag a RAIM alarm.

Does this help?

I never ever held a DME arrival as I never owned a DME equipped plane (true story)
now with radio aids being switched off and my instructor told me from next year there will be no radio aid theory taught? for IREX the question I need to ask is???

IS A GNSS ARRIVAL AN NPA?

CAAP 178-1(2) 2012 page 13 says

YES IT IS
A GNSS ARRIVAL is a unique procedure to Australia that provides an NPA to the Circling Minima.
A GNSS ARRIVAL is designed using the same criteria as used in conventional NPA design.

So Q???
Although I have GNSS NPA: GNSS NAV: IAL VOR

I don't have GNSS ARRIVAL or GDA as they now call it.
So Q why not?
Why do I have to go and fly and demonstrate a GNSS ARRIVAL for another FPA?
which is after all like an NPA which is one leg 1/360th of a GNSS ARR???

Maybe its because the NAV tolerances designed in it are using the ground based RADIO Aids,
you cannot use the GNSS for keeping your track.
something about the splay angles
CAAP 178-1-2-14-7.5.1
It is classified as TERMINAL APPROACH
and yes you do have to do a RAIM check b4.
2 cents

I think It is a requirement to check RAIM before relying on your GNSS device for an approach. During my flight training it is a fail if you do not check RAIM notams and then check RAIMS in your GPS before conducting an approach.
It's also good practice...