Exactly! Why wouldn't you do one in flight? Finding out on a 7nm final in IMC is prob not "best practice".
That's exactly what I am saying...
Form 645, Item 53, RNAV (GNSS) RAIM availability checked.
This is not just an ATO personal quirk, and notice how all of these requirements are chronologically ordered for each approach type? Notice how item 53 comes before the entry and holding pattern?
Same thing for DGA. RAIM availability checked
again cometh before descent.
My understanding is RAIM warnings are inhibited after the FAF and the GPS will provide a DR nav solution for 5 minutes after the loss of RAIM after passing the FAF, meaning an approach can be completed and if necessary missed approach can be carried out in DR mode.
So you want to be tooling around at less than 800' AGL in IMC in DR mode when there was an indication RAIM wasn't going to be there? Really?
So, an out of date RAIM prediction says no, a more current one says yes, and there has not been a RAIM failure or warning, but you're going to turn around and go home if thats the only approach?
As before, you want to take that risk?