Originally Posted by
jackal
Ah, interesting!
From my reading of your posts, it seems that Capstone seems to take some of the features of RNP (ground proximity warning, etc.) and build on them but without the strict reliability requirements RNP includes (I seem to recall reading something about RNP 0.3--which, as you inferred, would require a high degree of location certainty within 0.3 NM).
Does Capstone allow for precision approaches and reduced minimums? Or is it strictly an avionics package that assists with situational awareness and allows for IFR separation in an en-route environment where there is no radar coverage (i.e. below the MEAs, which, IIRC, are instituted to ensure adequate radar coverage), and approaches are still in effect GPS non-precision approaches?
If that's the case, then it appears they're perhaps targeted at different types of flying. Still, are there aspects of Capstone that would be useful for the kind of flying AS does? Does AS have any plans to outfit their aircraft with Capstone avionics or systems providing equivalent functionality?
No Capstone does not provide for reduced approach min or actually approaches at all. It is limited to one GPS so they can perform a public GPS approach but not RNP. Remember RNP also takes pilot certification as well as approach certification. So not just any pilot may perform an RNP approach like only certified pilots may do CatIII approaches. Capstone is designed really for enroute ops and enhanced situational awareness plus the ability for ATC to provide basic IFR service. Normally they would transition to the good old VOR or ILS approach if needed. RNP is much more accurate using multiple GPS and INS systems to very accurately determine position.
The only interface between the two for Alaska is that because they send their position via data link, Capstone aircraft will have TCAS so we will be able to see them. TCAS is a aircraft to aircraft collision avoidance system. Alaska jets have it but most aircraft flying in non radar areas of Alaska don't install a transponder. Without the transponder we can't see them on TCAS. Since Capstone equipped aircraft will now have this equipment even in non radar areas Alaska jets will be able to see the other aircraft now just like in the lower 48.