Originally Posted by Denti
A GLS approach in automatics can only be flown with the approach mode currently and the approach mode (same as VORLOC) is only able to track straight in approaches, not curved ones. Which explains why both RNP (AR) and curved GLS approaches are not possible in approach mode. Of course one could fly a curved approach manually following the normal needles. RNP (AR) can be flown in LNAV/VNAV which can follow curved approach paths, but isn't a precision approach mode.
Not sure what you mean by this, curved RNP approaches are possible on the A320, jetBlue and Air New Zealand are some of the early operators that were approved for them. On the A320/30/40/80 GLS is a customer option, it will be standard fit on the A350 like the 787 and 747-8.
www.caa.govt.nz/pbn/AR_Mtg/airnz.pdf
http://www.airbus.com/fileadmin/medi...-GEN-SEQ02.pdf