This is not the first time these approaches at KAPC have been discussed here. Recently, I was planning some practice approaches and and considered the RNAV 36L at Napa County (KAPC). Actually there's three of them, X/Y/Z. It took quite some time to go through these plates to figure out what all the differences are. This might be a good training puzzle for students. Have any CFII's used them before? Here's just one question you could dream up: Say you want to fly one of these approaches LNAV with an older non-WAAS GPS. Comparing RNAV X and Z, the MDA for Z is 20 feet higher (600 vs 580) but Z requires a better climb gradient on missed (480 vs 410). Why? I think I know the answer. Or maybe I've got it wrong. What do others think?