"Sam Spade" wrote in message
...
Stan Prevost wrote:
"Sam Spade" wrote in message
...



What's to identify? If it is not an IAF, and not the FAF, and is on an
intermediate segment, it is an IF. Why does it need to be "identified"?

Because sometimes there is a stepdown fix, or two, in the initial segment,
and sometimes there is a stepdown fix, or two, in the intermediate
segment. In that event you do not know which fix is the intermediate fix
(well, we're really speaking of waypoints since this is an RNAV-only
procedure).


OK, that helps. Although, as Roy said, it doesn't seem to matter much, the
distinction has become blurred. The controller is supposed to issue an
altitude restriction for the vector that is consistent with the MVA/MIA,
thus insuring obstacle clearance, so it is not obvious why IAF vs IF vs
stepdown fix really matters. But, the rule ought to be clear.

I had thought that all the fixes between an IAF (or the beginning of the
procedure) and the FAF are IFs (disregarding fix vs waypoint). Apparently
that is not true, given stepdown fixes on the initial segment. Don't think
I have seen one of those, but they seem to be allowed by TERPS. But I also
thought that all fixes on the intermediate segment were IFs. But that does
not seem to meet the definition of IF in the P/CG.

The altitude issue is a big problem with this business of vectoring to the
IF on RNAV approaches. If the IF altitude is not at or above MVA/MIA, the
approach may not be flyable with vectors to IF. 7110.65 does not give
guidance to controllers on that issue, that I can find.