wrote:
We are procedurally in violent agreement. Nonetheless, the G/S is not
primary prior to the PFAF, any minimum altitude constraints
notwithstanding. That is the legalese of Part 97. I am just the messenger.


We're agreed that at SCK following the glide slope down from the 2000
foot vector altitude is the best procedure. We're also agreed that the
G/S is not primary outside the PFAF. Instead, one must abide by the
published altitudes - in this case we must remain above 1800 until this
PFAF. At SCK, this is logically guaranteed by our "best procedure".

However, I detect that your position is still that some sufficiently
zealous FAA inspector could violate me for using the G/S to descend to
1800. (otherwise how could the new instructor be "technically
correct"?). I disagree. If that is your position, please cite which
verse of Part 97 that this zealous inspector could attempt to violate
me on? Which regulation does our agreed best procedure not comply
with?

It's pointless discussing legality without reference to the law.

Look at an 8260-3 for any ILS approach. There is probably one or more
on the FAA's coordination web site today. The form is an individual
amendment to Part 97. It sets forth the courses, distances, minimum
altitudes, and location of P-FAF. It can be inferred from the context of
such regulatory document that the G/S is not the primary vertical
guidance mechanism prior to the P-FAF. That is the official view of
those who establish and implement the criteria.

This is reinforced by the fact that the AIM states that the lightening
bolt on NACO ILS charts (profile feather in Jepp charts) consitutes the
beginning of the ILS precision final approach segment. The FAA ILS
criteria for G/S obstacle clearance is not evaluated or used prior to
the PFAF. Intermediate and intial approach segment minimum barometric
altimetry fixes are used to define the vertical component of
intermediate and initial approach segments.