I agree with everything you say.
That's why I asked the question, because I am faced with several approach
plates which specify "Requires 50KHz Glideslope". I cannot find anything
about this in any documentation, so I have no idea what this note means.

I think what I'll do is fly a vor or loc approach at one of these and see if
the GS comes in on the KX155A. If so, I'll just guess that note is of no
importance, and relates to something very old and forgotten.



In article ,
says...


Hmmm.

How are these new frequencies being implemented? Do you have some
documentation?

Currently, each ILS frequency is channeled to a particular GS frequency.

Given 50kHz spacing, and given that the ILS frequencies are 108.10 to
111.95 (and given that if the Freq*10 is even, it is a VOR frequency),
there are only 40 available ILS channels in that frequency range:

e.g. 108.10
108.15
108.30
108.35
...

The 150kHz spacing from 329.15-335 also results in 40 GS frequencies.

So unless there is some change in the ILS specs, it seems odd that there
should be a change in the GS specs.

Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)