John Collins
En-Route
The approach is an old approach from 2009 and is a stand alone GPS approach. The new standard is the RNAV approach and the GPS stand alone approaches will be superseded over the next few years. There are only 290 of these type approaches still in the inventory. L45 is scheduled to have the approach upgraded to RNAV 9/20/12 with LPV minimums. I don't know what the real glidepath and TCH are coded into the database for this approach, but as a rough assumption, with a TCH of 40 feet and a 3 degree glidepath would put the nominal glidepath at 2030 feet at APCUD, which should be a small fly down (just under a half a dot) if you were on the glidepath on an ISA temperature day. Two and a half dots (assuming 5 dots are full scale) is more than I would expect and would represent the glidepath being approximately 200 feet lower than the FAF minimum verses 30 feet above the altitude. What does your CDI show during the startup self test page of your GPS, it should indicate half scale fly up. If this was off, then it would show up during the approach to the same degree.
Regardless, you have to honor the minimum altitude as you were doing rather than using the advisory glidepath, when there is a conflict between the two.
Regardless, you have to honor the minimum altitude as you were doing rather than using the advisory glidepath, when there is a conflict between the two.