Question from some hangar talk with a friend earlier. They maintain that there are ILS approaches "out west" that only bring you down to 400ft. agl instead of the standard. Also that there is not a category tied to these ILS's.
Now this doesn't sound too unusual, but i've never come across anything like this. Are there full ILS approaches that don't bring you down to at least 200?
Thanks in advance for the enlightenment.

Yes there are, KBOI 28r ILS brings you down to 250 AGL

Yes.

There are many reasons why an ILS may have higher than standard
minimums to include an obstacle or signal irregularities. If you can give me the airport or ILS identifier I'll see what I can find out for you.

And I bet most have at least 3/4 mile vis requirement too.

Not exactly "out west", but KBOS ILS RWY 27 has a CAT I Decision Altitude of 460', which is 443' above the TDZE of 17'.






.

KYIP...250, 3/4?


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Yes, this.

There even used to be LDA+glideslope approaches. All the hardware of an ILS, but you just couldn't call it an ILS. I think those are all gone now. The old definition of "a precision approach is one with vertical guidance" was obsolete decades ago, the FAA just never got around to fixing that until recently.

LDA/GS at AMA

http://155.178.201.160/d-tpp/1706/00019LDAD22.PDF

LOC transmitter offset to side of runway, due to its location doesn't meet criteria to be an ILS

I thought there may be a few. Show's what I know!
Thanks for the replies everyone.

It's usually due to obstacles that penetrate the standard protections of the 200-1/2 transition to visual segment. Not sure exactly what it is but TERPS/FAA has a specific criteria for obstacle protection on various segments of an approach. Similarly, instead of or including higher HATT you'll see a steeper glidepath.

On a similar note, if you ever see a non precision approach without a VDP published, it means there are obstacles protruding the protection area for a normal 3* glidepath, meaning depart the MDA at your own risk at night or IMC even with the runway clearly in sight.