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Old May 20th 06, 12:00 AM posted to rec.aviation.ifr
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Default Vector altitude for ILS below GS intercept altitude?

Here is a common occurance at TPL, Temple, TX which I use
as a way of teaching students how to stay ahead of ATC:

We are VFR doing practice approaches and being vectored
for an ILS to RWY 15. Usually this results in being vectored
to the west side of the airport and told to maintain 3000'. At
about 8 miles out, the final clearance goes something like this:

"Cessna xyxxz, you are 5 miles from the outer marker, turn right
heading 120 to intercept the localizer, maintin 3000 until established,
cleared for the ILS approach to runway 15 Temple."

Normally, by the time the localizer needle comes off the peg,
we have already flown trhough the glideslope and are well above
the glide slope at this point. The MVA in that area (according to
one controller) is 2600', but they routinely keep you at 3000' usless
you ask for lower. The glide slope intercept altitude is 1700'.

I tell my students to expect this, but the first couple of times it happens
to
them they always seem to get behind, don't ask for lower and/or end up
failing to decend soon enough to recover. Makes for a nice game of
catch-up as they try to get back on the glide slope. After a couple of
times, they wise up and either ask for lower before being given the
approach clearance, or they are spring loaded and ready to descend
once the localizer needle gets within 3/4 scale deflection.

Ronnie

"KP" nospam@please wrote in message
...
"M" wrote in message
oups.com...
Is it common for the approach controller to vector for an ILS at an
altitude below the GS intercept altitude on the IAP? Today is the
third time in the last year or so that Victoria terminal vectored me
for the ILS into BLI at 2000 feet, instead of 2100. I'm very familiar
with the area and I did not bother to question them.

The Canadian controllers provide approach service for Bellingham
probably from an agreement between FAA and NavCanada. Maybe the rules
are somewhat different in Canada, or they just don't have the right
information on this approach?

See http://204.108.4.16/d-tpp/0604/00045I16.PDF


As has already been pointed out, FAAO 7110.65 5-9-1b requires US
controllers to vector "For a precision approach, at an altitude not above
the glideslope/glidepath or below the minimum glideslope intercept
altitude specified on the approach procedure chart."

So...

What was your assigned altitude prior to receiving the approach clearance?
Above 2100 or level at 2000?

If above 2100, what was the wording of the actual approach clearance? Any
"at or above" or other wording that would allow you to adjust your descent
to intercept the GS at the "altitude specified on the approach chart"
rather than level at 2000?

It could also be as simple as the MVA in that area is 2000 and the
controllers simply assign the round thousands MVA as a routine. They
either don't know or don't care (given the allowable error in altimeters
and Mode C) that they are supposed to add that extra 100ft for ILS
approaches.