Can a failed Glide Slope also void the Localizer approach?

I had a question today that I've never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be un-executable
by regulation? I've always assumed that with the GS OTS I'd just revert
to the LOC, but are there approaches were the full ILS is approved but
the LOC only isn't? In other words, are there precision approaches where
vertical guidance is required and there is no non-precision alternative?

Jim Carter wrote:

Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be un-executable
by regulation? I've always assumed that with the GS OTS I'd just revert
to the LOC, but are there approaches were the full ILS is approved but
the LOC only isn't? In other words, are there precision approaches where
vertical guidance is required and there is no non-precision alternative?

I would think if there are localizer minimums published, you could
revert to the localizer should the GS go out.

Jim Carter wrote:
I had a question today that I’ve never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be un-executable
by regulation? I’ve always assumed that with the GS OTS I’d just revert
to the LOC, but are there approaches were the full ILS is approved but
the LOC only isn’t? In other words, are there precision approaches where
vertical guidance is required and there is no non-precision alternative?




As another has stated: If there is a published localizer only approach,
or if the ILS approach has published localizer only minimums, then you
can proceed with a localizer approach.

If there are no localizer only approaches or minima charted, then I
would suspect you cannot do the approach under IFR.

Dave

-----Original Message-----
From: Dave S [mailto Posted At: Wednesday, August 23, 2006 5:18 AM
Posted To: rec.aviation.ifr
Conversation: Can a failed Glide Slope also void the Localizer
approach?
Subject: Can a failed Glide Slope also void the Localizer
approach?

Jim Carter wrote:
I had a question today that I've never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be
un-executable
by regulation? I've always assumed that with the GS OTS I'd just
revert
to the LOC, but are there approaches were the full ILS is approved
but
the LOC only isn't? In other words, are there precision approaches
where
vertical guidance is required and there is no non-precision
alternative?




As another has stated: If there is a published localizer only
approach,
or if the ILS approach has published localizer only minimums, then you
can proceed with a localizer approach.

If there are no localizer only approaches or minima charted, then I
would suspect you cannot do the approach under IFR.

Dave

I think we all understand the concept of Localizer only approach
minimums, but my question was "... are there approaches were the full
ILS is approved but the LOC only isn't?" Does anyone know of a specific
airport?

-----Original Message-----
From: Dave S [mailto Posted At: Wednesday, August 23, 2006 5:18 AM
Posted To: rec.aviation.ifr
Conversation: Can a failed Glide Slope also void the Localizer
approach?
Subject: Can a failed Glide Slope also void the Localizer
approach?

Jim Carter wrote:
I had a question today that I've never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be
un-executable
by regulation? I've always assumed that with the GS OTS I'd just
revert
to the LOC, but are there approaches were the full ILS is approved
but
the LOC only isn't? In other words, are there precision approaches
where
vertical guidance is required and there is no non-precision
alternative?




As another has stated: If there is a published localizer only
approach,
or if the ILS approach has published localizer only minimums, then you
can proceed with a localizer approach.

If there are no localizer only approaches or minima charted, then I
would suspect you cannot do the approach under IFR.

Dave

I think we all understand the concept of Localizer only approach
minimums, but my question was "... are there approaches were the full
ILS is approved but the LOC only isn't?" Does anyone know of a specific
airport?

-----Original Message-----
From: Dave S [mailto Posted At: Wednesday, August 23, 2006 5:18 AM
Posted To: rec.aviation.ifr
Conversation: Can a failed Glide Slope also void the Localizer
approach?
Subject: Can a failed Glide Slope also void the Localizer
approach?

Jim Carter wrote:
I had a question today that I've never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be
un-executable
by regulation? I've always assumed that with the GS OTS I'd just
revert
to the LOC, but are there approaches were the full ILS is approved
but
the LOC only isn't? In other words, are there precision approaches
where
vertical guidance is required and there is no non-precision
alternative?




As another has stated: If there is a published localizer only
approach,
or if the ILS approach has published localizer only minimums, then you
can proceed with a localizer approach.

If there are no localizer only approaches or minima charted, then I
would suspect you cannot do the approach under IFR.

Dave

I think we all understand the concept of Localizer only approach
minimums, but my question was "... are there approaches were the full
ILS is approved but the LOC only isn't?" Does anyone know of a specific
airport?

I have not looked at every ILS to see the answer, but I
would guess that some standard or special [private] ILS
procedure at an airport with many obstructions or in the
mountains could require a GS and not be allowed otherwise.
To get the answer you need to reread the TERPS manual or
perhaps call Flight Standards in OKC and ask the experts.
At the pilot end, fly what is authorized on the chart and by
NOTAM.


"Jim Carter" wrote in message
news:00a401c6c6af$7009ba60$4001a8c0@omnibook6100.. .
|
|
| -----Original Message-----
| From: Dave S [mailto | Posted At: Wednesday, August 23, 2006 5:18 AM
| Posted To: rec.aviation.ifr
| Conversation: Can a failed Glide Slope also void the
Localizer
| approach?
| Subject: Can a failed Glide Slope also void the
Localizer
| approach?
|
| Jim Carter wrote:
| I had a question today that I've never considered, and
need the
| experience of the group.
|
|
|
| Are there airports with ILS approaches such that if
the Glide Slope
| component failed or went OTS, the entire approach
would be
| un-executable
| by regulation? I've always assumed that with the GS
OTS I'd just
| revert
| to the LOC, but are there approaches were the full ILS
is approved
| but
| the LOC only isn't? In other words, are there
precision approaches
| where
| vertical guidance is required and there is no
non-precision
| alternative?
|
|
|
|
| As another has stated: If there is a published localizer
only
| approach,
| or if the ILS approach has published localizer only
minimums, then you
| can proceed with a localizer approach.
|
| If there are no localizer only approaches or minima
charted, then I
| would suspect you cannot do the approach under IFR.
|
| Dave
|
| I think we all understand the concept of Localizer only
approach
| minimums, but my question was "... are there approaches
were the full
| ILS is approved but the LOC only isn't?" Does anyone know
of a specific
| airport?
|
|

Jim Carter wrote:

I had a question today that I’ve never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be un-executable
by regulation? I’ve always assumed that with the GS OTS I’d just revert
to the LOC, but are there approaches were the full ILS is approved but
the LOC only isn’t? In other words, are there precision approaches where
vertical guidance is required and there is no non-precision alternative?



Quite a few, such as Boeing Field, Arcata,California Reno, Butte,
Montana. All of those have a separate LOC procedure, which cannot be
switched to midsstream. Missula, Montana was an ILS that does not have
a separate LOC IAP.

It's all about being able to place stepdown fixes in accordance with
TERPs criteria (facility accuracy, fix displacement factor) rather than
with the continous, and varying with distance, electronic glide-path
obstacle clearance plane.

Jim Carter wrote:
I had a question today that I’ve never considered, and need the
experience of the group.



Are there airports with ILS approaches such that if the Glide Slope
component failed or went OTS, the entire approach would be un-executable
by regulation? I’ve always assumed that with the GS OTS I’d just revert
to the LOC, but are there approaches were the full ILS is approved but
the LOC only isn’t? In other words, are there precision approaches where
vertical guidance is required and there is no non-precision alternative?



There are some procedures that only have precision ILS minima published
on the procedure, so if the GS went OTS, then that procedure would not
be available simply because that procedure requires the glideslope and
has no LOC line of minima. If they have circling minima on the ILS then
there is a note "Circling requires descent on glideslope to MDA".
See the example at Butte, Montana;
http://www.naco.faa.gov/d-tpp/0608/00588I15.PDF
In that example, there is no non-precision alternative on that
particular plate, but there is a LOC procedure published on a separate
approach plate if you want to fly the LOC only procedure.
I don't know offhand if there are any ILS runways that have no "LOC
only" mins available at all.

JPH

JPH wrote:

I don't know offhand if there are any ILS runways that have no "LOC
only" mins available at all.

JPH

KMSO