Intercepting the ILS

[[email protected]]

Hello,

Yesterday I was out getting an IPC. We were doing the Stockton, CA
ILS. ATC
had us intercepting the localizer at 2000 feet. The altitude for
glideslope
interception is 1800 ( underlined ).

My old CFII taught me that the glideslope interception altitude on
the chart is a minimum altitude, and that it was fine to intercept it
higher. So I just tootled along
at 2000 - figuring it was simpler to do one configuration change at GS
interception
rather than three changes - one to descend the 200 feet, another to
level off, and
a third to intercept the glideslope.

The new CFII criticized this procedure and told me that the plate
specified 1800,
and it was wrong to intercept at 2000. Which one was right?

- Jerry Kaidor ( )

[[email protected]]

wrote:
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?
>
> - Jerry Kaidor ( )
>
The new CFI is technically correct but the old CFI is far more practical .

[Roy Smith]

> wrote:
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC had us intercepting the localizer at 2000 feet. The
> altitude for glideslope interception is 1800 ( underlined ).
> [...]
> The new CFII criticized this procedure and told me that the plate
> specified 1800, and it was wrong to intercept at 2000.

I can't see any reason not to intercept at 2000. I think your new guy
is full of it.

[Mark Hansen]

On 01/26/06 07:17, wrote:
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?
>
> - Jerry Kaidor ( )
>

I was taught to never intercept the GS from above, due to signal echoes,
etc.

However, there are cases where you're vectored in at a higher altitude.
In this case, you'll actually intercept the GS at the higher altitude
further out from the normal interception point.

You can go ahead and follow this signal down, as a way to get to the
OM at, in this case, 1758'. If you're too high when you get to the
OM, then you're not on the correct GS signal, and you should execute
a missed approach.


--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

[Robert Chambers]

I don't have the plate but did the controller clear you for the approach
2000 till established on the localizer?

If you're established with the loc withiin a couple of dots of the
center - which you should be prior to the FAF then there's no harm in
being at 1800' to do the intercept. Staying at 2000 is ok, you will
just intercept the GS a couple of handfull of seconds earlier than you
would at 1800'.

Were you timing the approach as well for when the GS goes out of service
as they sometimes do on IPC rides? the timer should start at the FAF
which can be a busy time if you're going down, staying centered,
maintaining airspeed, calling the tower at FAF if that's what they
wanted, etc.

Robert
wrote:
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?
>
> - Jerry Kaidor ( )
>

[Nathan Young]

On 26 Jan 2006 07:17:15 -0800, " > wrote:

>Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
>ILS. ATC
>had us intercepting the localizer at 2000 feet. The altitude for
>glideslope
>interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
>the chart is a minimum altitude, and that it was fine to intercept it
>higher. So I just tootled along
>at 2000 - figuring it was simpler to do one configuration change at GS
>interception
>rather than three changes - one to descend the 200 feet, another to
>level off, and
>a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
>specified 1800,
>and it was wrong to intercept at 2000. Which one was right?

ATC should have cleared you to maintain 2000 until established, and
that is exactly what I would have done.

Regarding your new CFII's comment. I believe he is confusing this
issue with intercepting the GS from above.

-Nathan

[Garner Miller]

In article . com>,
"> wrote:

> The altitude for glideslope interception is 1800 ( underlined ).

> ... So [during IPC] I just tootled along at 2000 - figuring it was
> simpler to do one configuration change at GS interception rather than
> three changes - one to descend the 200 feet, another to level off,
> and a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800, and it was wrong to intercept at 2000. Which one
> was right?

You (and your old CFI) were.

1800 is the minimum altitude; that's why it's underlined only on the
bottom of the number on the NACO charts. If it were mandatory, it
would have lines above and below (or the word "Mandatory" on Jepp
charts), and you would have to go down to 1800.

I use the same technique you did every day flying for my airline.
Making an unnecessary 200' step-down-and-level-off is a waste of time
and effort, and makes more motion for the passengers to feel.

--
Garner R. Miller
ATP/CFII/MEI
Clifton Park, NY =USA=
http://www.garnermiller.com/

[Peter R.]

" > wrote:

> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?

IMO, you did right, as you were still below the glideslope.

This scenario is very similar to my home airport:

ILS 28 at Syracuse, NY:
http://www.myairplane.com/databases/approach/pdfs/00411I28.PDF

Glideslope intercept is at the outer marker at 1800 feet, but ATC almost
always vectors aircraft to intercept the localizer a few miles before the
outer marker and descends the aircraft to 2,100 with the instruction,
"Maintain 2,100 'till established, cleared for the ILS 28..."

I am of the same opinion as you because I fly a retractable gear aircraft.
Gear comes out at glideslope intercept (regardless of where this happens
along the glideslope), aircraft slows and begins a nice 500-600 fpm descent
on its own. Thus, as long as I have descended to 2,100 feet and have been
vectored a couple miles or so before the outer marker, I will still be
below the glideslope. No need to dick around with a further descent to
lose those additional 300 feet with gear and flaps still retracted.

The only caveat is that when I reach the outer marker (already coming down
the glideslope at this point), I quickly confirm that the altimeter's
altitude reading matches the altitude shown on the plate.



--
Peter

[Peter R.]

"Peter R." > wrote:

> IMO, you did right, as you were still below the glideslope.

BYW, while it is true that your CFI may have been technically correct, IMO
it was incorrect of him to criticise your method and label it "wrong."

--
Peter

[Garner Miller]

In article >, Robert
Chambers > wrote:

>
> Were you timing the approach as well for when the GS goes out of service
> as they sometimes do on IPC rides? the timer should start at the FAF
> which can be a busy time if you're going down, staying centered,
> maintaining airspeed, calling the tower at FAF if that's what they
> wanted, etc.

The Final Approach Point (not fix) on an ILS is the published
glideslope altitude (in this case, 1800) intersecting with the
glideslope. That's NOT where the timer for a LOC approach would
start, because there's no glideslope to define the point!

The FAF on the nonprecision localizer-only approach is normally a DME
fix, an intersection, or a marker, and it's /that/ point that's defined
by the maltese cross (and where the clock starts). In the case of
Stockton's ILS 29R, it's a LOM, and you're already on your way down the
glideslope by then, if you're flying the full ILS, whether you've
intercepted at 2000 feet or 1800 feet.


The chart's here in case anyone else wants to see it:
http://www.naco.faa.gov/d-tpp/0601/00407I29R.PDF

--
Garner R. Miller
ATP/CFII/MEI
Clifton Park, NY =USA=
http://www.garnermiller.com/

[[email protected]]

Your procedure is just fine - better because it is simpler.
Certainly legal because 1800 is a minimum, not a mandatory altitude.
However:

(1) For a localizer-only approach, you would want to make the descent
to 1800 prior to JOTLY to avoid an unnecessarily steep final descent.
(2) When following the glideslope, you are still responsible for
meeting any crossing restrictions,. A good example is the CIVET 4 STAR
into LAX http://naco.faa.gov/d-tpp/0601/00237CIVET.PDF
On a standard day, following the GS will meet the crossing
restrictions, but on a hot day it may not (the pressure levels are
higher). This can result in loss of separation with IFR traffic
crossing below. Pilots have been busted for this.
(3) Another reason to pay attention to step-down altitudes while
following ther glideslope is that it isn't certified for use or flight
tested at arbitrarily large distances from the antenna.


I would continue flying it your way. Likewise on the ILS 25R into
LVK from TRACY, I always stay at 3300 until intercepting the
glideslope, rather than descending first to 2800. There can be nasty
up and downdrafts over the Altamont. There's no need to expose
yourself to them at an unnecessarily low altitude.

Ed (LVK CFII)
http://williams.best.vwh.net/


wrote:
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?
>
> - Jerry Kaidor ( )

[[email protected]]

Roy Smith wrote:

> > wrote:
>
>>Yesterday I was out getting an IPC. We were doing the Stockton, CA
>>ILS. ATC had us intercepting the localizer at 2000 feet. The
>>altitude for glideslope interception is 1800 ( underlined ).
>>[...]
>>The new CFII criticized this procedure and told me that the plate
>>specified 1800, and it was wrong to intercept at 2000.
>
>
> I can't see any reason not to intercept at 2000. I think your new guy
> is full of it.

As a matter of regulation, the G/S is to be used as primary vertical
guidance only from the PFAF inbound. There are some places, where early
use of the G/S has resulted in airspace violations, LAX being the most
notable.

In the case cited, the CFI is nitpicking but is nonetheless legally correct.

[Robert M. Gary]

It depends. If you look at the ILS for MHR (Mather, just north of where
you were), you are below the glideslope for most of the approach. There
are several step downs on the approach.
However, from a real world point of view, when I've shot the ILS into
Stockton in fog, I remember just flying the GS because I was lazy.
-Robert

[Bob Gardner]

FWIW, I have been chewed out by Seattle Approach for intercepting higher
than the published GSIA of 2200 for the ILS 13R.


> wrote in message
oups.com...
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?
>
> - Jerry Kaidor ( )
>

[Garner Miller]

In article >, Bob Gardner
> wrote:

> FWIW, I have been chewed out by Seattle Approach for intercepting higher
> than the published GSIA of 2200 for the ILS 13R.

For which airport?

[Garner Miller]

In article >, Bob Gardner
> wrote:

> FWIW, I have been chewed out by Seattle Approach for intercepting higher
> than the published GSIA of 2200 for the ILS 13R.

Nevermind the "Which airport" question if my cancel didn't work, I
found it; Boeing field, I assume.

I can't see why they would have chewed you out -- if the instruction
was something like "Maintain 2500 until established on the localizer,
cleared the ILS 13R," you did nothing improper. If he wanted you at
2200, he should have instructed you to do so; the chart only lists it
as a minimum altitude, as most do.

What if you weren't DME-equipped? How would you know you were within
10NM of NOLLA, and thus safe to descend to 2200? You really wouldn't,
unless you had done the procedure turn, or the controller had cleared
you with a "You're X miles from NOLLA" (and X happened to be less than
10 miles).

--
Garner R. Miller
ATP/CFII/MEI
Clifton Park, NY =USA=
http://www.garnermiller.com/

[Doug]

I can tell you that I have been told to intercept the ILS at altitudes
well above the glideslope intercept altitude at the FAF by ATC. I have
been cleared for the approach outside of the FAF. I followed their
instructions and flew the approach. Never have had a problem. I don't
see what the problem is, so long as you are intercepting the glideslope
from below, and so long as you are at least as high as is charted you
should be. So long as you make sure you are at the proper altitude when
you cross the FAF, I don't see the problem. Unless I see it as unsafe
or some obvious violation, I do what ATC tells me to do.

What did your CFI tell you to do? Decline ATC's instruction? If you do
that, the ATC guy is going to be confused and probably ask you what it
is you want to do. In which case you can tell him that you want to go
down to 1800' and intercept there. Ok, descend to 1800', intercept and
cleared. Not much different than what you did, now is it? In the
meantime, the freq is crowded and in all the confusion someone else is
hosed, maybe you too as ATC might have to leave you and talk to someone
else. Or maybe, in the meantime your plane has gotten out of shape
(have fun going missed). To some extent we pilots have to rely on ATC
to be telling us to do the right thing. Sure, watch out for being
cleared into a mountain, but something like this seems ok to me.....

Some pilots take the tactic not to have ATC control them, but have them
control ATC by telling ATC what they are going to do and that they
expect that as their clearance. You can try that approach, but
sometimes it backfires. Me, I have discovered I can't fly the airplane
and do ATC's job too. But then I rarely have the luxury of a copilot.

[Doug]

Another comment I would make is if you decline ATC's instruction at
this point, you are probably going to end up going missed (or
intercepting the glideslope from above).

[Robert Chambers]

Garner Miller wrote:
> In article >, Robert
> Chambers > wrote:
>
>
>>Were you timing the approach as well for when the GS goes out of service
>>as they sometimes do on IPC rides? the timer should start at the FAF
>>which can be a busy time if you're going down, staying centered,
>>maintaining airspeed, calling the tower at FAF if that's what they
>>wanted, etc.
>
>
> The Final Approach Point (not fix) on an ILS is the published
> glideslope altitude (in this case, 1800) intersecting with the
> glideslope. That's NOT where the timer for a LOC approach would
> start, because there's no glideslope to define the point!

In this instance there's a 5.3 DME defining the FAF, and the Outer
Marker it's 4/10th of a mile from GS intercept. It's a busy time. I
didn't say he started timing at GS intercept at 1800, I believe I did
say at the FAF. With an IPC you expect things like GS's to fail which
adds to the workload. Thats all I meant.

[Dave Butler]

Doug wrote:
> I can tell you that I have been told to intercept the ILS at altitudes
> well above the glideslope intercept altitude at the FAF by ATC. I have
> been cleared for the approach outside of the FAF. I followed their
> instructions and flew the approach. Never have had a problem. I don't
> see what the problem is, so long as you are intercepting the glideslope
> from below, and so long as you are at least as high as is charted you
> should be. So long as you make sure you are at the proper altitude when
> you cross the FAF, I don't see the problem. Unless I see it as unsafe
> or some obvious violation, I do what ATC tells me to do.

The OP didn't say what ATC's instruction was, so we don't know. I don't think
ATC's instruction is relevant to the OP's question. The OP just wanted to know
whether descent to 1800 was mandatory. As far as we know, ATC didn't instruct
the OP one way or the other.

<snip>

[[email protected]]

wrote:
> Roy Smith wrote:
>
> > > wrote:
> >
> >>Yesterday I was out getting an IPC. We were doing the Stockton, CA
> >>ILS. ATC had us intercepting the localizer at 2000 feet. The
> >>altitude for glideslope interception is 1800 ( underlined ).
> >>[...]
> >>The new CFII criticized this procedure and told me that the plate
> >>specified 1800, and it was wrong to intercept at 2000.
> >
> >
> > I can't see any reason not to intercept at 2000. I think your new guy
> > is full of it.
>
> As a matter of regulation, the G/S is to be used as primary vertical
> guidance only from the PFAF inbound. There are some places, where early
> use of the G/S has resulted in airspace violations, LAX being the most
> notable.

Let's be argumentative here. What regulation are you referring to?
In the case of LAX (the Civet 4 arrival I quoted earlier), the
problem was that following the glideslope caused the airplane to
violate published crossing restrictions.
>
> In the case cited, the CFI is nitpicking but is nonetheless legally correct.

At SCK there was no crossing restriction either given in the
clearance or published. The pilot is free to descend *at his
discretion* from 2000 to 1800. Following the glideslope is a perfectly
acceptable way of doing that. The CFI is not only nit-picking, but in
this instance is wrong. Not only that, but he's making additional
unnecessary work.

[Bob Gardner]

We intercepted at 3000 and rode it down more out of inertia than anything
else. We did have a "maintain 2200" instruction while at three but not a
"descend and maintain." As I recall, I was coming from the northwest and had
picked up the localizer 20 miles or so out. Three is pretty popular around
here for the lowest altitude prior to an approach, and in retrospect I think
the controller just wanted me to make a hole for someone else to fit into.
Gotta admit I felt a little sheepish about getting called on it because I
knew better.
"Garner Miller" > wrote in message
...
> In article >, Bob Gardner
> > wrote:
>
>> FWIW, I have been chewed out by Seattle Approach for intercepting higher
>> than the published GSIA of 2200 for the ILS 13R.
>
> Nevermind the "Which airport" question if my cancel didn't work, I
> found it; Boeing field, I assume.
>
> I can't see why they would have chewed you out -- if the instruction
> was something like "Maintain 2500 until established on the localizer,
> cleared the ILS 13R," you did nothing improper. If he wanted you at
> 2200, he should have instructed you to do so; the chart only lists it
> as a minimum altitude, as most do.
>
> What if you weren't DME-equipped? How would you know you were within
> 10NM of NOLLA, and thus safe to descend to 2200? You really wouldn't,
> unless you had done the procedure turn, or the controller had cleared
> you with a "You're X miles from NOLLA" (and X happened to be less than
> 10 miles).
>
> --
> Garner R. Miller
> ATP/CFII/MEI
> Clifton Park, NY =USA=
> http://www.garnermiller.com/

[Dave Butler]

wrote:
> Hello,
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC
> had us intercepting the localizer at 2000 feet. The altitude for
> glideslope
> interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along
> at 2000 - figuring it was simpler to do one configuration change at GS
> interception
> rather than three changes - one to descend the 200 feet, another to
> level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800,
> and it was wrong to intercept at 2000. Which one was right?

My first thought was, "your old CFII" was right.

I certainly would have done exactly what you did, and had no heartburn over it.

OTOH, that got me wondering how much above the published glide slope intercept
altitude I would accept. To take an extreme example to illustrate the question
(not a realistic example, of course) suppose ATC had you intercepting the
localizer at 10000 feet.

For the purposes of the thought experiment, assume this still allows you to
intercept the glide slope from below. Could you be confident that the glide
slope had been flight-checked up to 10000 feet? No. You also don't know that
it's been flight checked to 2000 feet. Where do you draw the line?

Dave

[Mark Hansen]

On 01/26/06 11:14, Dave Butler wrote:
> wrote:
>> Hello,
>>
>> Yesterday I was out getting an IPC. We were doing the Stockton, CA
>> ILS. ATC
>> had us intercepting the localizer at 2000 feet. The altitude for
>> glideslope
>> interception is 1800 ( underlined ).
>>
>> My old CFII taught me that the glideslope interception altitude on
>> the chart is a minimum altitude, and that it was fine to intercept it
>> higher. So I just tootled along
>> at 2000 - figuring it was simpler to do one configuration change at GS
>> interception
>> rather than three changes - one to descend the 200 feet, another to
>> level off, and
>> a third to intercept the glideslope.
>>
>> The new CFII criticized this procedure and told me that the plate
>> specified 1800,
>> and it was wrong to intercept at 2000. Which one was right?
>
> My first thought was, "your old CFII" was right.
>
> I certainly would have done exactly what you did, and had no heartburn over it.
>
> OTOH, that got me wondering how much above the published glide slope intercept
> altitude I would accept. To take an extreme example to illustrate the question
> (not a realistic example, of course) suppose ATC had you intercepting the
> localizer at 10000 feet.
>
> For the purposes of the thought experiment, assume this still allows you to
> intercept the glide slope from below. Could you be confident that the glide
> slope had been flight-checked up to 10000 feet? No. You also don't know that
> it's been flight checked to 2000 feet. Where do you draw the line?
>
> Dave

The other thing to remember is that when you are backed-up from the
Final Approach Point, you know you will intercept the GS at a higher
altitude, but where exactly? After all, if you are too high, you
could be picking up an erroneous echo of the GS signal.

This is part of the risk (minor that it is) in doing this - because
if you follow the signal down to the outer marker (in the OP's case)
and are not at the correct GS altitude, you probably should go missed.

However, in the real world, ATC isn't going to vector you in this way
if the altitude wouldn't intercept the actual GS signal, so although
the pilot should remain vigilant and watch for things to go south, it will
generally work out.

--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

[Garner Miller]

In article <1138302691.662580@sj-nntpcache-5>, Dave Butler >
wrote:

> ...suppose ATC had you intercepting the localizer at 10000 feet.
>
> For the purposes of the thought experiment, assume this still allows
> you to intercept the glide slope from below. Could you be confident
> that the glide slope had been flight-checked up to 10000 feet? No.
> You also don't know that it's been flight checked to 2000 feet. Where
> do you draw the line?

You draw the line by looking at the profile view on the approach chart,
ensuring that you're above the step-downs as the appropriate point.
(One some approaches, as other posters noted, the glideslope will put
you below some of these crossing restrictions. Fuzzy memories tell me
BOS ILS27 used to be like that, but it isn't anymore.)

As long as you're cross-checking your altitudes to ensure you're above
the minimum crossing altitudes, there's no problem at all following the
glideslope down from farther out. It's *vitally* important to check
the glideslope crossing altitude at marker, of course, to ensure that
you're not on a false glideslope.

--
Garner R. Miller
ATP/CFII/MEI
Clifton Park, NY =USA=
http://www.garnermiller.com/

[[email protected]]

As long as your resulting flight path complies with your clearance
and the published altitude restrictions on the approach plate, you are
free to descend at your discretion. If that just happens to follow the
apparent glideslope, valid or not, it is immaterial.
You only get into trouble if following the glideslope causes you to
violate an altitude restriction.

[Ron Rosenfeld]

On Thu, 26 Jan 2006 09:29:10 -0800, wrote:


>
>As a matter of regulation, the G/S is to be used as primary vertical
>guidance only from the PFAF inbound. There are some places, where early
>use of the G/S has resulted in airspace violations, LAX being the most
>notable.
>
>In the case cited, the CFI is nitpicking but is nonetheless legally correct.

Huh? What regulation?

Published guidance in the AIM indicates that the GS is generally usable out
to ten miles, but this may be extended at certain locations.




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

[JPH]

wrote:

>
> As a matter of regulation, the G/S is to be used as primary vertical
> guidance only from the PFAF inbound. There are some places, where early
> use of the G/S has resulted in airspace violations, LAX being the most
> notable.
>
> In the case cited, the CFI is nitpicking but is nonetheless legally
> correct.

Tim,

Can you give an example of how an airspace violation could occur? It
seems that as long as the pilot doesn't descend below the minimum
altitude published for the segment of the approach he's in, then
descending on the glidepath can't put the aircraft any lower than
dropping down immediately to the minimum segment altitude at the
beginning of the segment. If he's in the Intermediate, then the
glidepath will more than likely keep him higher than dropping down to
the minimum altitude due to the length of the intermediate normally
compensating for the required altitude loss at 150 ft per mile optimum.
If the airspace violation would be from the aircraft being too high,
then perhaps the procedure should have a maximum altitude shown or the
controller issue a crossing restriction.
The glideslope intercept altitude is a minimum altitude, not a mandatory
or maximum altitude. From a TERPS standpoint there's no problem with
descending on the glideslope from 2000 on the procedure in question
instead of 1800.
If the pilot uses the glideslope for backup vertical guidance to give a
smooth transition to the final segment (while using the altimeter
readout outside the FAF to ensure he doesn't descend below 1800) then
what's wrong with that?

JPH

[[email protected]]

JPH wrote:

> Can you give an example of how an airspace violation could occur? It
> seems that as long as the pilot doesn't descend below the minimum
> altitude published for the segment of the approach he's in, then
> descending on the glidepath can't put the aircraft any lower than
> dropping down immediately to the minimum segment altitude at the
> beginning of the segment. If he's in the Intermediate, then the
> glidepath will more than likely keep him higher than dropping down to
> the minimum altitude due to the length of the intermediate normally
> compensating for the required altitude loss at 150 ft per mile optimum.
> If the airspace violation would be from the aircraft being too high,
> then perhaps the procedure should have a maximum altitude shown or the
> controller issue a crossing restriction.

It's happen at LAX quite a few times when the air is hot and the
underlying Ontario airspace rises to provide less than 1,000 feet of
vertical on the LAX G/Ses. The G/S doesn't move.

> The glideslope intercept altitude is a minimum altitude, not a mandatory
> or maximum altitude. From a TERPS standpoint there's no problem with
> descending on the glideslope from 2000 on the procedure in question
> instead of 1800.

True enough, and if the pilot wants to remain above the G/S that is
perfectly legal. But, any charted minimum stepdown altitudes prior to
the PFAF are governing, not the G/S.

> If the pilot uses the glideslope for backup vertical guidance to give a
> smooth transition to the final segment (while using the altimeter
> readout outside the FAF to ensure he doesn't descend below 1800) then
> what's wrong with that?

Nothing wrong with that.

[[email protected]]

wrote:

> wrote:
>
>>Roy Smith wrote:
>>

>
> Let's be argumentative here. What regulation are you referring to?
> In the case of LAX (the Civet 4 arrival I quoted earlier), the
> problem was that following the glideslope caused the airplane to
> violate published crossing restrictions.

In the Los Angeles case the violations occurred inside the CIVET
arrival, actually on the ILS profile. Those fixes are issued under Part
97 just as it the legal point at which the G/S *controls* for
descent(the PFAF).
>
>>In the case cited, the CFI is nitpicking but is nonetheless legally correct.
>
>
> At SCK there was no crossing restriction either given in the
> clearance or published. The pilot is free to descend *at his
> discretion* from 2000 to 1800. Following the glideslope is a perfectly
> acceptable way of doing that. The CFI is not only nit-picking, but in
> this instance is wrong. Not only that, but he's making additional
> unnecessary work.
>

I agree that the CFI is procedurally wrong, although legally correct.
Let me put it another way: the CFI is stuck on one aspect of the issue,
the other being that the pilot can make certain elections so long as he
does not use the G/S as primary for descent prior to the PFAF. The CFI
has a duty to teach resonable procedure while pointing out the legal
nuances of when the G/S is primary for altitude control. It sounds like
he covered only one aspect of the issue, which while correct legally, is
incorrect and out of context procedurally.

[David Cartwright]

> wrote in message
oups.com...
> The new CFII criticized this procedure and told me that the plate
> specified 1800, and it was wrong to intercept at 2000. Which one was
> right?

Assuming that by intercepting at 2,000 feet you're not infringing any other
published rules (e.g. airspace or specific instructions on the approach
plate) I would suggest you look at the published range for the ILS signal.
So long as you're within the published range of the glideslope signal when
doing a 2000' intercept, I can't see you're doing anything wrong -
particularly as you were presumably doing as you'd been told by an
authoritative controller. After all, it's common to fly the first bit of an
approach according to the book and then to take different instructions from
the controller.

D.

[[email protected]]

David Cartwright wrote:

>
> Assuming that by intercepting at 2,000 feet you're not infringing any other
> published rules (e.g. airspace or specific instructions on the approach
> plate) I would suggest you look at the published range for the ILS signal.
> So long as you're within the published range of the glideslope signal when
> doing a 2000' intercept, I can't see you're doing anything wrong -
> particularly as you were presumably doing as you'd been told by an
> authoritative controller. After all, it's common to fly the first bit of an
> approach according to the book and then to take different instructions from
> the controller.

The published range of a G/S has little practical meaning to a pilot.
Unlike service volumes for VORs it has no flight plan or route
limitation aspect.

If you can receive the G/S prior to the PFAF, its only advisory in any
case, so you are free to use it as you choose, provided you don't
violate any minimum segment altitude or stepdown fixes or any aspect of
an ATC clearance.

[[email protected]]

>> If the pilot uses the glideslope for backup vertical guidance to give a
>> smooth transition to the final segment (while using the altimeter
>> readout outside the FAF to ensure he doesn't descend below 1800) then
>> what's wrong with that?

>Nothing wrong with that.

That isn't really correct either. There's no necessity to monitor
the altimeter at SCK because there's no step-down fixes or other
crossing restrictions at issue. Above 1800 feet on the glideslope, the
glideslope is advisory, but the pilot is perforce satisfying the >=1800
foot minimum altitude requirement. Below 1800 feet the glideslope
becomes primary. So in practical terms nothing happens at 1800 feet.
There's nothing to monitor. (OK. I know, you part 121 types have now
reached a point where the weather can below minimums without
necessitating a miss.)

At *Stockton* (the subject of the question), there is no legal issue.
At LAX on the Civet arrival, and other situations where there are
step-down altitudes on the localizer outside the PFAF, there is a
potential issue. The step down minima take precedence over the GS
altitude.

[Jim Macklin]

The altitude at the marker is a double check on the
altimeter and the glide slope. If the altimeter is set
incorrectly or broken or if you have intercepted the wrong
glide slope lobe, the pilot has an opportunity to catch the
error and figure out what is wrong.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


> wrote in message
oups.com...
| >> If the pilot uses the glideslope for backup vertical
guidance to give a
| >> smooth transition to the final segment (while using the
altimeter
| >> readout outside the FAF to ensure he doesn't descend
below 1800) then
| >> what's wrong with that?
|
| >Nothing wrong with that.
|
| That isn't really correct either. There's no necessity
to monitor
| the altimeter at SCK because there's no step-down fixes or
other
| crossing restrictions at issue. Above 1800 feet on the
glideslope, the
| glideslope is advisory, but the pilot is perforce
satisfying the >=1800
| foot minimum altitude requirement. Below 1800 feet the
glideslope
| becomes primary. So in practical terms nothing happens at
1800 feet.
| There's nothing to monitor. (OK. I know, you part 121
types have now
| reached a point where the weather can below minimums
without
| necessitating a miss.)
|
| At *Stockton* (the subject of the question), there is no
legal issue.
| At LAX on the Civet arrival, and other situations where
there are
| step-down altitudes on the localizer outside the PFAF,
there is a
| potential issue. The step down minima take precedence over
the GS
| altitude.
|

[[email protected]]

>The altitude at the marker is a double check on the
>altimeter and the glide slope. If the altimeter is set
>incorrectly or broken or if you have intercepted the wrong
>glide slope lobe, the pilot has an opportunity to catch the
>error and figure out what is wrong.

That is of course true - but it's a different altitude, 1758 in this
case. It's the 1800 altiitude that loses significance once the GS has
been intercepted.

BTW, the chances of following the wrong lobe of the GS to the FAF
without noticing a problem is close to nil. It either has reverse
sensing or requires ridiculous rates of descent.

[[email protected]]

wrote:
>>>If the pilot uses the glideslope for backup vertical guidance to give a
>>>smooth transition to the final segment (while using the altimeter
>>>readout outside the FAF to ensure he doesn't descend below 1800) then
>>>what's wrong with that?
>
>
>>Nothing wrong with that.
>
>
> That isn't really correct either. There's no necessity to monitor
> the altimeter at SCK because there's no step-down fixes or other
> crossing restrictions at issue. Above 1800 feet on the glideslope, the
> glideslope is advisory, but the pilot is perforce satisfying the >=1800
> foot minimum altitude requirement. Below 1800 feet the glideslope
> becomes primary. So in practical terms nothing happens at 1800 feet.
> There's nothing to monitor. (OK. I know, you part 121 types have now
> reached a point where the weather can below minimums without
> necessitating a miss.)
>
> At *Stockton* (the subject of the question), there is no legal issue.
> At LAX on the Civet arrival, and other situations where there are
> step-down altitudes on the localizer outside the PFAF, there is a
> potential issue. The step down minima take precedence over the GS
> altitude.
>
We are procedurally in violent agreement. Nonetheless, the G/S is not
primary prior to the PFAF, any minimum altitude constraints
notwithstanding. That is the legalese of Part 97. I am just the messenger.

[[email protected]]

>We are procedurally in violent agreement. Nonetheless, the G/S is not
>primary prior to the PFAF, any minimum altitude constraints
>notwithstanding. That is the legalese of Part 97. I am just the messenger.

We're agreed that at SCK following the glide slope down from the 2000
foot vector altitude is the best procedure. We're also agreed that the
G/S is not primary outside the PFAF. Instead, one must abide by the
published altitudes - in this case we must remain above 1800 until this
PFAF. At SCK, this is logically guaranteed by our "best procedure".

However, I detect that your position is still that some sufficiently
zealous FAA inspector could violate me for using the G/S to descend to
1800. (otherwise how could the new instructor be "technically
correct"?). I disagree. If that is your position, please cite which
verse of Part 97 that this zealous inspector could attempt to violate
me on? Which regulation does our agreed best procedure not comply
with?

It's pointless discussing legality without reference to the law.

[[email protected]]

wrote:
>>We are procedurally in violent agreement. Nonetheless, the G/S is not
>>primary prior to the PFAF, any minimum altitude constraints
>>notwithstanding. That is the legalese of Part 97. I am just the messenger.
>
>
> We're agreed that at SCK following the glide slope down from the 2000
> foot vector altitude is the best procedure. We're also agreed that the
> G/S is not primary outside the PFAF. Instead, one must abide by the
> published altitudes - in this case we must remain above 1800 until this
> PFAF. At SCK, this is logically guaranteed by our "best procedure".
>
> However, I detect that your position is still that some sufficiently
> zealous FAA inspector could violate me for using the G/S to descend to
> 1800. (otherwise how could the new instructor be "technically
> correct"?). I disagree. If that is your position, please cite which
> verse of Part 97 that this zealous inspector could attempt to violate
> me on? Which regulation does our agreed best procedure not comply
> with?
>
> It's pointless discussing legality without reference to the law.
>
Look at an 8260-3 for any ILS approach. There is probably one or more
on the FAA's coordination web site today. The form is an individual
amendment to Part 97. It sets forth the courses, distances, minimum
altitudes, and location of P-FAF. It can be inferred from the context of
such regulatory document that the G/S is not the primary vertical
guidance mechanism prior to the P-FAF. That is the official view of
those who establish and implement the criteria.

This is reinforced by the fact that the AIM states that the lightening
bolt on NACO ILS charts (profile feather in Jepp charts) consitutes the
beginning of the ILS precision final approach segment. The FAA ILS
criteria for G/S obstacle clearance is not evaluated or used prior to
the PFAF. Intermediate and intial approach segment minimum barometric
altimetry fixes are used to define the vertical component of
intermediate and initial approach segments.

[[email protected]]

Garner Miller wrote:

> It's *vitally* important to check
> the glideslope crossing altitude at marker, of course, to ensure that
> you're not on a false glideslope.
>

The first false G/S above the normal G/S is typically 1500 higher at the
P-FAF. Only in extreme situations is it possible to intercept the false
G/S. And, of course, if you did, it would cause twice the descent rate
you expected once stablized on final approach.

[[email protected]]

I agree with everything you just wrote. But, you have not addressed
my question. In what way does/can following the glideslope from 2000
to 1800 feet at SCK violate the regulatory implications of the SCK
ILS's 8260-3?

There is no rule that says "thou shalt not follow the G/S unless it
is primary". What the rules say is "thou shall not bust the published
altitude restrictions prior to the PFAF".

Since it isn't logically possible to violate the altitude
restrictions *in this instance* by following the G/S, it can't be
illegal to do so.

The regulatory basis is 91.175(a) which requires "Unless otherwise
authorized by the Administrator, when an instrument letdown to a civil
airport is necessary, each person operating an aircraft, except a
military aircraft of the United States, shall use a standard instrument
approach procedure prescribed for the airport in part 97 of this
chapter."

Part 97 does not prescribe pilot technique. It prescribes the tracks
and altitudes to be flown. If those are complied with, there's no
possible violation.

[[email protected]]

What I'm having difficulty reconciling is the following statements of
yours:

"If you can receive the G/S prior to the PFAF, it's only advisory in
any
case, so you are free to use it as you choose, provided you don't
violate any minimum segment altitude or stepdown fixes or any aspect of
an ATC clearance."

I totally agree.

"The new CFI is technically correct but the old CFI is far more
practical."
"In the case cited, the CFI is nitpicking but is nonetheless legally
correct."
"I agree that the CFI is procedurally wrong, although legally correct."


So how can you assert these, *given that in this instance* it is
physically and logically impossible to "violate any minimum segment
altitude or stepdown fixes or any aspect of
an ATC clearance", because
a) the ATC clearance was to maintain 2000 until intercepting the
localizer, and
b) the procedure was to descend on the glide slope to the minimum
segment altitude (1800) at which point the G/S becomes primary.

The point is that blindly following the glideslope has the potential
at places *other than SCK* of causing violations of published
altitudes. Following the G/S is not a violation per se, busting
published or ATC assigned altitudes is.
The CFI is not "technically correct" or "legally correct". What he
could have said, after the flight, is that if one chooses to follow the
G/S prior to the PFAF one needs to be mindful that published and ATC
assigned altitudes have to be complied with, but that at SCK that was
not an issue.

[Jim Macklin]

If an altitude is underlined, it is the MINIMUM altitude...
if an altitude is over-lined it is the maximum altitude. If
it is both under and over-lined the altitude is mandatory.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


> wrote in message
oups.com...
| What I'm having difficulty reconciling is the following
statements of
| yours:
|
| "If you can receive the G/S prior to the PFAF, it's only
advisory in
| any
| case, so you are free to use it as you choose, provided
you don't
| violate any minimum segment altitude or stepdown fixes or
any aspect of
| an ATC clearance."
|
| I totally agree.
|
| "The new CFI is technically correct but the old CFI is far
more
| practical."
| "In the case cited, the CFI is nitpicking but is
nonetheless legally
| correct."
| "I agree that the CFI is procedurally wrong, although
legally correct."
|
|
| So how can you assert these, *given that in this
instance* it is
| physically and logically impossible to "violate any
minimum segment
| altitude or stepdown fixes or any aspect of
| an ATC clearance", because
| a) the ATC clearance was to maintain 2000 until
intercepting the
| localizer, and
| b) the procedure was to descend on the glide slope to the
minimum
| segment altitude (1800) at which point the G/S becomes
primary.
|
| The point is that blindly following the glideslope has
the potential
| at places *other than SCK* of causing violations of
published
| altitudes. Following the G/S is not a violation per se,
busting
| published or ATC assigned altitudes is.
| The CFI is not "technically correct" or "legally
correct". What he
| could have said, after the flight, is that if one chooses
to follow the
| G/S prior to the PFAF one needs to be mindful that
published and ATC
| assigned altitudes have to be complied with, but that at
SCK that was
| not an issue.
|

[Bob Moore]

"Jim Macklin" >wrote

> If an altitude is underlined, it is the MINIMUM altitude...
> if an altitude is over-lined it is the maximum altitude. If
> it is both under and over-lined the altitude is mandatory.

Jim, you've really got to make a better attempt at keeping up
with these threads.

Garner Miller posted this a few days back:
1800 is the minimum altitude; that's why it's underlined only on the
bottom of the number on the NACO charts. If it were mandatory, it
would have lines above and below (or the word "Mandatory" on Jepp
charts), and you would have to go down to 1800.

Bob Moore

[Jim Macklin]

I would try to monitor these groups 24/7 but sleep and other
tasks get in the way. Some posts get lost, some are
snipped, some don't include any of the previous post, sorry
if I post something that has been covered before.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Bob Moore" > wrote in message
. 122...
| "Jim Macklin" >wrote
|
| > If an altitude is underlined, it is the MINIMUM
altitude...
| > if an altitude is over-lined it is the maximum altitude.
If
| > it is both under and over-lined the altitude is
mandatory.
|
| Jim, you've really got to make a better attempt at keeping
up
| with these threads.
|
| Garner Miller posted this a few days back:
| 1800 is the minimum altitude; that's why it's underlined
only on the
| bottom of the number on the NACO charts. If it were
mandatory, it
| would have lines above and below (or the word "Mandatory"
on Jepp
| charts), and you would have to go down to 1800.
|
| Bob Moore

[John Clonts]

Jim,

In particular Ed is trying to get Tim to explain why Tim thinks it is "technically illegal" to follow a
glideslope down to the glideslope intercept point instead of flying level at the glideslope intercept altitude.
I'm waiting for that explanation as well (though I suspect it was just some "sloppy" phraseology on Tim's
part).

--
Cheers,
John Clonts
Temple, Texas
N7NZ

"Jim Macklin" > wrote in message news:DPUCf.69835$QW2.2295@dukeread08...
>I would try to monitor these groups 24/7 but sleep and other
> tasks get in the way. Some posts get lost, some are
> snipped, some don't include any of the previous post, sorry
> if I post something that has been covered before.
>
>
> --
> James H. Macklin
> ATP,CFI,A&P
>
> --
> The people think the Constitution protects their rights;
> But government sees it as an obstacle to be overcome.
> some support
> http://www.usdoj.gov/olc/secondamendment2.htm
> See http://www.fija.org/ more about your rights and duties.
>
>
> "Bob Moore" > wrote in message
> . 122...
> | "Jim Macklin" >wrote
> |
> | > If an altitude is underlined, it is the MINIMUM
> altitude...
> | > if an altitude is over-lined it is the maximum altitude.
> If
> | > it is both under and over-lined the altitude is
> mandatory.
> |
> | Jim, you've really got to make a better attempt at keeping
> up
> | with these threads.
> |
> | Garner Miller posted this a few days back:
> | 1800 is the minimum altitude; that's why it's underlined
> only on the
> | bottom of the number on the NACO charts. If it were
> mandatory, it
> | would have lines above and below (or the word "Mandatory"
> on Jepp
> | charts), and you would have to go down to 1800.
> |
> | Bob Moore
>
>

[Gene Whitt]

Jerry,
It's been a few years since I flew down to San Jose to watch your first
solo. This thread of some 46 responses made my late arrival all the more
interesting.

There is an interesting side light to the SCK 29 ILS that I learned before I
had my instrument rating which was not required for my CFI back then. I was
flying as safety pilot in VFR as a rated pilot was shooting the ILS to 29
when somewhere about 600' the localizer needel went crazy and all the way to
the right side even though the runway was directly ahead. This was some 30
years ago.

Interesting as to why this might be and happen and I will tell you why but
make your best guess now.

It could be that equipment was not as sensitive as it is today but suggest
those of you who
want to see what happens I suggest that you set the localizer to 110.1
instead of 109.1 and fly the procedure and see how the localizer works, if
at all. Under the right conditions it
should give the same response as I have described. 110.1 happens to the the
Localizer
frequency at one of the two runways (21RL) at Travis AFB.nearly 30 miles
away but in line with Stockton's 29.

When I went on to get my II (double I0 I found that I had learned more about
how instrument mistakes happen flying as safety pilot that when taking
instruction.
Let me know if you give it a try.
Gene Whitt

[Steven P. McNicoll]

> wrote in message
oups.com...
>
> Yesterday I was out getting an IPC. We were doing the Stockton, CA
> ILS. ATC had us intercepting the localizer at 2000 feet. The altitude
> for
> glideslope interception is 1800 ( underlined ).
>
> My old CFII taught me that the glideslope interception altitude on
> the chart is a minimum altitude, and that it was fine to intercept it
> higher. So I just tootled along at 2000 - figuring it was simpler to
> do one configuration change at GS interception rather than three
> changes - one to descend the 200 feet, another to level off, and
> a third to intercept the glideslope.
>
> The new CFII criticized this procedure and told me that the plate
> specified 1800, and it was wrong to intercept at 2000. Which
> one was right?
>

Your old one. Did your new one happen to say why he felt it was wrong?

[Steven P. McNicoll]

"Bob Gardner" > wrote in message
...
>
> FWIW, I have been chewed out by Seattle Approach for intercepting higher
> than the published GSIA of 2200 for the ILS 13R.
>

What was your clearance?

[Steven P. McNicoll]

"Doug" > wrote in message
ups.com...
>
> What did your CFI tell you to do? Decline ATC's instruction? If you do
> that, the ATC guy is going to be confused and probably ask you what it
> is you want to do. In which case you can tell him that you want to go
> down to 1800' and intercept there. Ok, descend to 1800', intercept and
> cleared.
>

That may not be possible. If the MVA is 2000 then 2000 is as low as ATC can
go.

[Steven P. McNicoll]

"Dave Butler" > wrote in message
news:1138302691.662580@sj-nntpcache-5...
>
> OTOH, that got me wondering how much above the published glide slope
> intercept altitude I would accept. To take an extreme example to
> illustrate the question (not a realistic example, of course) suppose ATC
> had you intercepting the localizer at 10000 feet.
>
> For the purposes of the thought experiment, assume this still allows you
> to intercept the glide slope from below. Could you be confident that the
> glide slope had been flight-checked up to 10000 feet? No. You also don't
> know that it's been flight checked to 2000 feet. Where do you draw the
> line?
>

That scenario would have you intercepting the localizer 26 miles or more
from JOTLY. If ATC was to issue an approach clearance at that point they'd
have to issue an altitude to maintain until the aircraft was on a published
segment of the approach. "Cross SIMMS at or above two thousand, cleared ILS
Runway two niner right approach."

[[email protected]]

wrote:
> I agree with everything you just wrote. But, you have not addressed
> my question. In what way does/can following the glideslope from 2000
> to 1800 feet at SCK violate the regulatory implications of the SCK
> ILS's 8260-3?

In the specifics cited for Stockton there is no issue of legality. My
understanding was that the CFII in question was making a general
statement about the limitations of the G/S prior to the PFAF; that is,
it is advisory only. Although using it as advisory at Stockton and
using 1800 as the floor prior to the PFAF would be both legal and
permissiable technique, it will not work where there are intervening
stepdown fixes between the point at which the approach clearance is
received and the PFAF.

It is also permissible technique to disregard the G/S and simply drive
it down to 1,800 to intercept the G/S from below, assuming there is
sufficient distance to do that.

I surmised that the CFI was thinking in global terms, and failed to
provide a complete explanation. Then again, my understanding about what
was (in) the CFI's mind is fragile at best.

In general terms: it is not legal to use the G/S as primary prior to the
PFAF. That is an important concept for the pilot to understand. It has
been proven more than once that a lot of air carrier pilots don't
understand it.

[[email protected]]

"In the specifics cited for Stockton there is no issue of legality."

We're agreed then.

I had attempted to emphasize in my long series of messages to you that
*I* was talking about Stockton, whatever might have been in the CFI's
mind.

Ed

[[email protected]]

Doug wrote:
>
> What did your CFI tell you to do? Decline ATC's instruction?

*** Actually, he didn't tell me to do anything. He mentioned it after
I had already started down the glideslope. At that point, I was pretty
busy, so I just said "Let's talk about it on the ground".

Then on the ground, it slipped through the slats.

- Jerry Kaidor (
)

[[email protected]]

Gene Whitt wrote:
> Jerry,
> It's been a few years since I flew down to San Jose to watch your first
> solo. This thread of some 46 responses made my late arrival all the more
> interesting.
*** Greetings Gene! I still have the photos you took up on my
refrigerator!

>
> There is an interesting side light to the SCK 29 ILS that I learned before I
> had my instrument rating which was not required for my CFI back then. I was
> flying as safety pilot in VFR as a rated pilot was shooting the ILS to 29
> when somewhere about 600' the localizer needel went crazy and all the way to
> the right side even though the runway was directly ahead. This was some 30
> years ago.
>
> Interesting as to why this might be and happen and I will tell you why but
> make your best guess now.
>
> It could be that equipment was not as sensitive as it is today

*** Or it could be that it was more sensitive. I have two NAV
receivers: a
KX170B and a GNS430. The 170B is definitely more sensitive.


but suggest
> those of you who
> want to see what happens I suggest that you set the localizer to 110.1
> instead of 109.1 and fly the procedure and see how the localizer works, if
> at all. Under the right conditions it
> should give the same response as I have described. 110.1 happens to the the
> Localizer
> frequency at one of the two runways (21RL) at Travis AFB.nearly 30 miles
> away but in line with Stockton's 29.

*** The localizer signal is AFAIK produced by two transmitters, both
amplitude
modulated. One has a 90Hz tone, the other one has a 150Hz tone. It
looks
like a sort of positional diversity took place where one of the signals
had an
obstruction way out there in the Valley somewhere.

When I did my Private X-country, I tuned in the wrong VOR and
merrily
navigated on it for about 10 miles. These days, I try to be very
disciplined about
always ID-ing navaids before using them.

- Jerry Kaidor ( )