In this month's AOPA Flight Training magazine, I read an article
which implied there was still some requirement to remain clear of
the ILS critical area even when the tower was closed.

I've been looking through the AIM, and can't find anything like
this. It does say that when the tower is open, it will keep the
area clear when there is an aircraft past the FAF and the weather
is below 800/2.

Is there a rule which states that the ILS critical area must be
kept clear at any time when the tower is not in operation?

Can you please provide a reference?

Thanks,

--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

Mark Hansen > wrote:

> Is there a rule which states that the ILS critical area must be
> kept clear at any time when the tower is not in operation?

Rule or not, if keeping clear of the ILS critical area is very important
when the tower is open, wouldn't you agree that it probably is just as
important when the tower is closed?

--
Peter
























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"Peter R." > wrote:

> Rule or not, if keeping clear of the ILS critical area is very important
> when the tower is open, wouldn't you agree that it probably is just as
> important when the tower is closed?

(sent too fast)

Assuming, of course, that ceilings and/or visibility were low and an
aircraft were on an ILS approach.

--
Peter
























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I don't see what the tower being open or closed has to do with it. They
don't shut down the ILS when the last controller goes home, and a plane in
the restricted area distorting the glideslope signal is not a good thing.

Bob Gardner

"Mark Hansen" > wrote in message
...
> In this month's AOPA Flight Training magazine, I read an article
> which implied there was still some requirement to remain clear of
> the ILS critical area even when the tower was closed.
>
> I've been looking through the AIM, and can't find anything like
> this. It does say that when the tower is open, it will keep the
> area clear when there is an aircraft past the FAF and the weather
> is below 800/2.
>
> Is there a rule which states that the ILS critical area must be
> kept clear at any time when the tower is not in operation?
>
> Can you please provide a reference?
>
> Thanks,
>
> --
> Mark Hansen, PP-ASEL, Instrument Airplane
> Sacramento, CA

On 11/20/2005 12:41 PM, Bob Gardner wrote:

> I don't see what the tower being open or closed has to do with it. They
> don't shut down the ILS when the last controller goes home, and a plane in
> the restricted area distorting the glideslope signal is not a good thing.

Sure. But the tower is the controlling authority which is instructing
planes to hold clear of the ILS critical area.

If the tower is not in operation, who gives the order?

If the pilot on the ground is supposed to know when to hold clear,
how does he know? He may not even know a plane is using the
ILS. And besides, the tower only needs to keep it clear when the
weather is below 800/2, so does this go for the non-towered airport
as well?

Where is this defined?

>
> Bob Gardner
>
> "Mark Hansen" > wrote in message
> ...
>> In this month's AOPA Flight Training magazine, I read an article
>> which implied there was still some requirement to remain clear of
>> the ILS critical area even when the tower was closed.
>>
>> I've been looking through the AIM, and can't find anything like
>> this. It does say that when the tower is open, it will keep the
>> area clear when there is an aircraft past the FAF and the weather
>> is below 800/2.
>>
>> Is there a rule which states that the ILS critical area must be
>> kept clear at any time when the tower is not in operation?
>>
>> Can you please provide a reference?
>>
>> Thanks,
>>
>> --
>> Mark Hansen, PP-ASEL, Instrument Airplane
>> Sacramento, CA
>
>


--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

Mark Hansen > wrote:
> In this month's AOPA Flight Training magazine, I read an article
> which implied there was still some requirement to remain clear of
> the ILS critical area even when the tower was closed.

The reason you're supposed to keep clear of the ILS critical area is
because your airplane can affect the glide slope beam. The presence or
absence of somebody in the tower doesn't change the physics of how
microwaves interact with metallic bodies.

On 11/20/2005 12:55 PM, Roy Smith wrote:

> Mark Hansen > wrote:
>> In this month's AOPA Flight Training magazine, I read an article
>> which implied there was still some requirement to remain clear of
>> the ILS critical area even when the tower was closed.
>
> The reason you're supposed to keep clear of the ILS critical area is
> because your airplane can affect the glide slope beam. The presence or
> absence of somebody in the tower doesn't change the physics of how
> microwaves interact with metallic bodies.

Thanks, but that wasn't my question. In fact, you snipped my question
out of the 'quote' which you included in your response.

--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

"Mark Hansen" > wrote in message
...
>
> Sure. But the tower is the controlling authority which is instructing
> planes to hold clear of the ILS critical area.
>
> If the tower is not in operation, who gives the order?
>

Nobody.


>
> If the pilot on the ground is supposed to know when to hold clear,
> how does he know? He may not even know a plane is using the
> ILS. And besides, the tower only needs to keep it clear when the
> weather is below 800/2, so does this go for the non-towered airport
> as well?
>

Well, if it's only a problem when an aircraft is on the ILS and it's below
800/2, and given that ATC isn't going to release an IFR departure if an
aircraft is on the ILS, then it doesn't appear to be a problem.


>
> Where is this defined?
>

I don't believe it's defined anywhere.

On 11/20/2005 1:25 PM, Steven P. McNicoll wrote:

> "Mark Hansen" > wrote in message
> ...
>>
>> Sure. But the tower is the controlling authority which is instructing
>> planes to hold clear of the ILS critical area.
>>
>> If the tower is not in operation, who gives the order?
>>
>
> Nobody.
>
>
>>
>> If the pilot on the ground is supposed to know when to hold clear,
>> how does he know? He may not even know a plane is using the
>> ILS. And besides, the tower only needs to keep it clear when the
>> weather is below 800/2, so does this go for the non-towered airport
>> as well?
>>
>
> Well, if it's only a problem when an aircraft is on the ILS and it's below
> 800/2, and given that ATC isn't going to release an IFR departure if an
> aircraft is on the ILS, then it doesn't appear to be a problem.

I'm not sure that's the only time it's a problem. It just the minimum
that the tower is required to keep the area clear. I would expect that
ILS can be interfered with regardless of the current weather.

>
>
>>
>> Where is this defined?
>>
>
> I don't believe it's defined anywhere.

Thanks,

--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

Mark Hansen > wrote:

> > Well, if it's only a problem when an aircraft is on the ILS and it's below
> > 800/2, and given that ATC isn't going to release an IFR departure if an
> > aircraft is on the ILS, then it doesn't appear to be a problem.
>
> I'm not sure that's the only time it's a problem. It just the minimum
> that the tower is required to keep the area clear. I would expect that
> ILS can be interfered with regardless of the current weather.

I think the idea is that even a distorted GS will be accurate enough to get
you to within 800/2 of the runway.

"Mark Hansen" > wrote in message
...
>
> I'm not sure that's the only time it's a problem. It just the minimum
> that the tower is required to keep the area clear. I would expect that
> ILS can be interfered with regardless of the current weather.
>

Certainly, but if the weather's good how is that a problem?

It may be the localizer that you are interfering with, not only the GS.



Roy Smith wrote:
> Mark Hansen > wrote:
>
>
>>>Well, if it's only a problem when an aircraft is on the ILS and it's below
>>>800/2, and given that ATC isn't going to release an IFR departure if an
>>>aircraft is on the ILS, then it doesn't appear to be a problem.
>>
>>I'm not sure that's the only time it's a problem. It just the minimum
>>that the tower is required to keep the area clear. I would expect that
>>ILS can be interfered with regardless of the current weather.
>
>
> I think the idea is that even a distorted GS will be accurate enough to get
> you to within 800/2 of the runway.

AIM Figure 2-3-16? If there are taxiway markings for an ILS critical area,
and the departing pilot knows that the weather is even close to 800-2, s/he
doesn't have to depend on a controller for instructions. The controlling
authority (in the absence of a controller) knows what the situation with
regards to inbounds is and can advise the departing pilot if there is
someone on the way in. "Hold short of runway 16, traffic on two mile final."

Bob Gardner

"Mark Hansen" > wrote in message
...
> On 11/20/2005 12:41 PM, Bob Gardner wrote:
>
>> I don't see what the tower being open or closed has to do with it. They
>> don't shut down the ILS when the last controller goes home, and a plane
>> in the restricted area distorting the glideslope signal is not a good
>> thing.
>
> Sure. But the tower is the controlling authority which is instructing
> planes to hold clear of the ILS critical area.
>
> If the tower is not in operation, who gives the order?
>
> If the pilot on the ground is supposed to know when to hold clear,
> how does he know? He may not even know a plane is using the
> ILS. And besides, the tower only needs to keep it clear when the
> weather is below 800/2, so does this go for the non-towered airport
> as well?
>
> Where is this defined?
>
>>
>> Bob Gardner
>>
>> "Mark Hansen" > wrote in message
>> ...
>>> In this month's AOPA Flight Training magazine, I read an article
>>> which implied there was still some requirement to remain clear of
>>> the ILS critical area even when the tower was closed.
>>>
>>> I've been looking through the AIM, and can't find anything like
>>> this. It does say that when the tower is open, it will keep the
>>> area clear when there is an aircraft past the FAF and the weather
>>> is below 800/2.
>>>
>>> Is there a rule which states that the ILS critical area must be
>>> kept clear at any time when the tower is not in operation?
>>>
>>> Can you please provide a reference?
>>>
>>> Thanks,
>>>
>>> --
>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>> Sacramento, CA
>>
>>
>
>
> --
> Mark Hansen, PP-ASEL, Instrument Airplane
> Sacramento, CA

Isn't the localizer antenna down at the other end of the runway? If a pilot
is departing from the end, the localizer signal should be 700 feet wide at
that point.

Bob Gardner


Bob Gardner

"Newps" > wrote in message
. ..
> It may be the localizer that you are interfering with, not only the GS.
>
>
>
> Roy Smith wrote:
>> Mark Hansen > wrote:
>>
>>
>>>>Well, if it's only a problem when an aircraft is on the ILS and it's
>>>>below 800/2, and given that ATC isn't going to release an IFR departure
>>>>if an aircraft is on the ILS, then it doesn't appear to be a problem.
>>>
>>>I'm not sure that's the only time it's a problem. It just the minimum
>>>that the tower is required to keep the area clear. I would expect that
>>>ILS can be interfered with regardless of the current weather.
>>
>>
>> I think the idea is that even a distorted GS will be accurate enough to
>> get you to within 800/2 of the runway.

"Bob Gardner" > wrote in message
...
>
> AIM Figure 2-3-16? If there are taxiway markings for an ILS critical area,
> and the departing pilot knows that the weather is even close to 800-2,
> s/he doesn't have to depend on a controller for instructions. The
> controlling authority (in the absence of a controller) knows what the
> situation with regards to inbounds is and can advise the departing pilot
> if there is someone on the way in. "Hold short of runway 16, traffic on
> two mile final."
>

What is the controlling authority in the absence of a controller?

"Bob Gardner" > wrote in message
...
>
> Isn't the localizer antenna down at the other end of the runway? If a
> pilot is departing from the end, the localizer signal should be 700 feet
> wide at that point.
>

They're at opposite ends of the runway and you're not going to interfere
with both of them simultaneously, but your taxi route may take you through
both of them.

How many fields are there where this is a concern? I would expect most
fields with the congestion to require marked ILS critical areas to have
full-time towers.

In article >,
Roy Smith > wrote:

> Mark Hansen > wrote:
> > In this month's AOPA Flight Training magazine, I read an article
> > which implied there was still some requirement to remain clear of
> > the ILS critical area even when the tower was closed.
>
> The reason you're supposed to keep clear of the ILS critical area is
> because your airplane can affect the glide slope beam. The presence or
> absence of somebody in the tower doesn't change the physics of how
> microwaves interact with metallic bodies.

The glideslope signal is reflected off the ground. The structure that
houses the GS antenna is located far enough down the runway so that the
GS signal is bounced off the ground approximately 1000 feet from the
approach end of the runway. If you look, you will notice the ground is
quite flat and level where the signal is reflected. An object,
especially metal, which intrudes in the space between the antenna and
the runway threshold at the approach end of the runway may distort the
GS signal.

"Mark Hansen" > wrote in message
...
> In this month's AOPA Flight Training magazine, I read an article
> which implied there was still some requirement to remain clear of
> the ILS critical area even when the tower was closed.
>
> I've been looking through the AIM, and can't find anything like
> this. It does say that when the tower is open, it will keep the
> area clear when there is an aircraft past the FAF and the weather
> is below 800/2.
>
> Is there a rule which states that the ILS critical area must be
> kept clear at any time when the tower is not in operation?
>
> Can you please provide a reference?

Maybe no rule but good airmanship should keep you out of the critical area
if its required.

On 11/20/2005 2:54 PM, Bob Gardner wrote:

> AIM Figure 2-3-16?

Sorry I wasn't clear, Bob. I wasn't asking where the hold short
or ILS markings were or how they were depicted at the airport.


> If there are taxiway markings for an ILS critical area,
> and the departing pilot knows that the weather is even close to 800-2, s/he
> doesn't have to depend on a controller for instructions. The controlling
> authority (in the absence of a controller) knows what the situation with
> regards to inbounds is and can advise the departing pilot if there is
> someone on the way in. "Hold short of runway 16, traffic on two mile final."

Just who is going to say "Hold short" when the tower is closed?

Perhaps the only time you have to worry about the ILS critical area
is when the weather is below 800/2, in which case only IFR departures
will be of concern, and they won't get their clearance unless the
airspace is clear.

Assuming the weather is above VFR minimums, VFR arrivals and departures
could interfere with the ILS system, and there appears to be no protocol
to prevent that, since any airplane using the system isn't depending on it
to get to minimums anyway?

Well, I guess I have my answer.

>
> Bob Gardner
>
> "Mark Hansen" > wrote in message
> ...
>> On 11/20/2005 12:41 PM, Bob Gardner wrote:
>>
>>> I don't see what the tower being open or closed has to do with it. They
>>> don't shut down the ILS when the last controller goes home, and a plane
>>> in the restricted area distorting the glideslope signal is not a good
>>> thing.
>>
>> Sure. But the tower is the controlling authority which is instructing
>> planes to hold clear of the ILS critical area.
>>
>> If the tower is not in operation, who gives the order?
>>
>> If the pilot on the ground is supposed to know when to hold clear,
>> how does he know? He may not even know a plane is using the
>> ILS. And besides, the tower only needs to keep it clear when the
>> weather is below 800/2, so does this go for the non-towered airport
>> as well?
>>
>> Where is this defined?
>>
>>>
>>> Bob Gardner
>>>
>>> "Mark Hansen" > wrote in message
>>> ...
>>>> In this month's AOPA Flight Training magazine, I read an article
>>>> which implied there was still some requirement to remain clear of
>>>> the ILS critical area even when the tower was closed.
>>>>
>>>> I've been looking through the AIM, and can't find anything like
>>>> this. It does say that when the tower is open, it will keep the
>>>> area clear when there is an aircraft past the FAF and the weather
>>>> is below 800/2.
>>>>
>>>> Is there a rule which states that the ILS critical area must be
>>>> kept clear at any time when the tower is not in operation?
>>>>
>>>> Can you please provide a reference?
>>>>
>>>> Thanks,
>>>>
>>>> --
>>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>>> Sacramento, CA
>>>
>>>
>>
>>
>> --
>> Mark Hansen, PP-ASEL, Instrument Airplane
>> Sacramento, CA
>
>


--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

On 11/20/2005 3:56 PM, Chris wrote:

> "Mark Hansen" > wrote in message
> ...
>> In this month's AOPA Flight Training magazine, I read an article
>> which implied there was still some requirement to remain clear of
>> the ILS critical area even when the tower was closed.
>>
>> I've been looking through the AIM, and can't find anything like
>> this. It does say that when the tower is open, it will keep the
>> area clear when there is an aircraft past the FAF and the weather
>> is below 800/2.
>>
>> Is there a rule which states that the ILS critical area must be
>> kept clear at any time when the tower is not in operation?
>>
>> Can you please provide a reference?
>
> Maybe no rule but good airmanship should keep you out of the critical area
> if its required.
>
>

How does the pilot know it is required if not told to keep clear of
the area by the control tower?

--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

Bob Gardner wrote:
> Isn't the localizer antenna down at the other end of the runway? If a pilot
> is departing from the end, the localizer signal should be 700 feet wide at
> that point.

I've had discussions with the FAA's flight check pilots as they are out
flying approaches checking our navaids. The critical area can be for
both the GS and Loc. Their equipment is so good in the flight check
aircraft they can tell if a person walks across the middle of the runway
from a 10 mile final.

"Mark Hansen" > wrote in message
...
>
> How does the pilot know it is required if not told to keep clear of
> the area by the control tower?
>

He can't know for sure when it is required. But if he's issued an IFR
departure clearance and not told to hold for release he knows it's not
required and without an IFR departure clearance there's little reason to
enter the critical area.

On Sun, 20 Nov 2005 11:28:09 -0800, Mark Hansen >
wrote:

>In this month's AOPA Flight Training magazine, I read an article
>which implied there was still some requirement to remain clear of
>the ILS critical area even when the tower was closed.
>
>I've been looking through the AIM, and can't find anything like
>this. It does say that when the tower is open, it will keep the
>area clear when there is an aircraft past the FAF and the weather
>is below 800/2.
>
>Is there a rule which states that the ILS critical area must be
>kept clear at any time when the tower is not in operation?
>
>Can you please provide a reference?
>
>Thanks,


All I can find is a statement in the AIM that the ILS critical area is NOT
protected at uncontrolled fields; so y'all be careful out there!


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

Ron Rosenfeld wrote:
> On Sun, 20 Nov 2005 11:28:09 -0800, Mark Hansen >
> wrote:
>
>
>>In this month's AOPA Flight Training magazine, I read an article
>>which implied there was still some requirement to remain clear of
>>the ILS critical area even when the tower was closed.
>>
>>I've been looking through the AIM, and can't find anything like
>>this. It does say that when the tower is open, it will keep the
>>area clear when there is an aircraft past the FAF and the weather
>>is below 800/2.
>>
>>Is there a rule which states that the ILS critical area must be
>>kept clear at any time when the tower is not in operation?
>>
>>Can you please provide a reference?
>>
>>Thanks,
>
>
>
> All I can find is a statement in the AIM that the ILS critical area is NOT
> protected at uncontrolled fields; so y'all be careful out there!
>
>
> Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)
At many airports, such as my home field, KRYY, the glideslope is "unusable" when the
tower is closed... Perhaps that is some additional 'protection'....

"Mike H" > wrote in message
. ..
>
> At many airports, such as my home field, KRYY, the glideslope is
> "unusable" when the tower is closed... Perhaps that is some additional
> 'protection'....
>

At many airports? I can't think of any other. Any idea why the GS is
unusable when the tower is closed?

On Mon, 21 Nov 2005 01:31:40 GMT, Steven P. McNicoll wrote:

> "Mike H" > wrote in message
> . ..
>>
>> At many airports, such as my home field, KRYY, the glideslope is
>> "unusable" when the tower is closed... Perhaps that is some additional
>> 'protection'....
>>
>
> At many airports? I can't think of any other. Any idea why the GS is
> unusable when the tower is closed?

Steve,

I've seen it myself. One that comes to mind is HKS.

On the approach plate, says when tower closed, GS unusable.

Delta airspace that underlies JAN Charlie airspace....

Allen

Good point about the 'hold short' transmission. Brain fart.

Seems to me that at one point you wondered how a pilot was expected to know
that there was an ILS critical area without being told by the tower...that
is why I referred to the taxiway markings.

Bob

"Mark Hansen" > wrote in message
...
> On 11/20/2005 2:54 PM, Bob Gardner wrote:
>
>> AIM Figure 2-3-16?
>
> Sorry I wasn't clear, Bob. I wasn't asking where the hold short
> or ILS markings were or how they were depicted at the airport.
>
>
> > If there are taxiway markings for an ILS critical
> > area,
>> and the departing pilot knows that the weather is even close to 800-2,
>> s/he doesn't have to depend on a controller for instructions. The
>> controlling authority (in the absence of a controller) knows what the
>> situation with regards to inbounds is and can advise the departing pilot
>> if there is someone on the way in. "Hold short of runway 16, traffic on
>> two mile final."
>
> Just who is going to say "Hold short" when the tower is closed?
>
> Perhaps the only time you have to worry about the ILS critical area
> is when the weather is below 800/2, in which case only IFR departures
> will be of concern, and they won't get their clearance unless the
> airspace is clear.
>
> Assuming the weather is above VFR minimums, VFR arrivals and departures
> could interfere with the ILS system, and there appears to be no protocol
> to prevent that, since any airplane using the system isn't depending on it
> to get to minimums anyway?
>
> Well, I guess I have my answer.
>
>>
>> Bob Gardner
>>
>> "Mark Hansen" > wrote in message
>> ...
>>> On 11/20/2005 12:41 PM, Bob Gardner wrote:
>>>
>>>> I don't see what the tower being open or closed has to do with it. They
>>>> don't shut down the ILS when the last controller goes home, and a plane
>>>> in the restricted area distorting the glideslope signal is not a good
>>>> thing.
>>>
>>> Sure. But the tower is the controlling authority which is instructing
>>> planes to hold clear of the ILS critical area.
>>>
>>> If the tower is not in operation, who gives the order?
>>>
>>> If the pilot on the ground is supposed to know when to hold clear,
>>> how does he know? He may not even know a plane is using the
>>> ILS. And besides, the tower only needs to keep it clear when the
>>> weather is below 800/2, so does this go for the non-towered airport
>>> as well?
>>>
>>> Where is this defined?
>>>
>>>>
>>>> Bob Gardner
>>>>
>>>> "Mark Hansen" > wrote in message
>>>> ...
>>>>> In this month's AOPA Flight Training magazine, I read an article
>>>>> which implied there was still some requirement to remain clear of
>>>>> the ILS critical area even when the tower was closed.
>>>>>
>>>>> I've been looking through the AIM, and can't find anything like
>>>>> this. It does say that when the tower is open, it will keep the
>>>>> area clear when there is an aircraft past the FAF and the weather
>>>>> is below 800/2.
>>>>>
>>>>> Is there a rule which states that the ILS critical area must be
>>>>> kept clear at any time when the tower is not in operation?
>>>>>
>>>>> Can you please provide a reference?
>>>>>
>>>>> Thanks,
>>>>>
>>>>> --
>>>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>>>> Sacramento, CA
>>>>
>>>>
>>>
>>>
>>> --
>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>> Sacramento, CA
>>
>>
>
>
> --
> Mark Hansen, PP-ASEL, Instrument Airplane
> Sacramento, CA

Golly, Steve, unless it is a departure from a Class G airport with
controlled airspace at 700 feet, the surface area must belong to someone,
right? Class E down to the ground? Whatever facility has made a slot into
which a valid time departure will fit?

Bob Gardner

"Steven P. McNicoll" > wrote in message
k.net...
>
> "Bob Gardner" > wrote in message
> ...
>>
>> AIM Figure 2-3-16? If there are taxiway markings for an ILS critical
>> area, and the departing pilot knows that the weather is even close to
>> 800-2, s/he doesn't have to depend on a controller for instructions. The
>> controlling authority (in the absence of a controller) knows what the
>> situation with regards to inbounds is and can advise the departing pilot
>> if there is someone on the way in. "Hold short of runway 16, traffic on
>> two mile final."
>>
>
> What is the controlling authority in the absence of a controller?
>

Mark Hansen wrote:


>
> Where is this defined?

It's defined by the sign and some common sense.

The folks who establish these standards can't have FAA legal write rules
for everything.

Mark Hansen > wrote:

> How does the pilot know it is required if not told to keep clear of
> the area by the control tower?

By knowing the weather, knowing that someone is on the approach, and
knowing where the ILS critical area is.

--
Peter
























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Steven P. McNicoll wrote:

> "Bob Gardner" > wrote in message
> ...

>
> How many fields are there where this is a concern? I would expect most
> fields with the congestion to require marked ILS critical areas to have
> full-time towers.
>
>
I can't provide a cite, but I was told recently that there are ILS
critical areas at part-time towered airports.

Steven P. McNicoll wrote:

> "Mark Hansen" > wrote in message
> ...
>
>>I'm not sure that's the only time it's a problem. It just the minimum
>>that the tower is required to keep the area clear. I would expect that
>>ILS can be interfered with regardless of the current weather.
>>
>
>
> Certainly, but if the weather's good how is that a problem?
>
It's a problem during a coupled approach especially if the pilot is
planning to do an autoland.

> wrote:

> I can't provide a cite, but I was told recently that there are ILS
> critical areas at part-time towered airports.

Schenectady County Airport, KSCH, is a part time towered airport with an
ILS critical area.

--
Peter
























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On Sun, 20 Nov 2005 20:17:55 -0500, Mike H > wrote:

>
>
>Ron Rosenfeld wrote:
>> On Sun, 20 Nov 2005 11:28:09 -0800, Mark Hansen >
>> wrote:
>>
>>
>>>In this month's AOPA Flight Training magazine, I read an article
>>>which implied there was still some requirement to remain clear of
>>>the ILS critical area even when the tower was closed.
>>>
>>>I've been looking through the AIM, and can't find anything like
>>>this. It does say that when the tower is open, it will keep the
>>>area clear when there is an aircraft past the FAF and the weather
>>>is below 800/2.
>>>
>>>Is there a rule which states that the ILS critical area must be
>>>kept clear at any time when the tower is not in operation?
>>>
>>>Can you please provide a reference?
>>>
>>>Thanks,
>>
>>
>>
>> All I can find is a statement in the AIM that the ILS critical area is NOT
>> protected at uncontrolled fields; so y'all be careful out there!
>>
>>
>> Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)
>At many airports, such as my home field, KRYY, the glideslope is "unusable" when the
>tower is closed... Perhaps that is some additional 'protection'....


What other airports are like that?

I've not flown into any fields where the GS is "unusable" when the tower is
closed, and there are certainly many fields with ILS's and no towers at
all.

Does RYY even have an ILS critical area? I can't tell from my charts.

There's no ILS Hold line marked on the airport diagram.


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

On Sun, 20 Nov 2005 19:51:09 -0600, A Lieberman >
wrote:

>On Mon, 21 Nov 2005 01:31:40 GMT, Steven P. McNicoll wrote:
>
>> "Mike H" > wrote in message
>> . ..
>>>
>>> At many airports, such as my home field, KRYY, the glideslope is
>>> "unusable" when the tower is closed... Perhaps that is some additional
>>> 'protection'....
>>>
>>
>> At many airports? I can't think of any other. Any idea why the GS is
>> unusable when the tower is closed?
>
>Steve,
>
>I've seen it myself. One that comes to mind is HKS.
>
>On the approach plate, says when tower closed, GS unusable.

Does HKS have an ILS critical area?

I don't see an ILS hold line on my charts.

Don't forget, the premise of this particular sub-thread is that making the
GS unusable when the tower is closed is a method of protecting the ILS
critical area. But if the GS is unusable for some other reason, then ...

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

In article <yW9gf.1260$pF.1150@fed1read04>, wrote:

> Steven P. McNicoll wrote:
>
> > "Bob Gardner" > wrote in message
> > ...
>
> >
> > How many fields are there where this is a concern? I would expect most
> > fields with the congestion to require marked ILS critical areas to have
> > full-time towers.
> >
> >
> I can't provide a cite, but I was told recently that there are ILS
> critical areas at part-time towered airports.

HPN has one. Two actually, one at each end.

I did a quick survey (via the airport diagrams available on airnav) of
part-time towers I know around here that have ILS's. None of OCX, FRG,
ISP, MMU, POU, BDR, and HVN appear to have ILS critical areas (at least
none that are charted on the airport diagram), but HPN does.

Interestingly enough, at both ends of the runway at HPN, the ILS Hold Short
lines are only on the taxiways on the left side (as viewed from the
approach) of the runway, which is the side the GS antenna is on in both
cases.

> the weather is below 800/2, in which case only IFR departures
> will be of concern

People may be taxiing around the airport with no intention of taking
off, for example, to fuel up, to do maintanance, or to more the aircraft.

I suppose such an aircraft could call departure first, to ensure that
such operation will not interfere with anybody on approach.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

"Bob Gardner" > wrote in message
. ..
>
> Golly, Steve, unless it is a departure from a Class G airport with
> controlled airspace at 700 feet, the surface area must belong to someone,
> right? Class E down to the ground? Whatever facility has made a slot into
> which a valid time departure will fit?
>

Sure, there could be a Class E surface area, but the overlying TRACON or
ARTCC that owns that airspace has no authority over the runways.

"A Lieberman" > wrote in message
...
>
> I've seen it myself. One that comes to mind is HKS.
>
> On the approach plate, says when tower closed, GS unusable.
>
> Delta airspace that underlies JAN Charlie airspace....
>

I didn't say they didn't exist, I just said I was not aware of any. So I
think he's overstating it a bit when he says the glideslope is unusable when
the tower is closed at many airports.

"Roy Smith" > wrote in message
...
>
> Interestingly enough, at both ends of the runway at HPN, the ILS Hold
> Short
> lines are only on the taxiways on the left side (as viewed from the
> approach) of the runway, which is the side the GS antenna is on in both
> cases.
>

If there was no access to the side on which the GS is sited there'd be no
need to protect the GS critical area.

> wrote in message news:CX9gf.1261$pF.1153@fed1read04...
>
> It's a problem during a coupled approach especially if the pilot is
> planning to do an autoland.
>

It's not a problem if the weather is good.

"Jose" > wrote in message
. ..
>
> People may be taxiing around the airport with no intention of taking off,
> for example, to fuel up, to do maintanance, or to more the aircraft.
>

With all that activity it's a wonder the tower is closed.

On Sun, 20 Nov 2005 21:36:38 -0500, Ron Rosenfeld wrote:

> Does HKS have an ILS critical area?
>
> I don't see an ILS hold line on my charts.

Ron,

You had me pull out my NACO charts. I can't say about HKS as I am not
intimately familiar with their airport, but I know KJAN has an critical ILS
hold short line, but I don't see it depicted on the chart.

Nor do I see any symbols on the airport diagram / airport sketch legend on
page K1 of the MS / LA terminal procedures.

Does NACO depict ILS hold lines on the airport diagrams would be my
question.

> Don't forget, the premise of this particular sub-thread is that making the
> GS unusable when the tower is closed is a method of protecting the ILS
> critical area. But if the GS is unusable for some other reason, then ...

Of course the chart doesn't say why the GS is unusable, just that it is
WHEN tower is closed.

Allen

"A Lieberman" > wrote in message
...
>
> I've seen it myself. One that comes to mind is HKS.
>
> On the approach plate, says when tower closed, GS unusable.
>

Any idea why the GS is unusable when the tower is closed? I'd expect to
find the GS on the east side of the runway, is that where it is?

On 11/20/2005 5:51 PM, Bob Gardner wrote:

> Good point about the 'hold short' transmission. Brain fart.
>
> Seems to me that at one point you wondered how a pilot was expected to know
> that there was an ILS critical area without being told by the tower...that
> is why I referred to the taxiway markings.

No, I was asking how the pilot would know to hold clear of the ILS
critical area, not where it was located on the airport.

But anyway, I think I have my answer. Thanks for your help.

>
> Bob
>
> "Mark Hansen" > wrote in message
> ...
>> On 11/20/2005 2:54 PM, Bob Gardner wrote:
>>
>>> AIM Figure 2-3-16?
>>
>> Sorry I wasn't clear, Bob. I wasn't asking where the hold short
>> or ILS markings were or how they were depicted at the airport.
>>
>>
>> > If there are taxiway markings for an ILS critical
>> > area,
>>> and the departing pilot knows that the weather is even close to 800-2,
>>> s/he doesn't have to depend on a controller for instructions. The
>>> controlling authority (in the absence of a controller) knows what the
>>> situation with regards to inbounds is and can advise the departing pilot
>>> if there is someone on the way in. "Hold short of runway 16, traffic on
>>> two mile final."
>>
>> Just who is going to say "Hold short" when the tower is closed?
>>
>> Perhaps the only time you have to worry about the ILS critical area
>> is when the weather is below 800/2, in which case only IFR departures
>> will be of concern, and they won't get their clearance unless the
>> airspace is clear.
>>
>> Assuming the weather is above VFR minimums, VFR arrivals and departures
>> could interfere with the ILS system, and there appears to be no protocol
>> to prevent that, since any airplane using the system isn't depending on it
>> to get to minimums anyway?
>>
>> Well, I guess I have my answer.
>>
>>>
>>> Bob Gardner
>>>
>>> "Mark Hansen" > wrote in message
>>> ...
>>>> On 11/20/2005 12:41 PM, Bob Gardner wrote:
>>>>
>>>>> I don't see what the tower being open or closed has to do with it. They
>>>>> don't shut down the ILS when the last controller goes home, and a plane
>>>>> in the restricted area distorting the glideslope signal is not a good
>>>>> thing.
>>>>
>>>> Sure. But the tower is the controlling authority which is instructing
>>>> planes to hold clear of the ILS critical area.
>>>>
>>>> If the tower is not in operation, who gives the order?
>>>>
>>>> If the pilot on the ground is supposed to know when to hold clear,
>>>> how does he know? He may not even know a plane is using the
>>>> ILS. And besides, the tower only needs to keep it clear when the
>>>> weather is below 800/2, so does this go for the non-towered airport
>>>> as well?
>>>>
>>>> Where is this defined?
>>>>
>>>>>
>>>>> Bob Gardner
>>>>>
>>>>> "Mark Hansen" > wrote in message
>>>>> ...
>>>>>> In this month's AOPA Flight Training magazine, I read an article
>>>>>> which implied there was still some requirement to remain clear of
>>>>>> the ILS critical area even when the tower was closed.
>>>>>>
>>>>>> I've been looking through the AIM, and can't find anything like
>>>>>> this. It does say that when the tower is open, it will keep the
>>>>>> area clear when there is an aircraft past the FAF and the weather
>>>>>> is below 800/2.
>>>>>>
>>>>>> Is there a rule which states that the ILS critical area must be
>>>>>> kept clear at any time when the tower is not in operation?
>>>>>>
>>>>>> Can you please provide a reference?
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>> --
>>>>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>>>>> Sacramento, CA
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Mark Hansen, PP-ASEL, Instrument Airplane
>>>> Sacramento, CA
>>>
>>>
>>
>>
>> --
>> Mark Hansen, PP-ASEL, Instrument Airplane
>> Sacramento, CA
>
>


--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

On 11/20/2005 6:38 PM, Jose wrote:

>> the weather is below 800/2, in which case only IFR departures
>> will be of concern
>
> People may be taxiing around the airport with no intention of taking
> off, for example, to fuel up, to do maintanance, or to more the aircraft.
>
> I suppose such an aircraft could call departure first, to ensure that
> such operation will not interfere with anybody on approach.
>
> Jose

With weather below 800/2, the only people in the vicinity of the
ILS critical area would be IFR departures, right? I can't think
of any reason to be taxiing to the departure end of a runway unless
you're taking off (or just landed). In either case, the flight would
be IFR due to the weather.

I was really thinking more of the case during VFR conditions where
the ILS system is being used more for practice. I think the bottom
line is, if you're using an ILS during VFR conditions, you should
expect some interference in the signal whether or not the tower is
in operation - since even if it is in operation, it doesn't have to
keep the ILS critical area clear unless weather is below 800/2.

Thanks,


--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

On 11/20/2005 6:02 PM, wrote:

> Mark Hansen wrote:
>
>
>>
>> Where is this defined?
>
> It's defined by the sign and some common sense.

Which common sense is that, Tim? How would a VFR departure know
that there might be another airplane on a 10 mile final using the ILS
system at a non-towered field?

I think that if there is no tower to instruct the pilot to hold
clear of the ILS critical area, there is no need for the pilot to
hold clear. If there was, I would expect there to be a FAR which
states this.

>
> The folks who establish these standards can't have FAA legal write rules
> for everything.


--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA

"Mark Hansen" > wrote in message
...
>
> How would a VFR departure know
> that there might be another airplane on a 10 mile final using the ILS
> system at a non-towered field?
>

By monitoring CTAF? But what is the problem here for a VFR departure?

Steven P. McNicoll wrote:
> "A Lieberman" > wrote in message
> ...
>
>>I've seen it myself. One that comes to mind is HKS.
>>
>>On the approach plate, says when tower closed, GS unusable.
>>
>
>
> Any idea why the GS is unusable when the tower is closed? I'd expect to
> find the GS on the east side of the runway, is that where it is?
>
>

I believe ELM switches the ILS from 6 to 24 depending on the wind
direction. I've never landed after midnight when the tower closes, but
I wonder if they leave the ILS on and leave an ATIS message as to which
runway is ILS active? Never thought about it before this thread. I
guess I always assumed they would turn off the approach when the
controllers go home, but maybe not.


Matt

Matt Whiting > wrote:
> I believe ELM switches the ILS from 6 to 24 depending on the wind
> direction. I've never landed after midnight when the tower closes, but
> I wonder if they leave the ILS on and leave an ATIS message as to which
> runway is ILS active?

That's exactly what they do at HPN.

>> People may be taxiing around the airport with no intention of taking off,
>> for example, to fuel up, to do maintanance, or to more the aircraft.
> With all that activity it's a wonder the tower is closed.
>
One aircraft is sufficient.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

> With weather below 800/2, the only people in the vicinity of the
> ILS critical area would be IFR departures, right?

I don't know. Therefore I wouldn't count on it. I suspect it depends
on the specific geography of the airport.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

"Matt Whiting" > wrote in message
...
>
> I believe ELM switches the ILS from 6 to 24 depending on the wind
> direction.
>

Both localizers are on 109.1, only one can be selected at any time.


>
> I've never landed after midnight when the tower closes, but I wonder if
> they leave the ILS on and leave an ATIS message as to which runway is ILS
> active?

Possibly, but all they'd have to do is advise New York Center which ILS is
up.


>
> Never thought about it before this thread. I guess I always assumed they
> would turn off the approach when the controllers go home, but maybe not.
>

These things are turned off for maintenance or runway closures, that's
pretty much it.

"Jose" > wrote in message
. ..
>
> One aircraft is sufficient.
>

It's typically not enough to keep the fuel vendor open.

In article >,
Jose > wrote:

> >> People may be taxiing around the airport with no intention of taking off,
> >> for example, to fuel up, to do maintanance, or to more the aircraft.
> > With all that activity it's a wonder the tower is closed.
> >
> One aircraft is sufficient.
>
> Jose

Doesn't even have to be an aircraft. A car or truck would disrupt the
signal too. Some uncontrolled airports have some pretty strange stuff
going on.

On Sun, 20 Nov 2005 21:13:54 -0600, A Lieberman >
wrote:

>On Sun, 20 Nov 2005 21:36:38 -0500, Ron Rosenfeld wrote:
>
>> Does HKS have an ILS critical area?
>>
>> I don't see an ILS hold line on my charts.
>
>Ron,
>
>You had me pull out my NACO charts. I can't say about HKS as I am not
>intimately familiar with their airport, but I know KJAN has an critical ILS
>hold short line, but I don't see it depicted on the chart.
>
>Nor do I see any symbols on the airport diagram / airport sketch legend on
>page K1 of the MS / LA terminal procedures.
>
>Does NACO depict ILS hold lines on the airport diagrams would be my
>question.
>
>> Don't forget, the premise of this particular sub-thread is that making the
>> GS unusable when the tower is closed is a method of protecting the ILS
>> critical area. But if the GS is unusable for some other reason, then ...
>
>Of course the chart doesn't say why the GS is unusable, just that it is
>WHEN tower is closed.
>
>Allen

Both Jepp and NACO depict something they call ILS Hold Lines at some
airports. Jepp does not define anything on their airport view with the
term "ILS Critical Area" so I don't know if these ILS hold lines have
anything to do with the ILS Critical area.


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

"Jose" > wrote in message
. ..
>
> Sure it is. The fuel vendor is a machine. It doesn't sleep, and never
> leaves the airport.
>

The fuel vendor is typically a person.

> The fuel vendor is typically a person.

The fuel vendor is typically a machine.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

Up until 2 months ago, there was an ILS critical area at an untowered
field.. KGLS Galveston, TX, and it had been there since i started flying
in 2000.

Galveston now has a part time tower.

Dave



wrote:
> Steven P. McNicoll wrote:
>
>> "Bob Gardner" > wrote in message
>> ...
>
>
>>
>> How many fields are there where this is a concern? I would expect
>> most fields with the congestion to require marked ILS critical areas
>> to have full-time towers.
>>
> I can't provide a cite, but I was told recently that there are ILS
> critical areas at part-time towered airports.

Steven P. McNicoll wrote:
> > wrote in message news:CX9gf.1261$pF.1153@fed1read04...
>
>>It's a problem during a coupled approach especially if the pilot is
>>planning to do an autoland.
>>
>
>
> It's not a problem if the weather is good.
>
>
Not so, Steve. It can cause control problems and certainly adversely
affect an autoland. That is why your handbook contains a caveat about
such approaches.

Approach couplers and autoland systems are weather independent.~

Mark Hansen wrote:

> On 11/20/2005 6:02 PM, wrote:
>
>> Mark Hansen wrote:
>>
>>
>>>
>>> Where is this defined?
>>
>>
>> It's defined by the sign and some common sense.
>
>
> Which common sense is that, Tim? How would a VFR departure know
> that there might be another airplane on a 10 mile final using the ILS
> system at a non-towered field?
>
A tower won't instruct you to hold short of the ILS critical areas with
an aircraft on a 10 mile final.

If you can see an aircraft on approach (or hopefully are clued in by his
CTAF reports) if he is close enough that you decide you need to hold
short, then the common sense decision would be to hold short of the ILS
critical area signs.

It's the conservative and safest option. And, it's what the FAA airport
folks hope you will do.

A Lieberman wrote:

> Does NACO depict ILS hold lines on the airport diagrams would be my
> question.

Another example where it's not charted on the airport diagram: Roanoke, VA has a
critical area marked with signage and pavement marking on taxiway Echo, but it's
not on the airport diagram (http://204.108.4.16/d-tpp/0511/00349AD.PDF).

The approach to that runway (http://204.108.4.16/d-tpp/0511/00349LDA6.PDF)is an
LDA with glide slope and the localizer is not aligned with the runway. I'm not
sure where the localizer/glide slope antenna is, but from the diagram it must be
located somewhere on the non-runway side of taxiway Echo.

Dave

Limitations on the approach chart probably do not allow the
ILS when the tower is closed or more than one hour after the
last weather observation.



> wrote in message
news:cjlgf.4216$pF.687@fed1read04...
| Steven P. McNicoll wrote:
| > > wrote in message
news:CX9gf.1261$pF.1153@fed1read04...
| >
| >>It's a problem during a coupled approach especially if
the pilot is
| >>planning to do an autoland.
| >>
| >
| >
| > It's not a problem if the weather is good.
| >
| >
| Not so, Steve. It can cause control problems and
certainly adversely
| affect an autoland. That is why your handbook contains a
caveat about
| such approaches.
|
| Approach couplers and autoland systems are weather
independent.~

> wrote in message news:cjlgf.4216$pF.687@fed1read04...
>
> Not so, Steve. It can cause control problems and certainly adversely
> affect an autoland. That is why your handbook contains a caveat about
> such approaches.
>
> Approach couplers and autoland systems are weather independent.~
>

You're mistaken. There's no need for approach couplers and autoland systems
when the weather is good. It's not a problem because the pilots can see.

"Dave Butler" > wrote in message news:1132587647.916146@sj-nntpcache->
>
> Another example where it's not charted on the airport diagram: Roanoke, VA
> has a critical area marked with signage and pavement marking on taxiway
> Echo, but it's not on the airport diagram
> (http://204.108.4.16/d-tpp/0511/00349AD.PDF).
>
> The approach to that runway
> (http://204.108.4.16/d-tpp/0511/00349LDA6.PDF)is an LDA with glide slope
> and the localizer is not aligned with the runway. I'm not sure where the
> localizer/glide slope antenna is, but from the diagram it must be located
> somewhere on the non-runway side of taxiway Echo.
>

The LOC/DME is depicted on the LDA RWY 6 approach plate. It's southwest of
the runway 15/33 intersection with taxiway E.

"Jim Macklin" > wrote in message
news:g0mgf.4463$QW2.2168@dukeread08...
>
> Limitations on the approach chart probably do not allow the
> ILS when the tower is closed or more than one hour after the
> last weather observation.
>

What airport are you referring to?

Steven P. McNicoll wrote:
> "Dave Butler" > wrote in message news:1132587647.916146@sj-nntpcache->
>
>>Another example where it's not charted on the airport diagram: Roanoke, VA
>>has a critical area marked with signage and pavement marking on taxiway
>>Echo, but it's not on the airport diagram
>>(http://204.108.4.16/d-tpp/0511/00349AD.PDF).
>>
>>The approach to that runway
>>(http://204.108.4.16/d-tpp/0511/00349LDA6.PDF)is an LDA with glide slope
>>and the localizer is not aligned with the runway. I'm not sure where the
>>localizer/glide slope antenna is, but from the diagram it must be located
>>somewhere on the non-runway side of taxiway Echo.
>>
>
>
> The LOC/DME is depicted on the LDA RWY 6 approach plate. It's southwest of
> the runway 15/33 intersection with taxiway E.

So it is. Thanks. It looks like the area where the glide slope would be bounced
off the ground is right about where taxiway E lies.

Man, I hate to side with McNicholl but...

> wrote in message news:cjlgf.4216$pF.687@fed1read04...
> Steven P. McNicoll wrote:
>> > wrote in message news:CX9gf.1261$pF.1153@fed1read04...
>>
>>>It's a problem during a coupled approach especially if the pilot is
>>>planning to do an autoland.
>>>
>>
>>
>> It's not a problem if the weather is good.
>>
>>
> Not so, Steve. It can cause control problems and certainly adversely
> affect an autoland. That is why your handbook contains a caveat about
> such approaches.
>
> Approach couplers and autoland systems are weather independent.~

The only "caveat" in the .65 regarding coupled or autoland ILS approaches is
in 3-7-5b. This simply requires an advisory to aircraft of "ILS/MLS
CRITICAL AREA NOT PROTECTED" when the weather is at or above 800-2.

So, if the weather is good (or good enough) all the pilot executing a
coupled or autoland gets is a warning (ie, a reminder not to trust the
electrons too much). For all practical purposes the ILS critical areas are
not in play. Nobody gets held at the instrument hold lines. In other
words, it's not a problem if the weather is good.

As for the original question of the critical areas when the tower is closed,
I'm not sure it's really that big of a problem.

-The actual critical areas aren't really that big. The chances of them
overlapping onto non-movement parking or refueling areas doesn't seem too
likely to me (could be wrong though)
-A flight check may have verified that the critical area isn't really all
that critical at that particular airport
-Airport management can put signs at the instrument hold line(s) "Do not
proceed past this point when the weather is below 800-2 and the tower is
closed "
-The ILS can be published as unusable when the tower is closed
-Aircraft on the ILS during those times and in that weather are in the "You
pays your money and you takes your chance" category

Steven P. McNicoll wrote:
> > wrote in message news:cjlgf.4216$pF.687@fed1read04...
> You're mistaken. There's no need for approach couplers and autoland systems
> when the weather is good. It's not a problem because the pilots can see.

wrong. There might be "need" to do autolanding for 3 month (?)
currency. I hear this often at night for jets going into SFO.
Granted the pilots turn off the autopilot with no loss of
safety but the need is still there.

Gerald

"Gerald Sylvester" > wrote in message
m...
>
> wrong. There might be "need" to do autolanding for 3 month (?)
> currency.

It's not a problem because the pilots can see. The need for currency
doesn't alter the weather.


>
> I hear this often at night for jets going into SFO.
>

SFO has a full-time tower.

Steven P. McNicoll wrote:
> > wrote in message news:cjlgf.4216$pF.687@fed1read04...
>
>>Not so, Steve. It can cause control problems and certainly adversely
>>affect an autoland. That is why your handbook contains a caveat about
>>such approaches.
>>
>>Approach couplers and autoland systems are weather independent.~
>>
>
>
> You're mistaken. There's no need for approach couplers and autoland systems
> when the weather is good. It's not a problem because the pilots can see.
>
>
Well, okay, Steve. When I flew that equipment we often did autolands in
good weather as part of the continuing certification of the system for
CAT III operations. And, an air carrier flight could be going into a
non-towered airport using the ILS when the weather is "iffy" VFR.

The "need" to use couplers and perhaps autoland systems is determined by
the carrier and it POI.

wrote:

When I flew that equipment we often did autolands in
> good weather as part of the continuing certification of the system for
> CAT III operations. And, an air carrier flight could be going into a
> non-towered airport using the ILS when the weather is "iffy" VFR.

The airlines will always fly the ILS if there is one up and running.
They are required to.

> wrote in message news:3Bpgf.4263$pF.2160@fed1read04...
>
> Well, okay, Steve. When I flew that equipment we often did autolands in
> good weather as part of the continuing certification of the system for CAT
> III operations.
>

Fine, there's no problem with that.


>
> And, an air carrier flight could be going into a non-towered airport using
> the ILS when the weather is "iffy" VFR.
>

We're not talking about "iffy" VFR, we're talking about good weather.


>
> The "need" to use couplers and perhaps autoland systems is determined by
> the carrier and it POI.
>

Well, their "need" to use couplers and perhaps autoland systems in good
weather does not give them priority over other users.

"Newps" > wrote in message
. ..
>
> The airlines will always fly the ILS if there is one up and running. They
> are required to.
>

Do you suppose you could cite that requirement? I've known many an airline
flight to do a visual approach when there was a perfectly good ILS approach
available.

Newps > wrote:

> The airlines will always fly the ILS if there is one up and running.
> They are required to.

Is this a FAR requirement or airline's operational procedural requirement?

--
Peter

"Peter R." > wrote in message
...
>
> Is this a FAR requirement or airline's operational procedural requirement?
>

Neither.

Peter R. wrote:

> Newps > wrote:
>
>
>>The airlines will always fly the ILS if there is one up and running.
>>They are required to.
>
>
> Is this a FAR requirement or airline's operational procedural requirement?

Both. The FAA makes sure the airline puts it into their ops specs. If
there is an operating ILS to the runway that they are landing on they
have to use it. If a controller clears pretty much any jet with no
restrictions on the size of the pattern almost without fail they will
turn final at the outer marker.

"Newps" > wrote in message
...
>
> Both. The FAA makes sure the airline puts it into their ops specs. If
> there is an operating ILS to the runway that they are landing on they have
> to use it. If a controller clears pretty much any jet with no
> restrictions on the size of the pattern almost without fail they will turn
> final at the outer marker.
>

Please cite the applicable FAR.

On Sun, 20 Nov 2005 18:04:57 -0800, wrote:

>Steven P. McNicoll wrote:
>
>> "Bob Gardner" > wrote in message
>> ...
>
>>
>> How many fields are there where this is a concern? I would expect most
>> fields with the congestion to require marked ILS critical areas to have
>> full-time towers.
>>
>>
>I can't provide a cite, but I was told recently that there are ILS
>critical areas at part-time towered airports.

Portland, ME. http://avn.faa.gov/d-tpp/0511/00329AD.PDF has one for
runway 29.

On Mon, 21 Nov 2005 09:48:30 -0600, "Jim Macklin"
> wrote:

>Limitations on the approach chart probably do not allow the
>ILS when the tower is closed or more than one hour after the
>last weather observation.
>

RW 29 at PWM has an ILS hold charted on the airport diagram, but I
don't see anything preventing it's use when the tower is closed on the
approach chart:
http://204.108.4.16/d-tpp/0511/00329IL29.PDF

Steven P. McNicoll wrote:

>

>
> Well, their "need" to use couplers and perhaps autoland systems in good
> weather does not give them priority over other users.
>
>
Did someone in this thread suggest there was any kind of priority issue
in the use of approach couplers or autoland systems?

Steven P. McNicoll wrote:

> "Peter R." > wrote in message
> ...
>
>>Is this a FAR requirement or airline's operational procedural requirement?
>>
>
>
> Neither.
>
>
91.129 requires that the ILS be followed at a Class D airport. It does
not require that the full procedure be flown. If cleared for a visual
to an ILS runway, for example, the 121 crew must have the ILS tuned and
identified and use it once lined up with the runway.

Further, this 91.129 requirement is included in every carrier's flight
operations policy manual (a POI-approved document) to be applied for any
runway end with an operating ILS, Class D or not.

>>wrong. There might be "need" to do autolanding for 3 month (?)
>>currency.
> It's not a problem because the pilots can see. The need for currency
> doesn't alter the weather.

correct but there is a need to do an autoland. It is not
*required* since the weather is good enough but the
need is still there.

>>I hear this often at night for jets going into SFO.
> SFO has a full-time tower.

correct but I was referring to jets asking to do a
CAT III approach for currency even though it is VFR.

Gerald

KP wrote:

> Man, I hate to side with McNicholl but...
>
> > wrote in message news:cjlgf.4216$pF.687@fed1read04...
>
>>Steven P. McNicoll wrote:
>>
> wrote in message news:CX9gf.1261$pF.1153@fed1read04...
>>>
>>>
>>>>It's a problem during a coupled approach especially if the pilot is
>>>>planning to do an autoland.
>>>>
>>>
>>>
>>>It's not a problem if the weather is good.
>>>
>>>
>>
>>Not so, Steve. It can cause control problems and certainly adversely
>>affect an autoland. That is why your handbook contains a caveat about
>>such approaches.
>>
>>Approach couplers and autoland systems are weather independent.~
>
>
> The only "caveat" in the .65 regarding coupled or autoland ILS approaches is
> in 3-7-5b. This simply requires an advisory to aircraft of "ILS/MLS
> CRITICAL AREA NOT PROTECTED" when the weather is at or above 800-2.
>
> So, if the weather is good (or good enough) all the pilot executing a
> coupled or autoland gets is a warning (ie, a reminder not to trust the
> electrons too much). For all practical purposes the ILS critical areas are
> not in play. Nobody gets held at the instrument hold lines. In other
> words, it's not a problem if the weather is good.

You're a bit out of context. Here is the context:

b. Air carriers commonly conduct "coupled" or "autoland" operations to
satisfy maintenance, training, or reliability program requirements.
Promptly issue an advisory if the critical area will not be protected
when an arriving aircraft advises that a "coupled," "CATIII,"
"autoland," or similar type approach will be conducted and the weather
is reported ceiling of 800 feet or more, and the visibility is 2 miles
or more.

When the weather is good, the crew is required to advise the tower when
they intend to do an autoland or even a non-autoland coupled approach.
If the advisory you mentioned is NOT issued then the crew is trained to
expect that the tower is protecting the critical areas.

The language used to be stronger, in that ATC was required to protect
the critical areas when the crew made such an announcement in good
weather. Apparently, that was too burdensome.

Nonetheless, most of the time when the crew announces its intent to do
an autoland/coupled approach in good weather, the tower does not issue
that alert, thus the crew can expect the ILS to perform without
interference.

De-creeping the thread a bit: the thread is about an airport without a
tower or a closed tower. A savvy air carrier crew would give serious
pause to considering a good-weather autoland at such an airport.

Steven P. McNicoll wrote:
> > wrote in message news:cjlgf.4216$pF.687@fed1read04...
>
>>Not so, Steve. It can cause control problems and certainly adversely
>>affect an autoland. That is why your handbook contains a caveat about
>>such approaches.
>>
>>Approach couplers and autoland systems are weather independent.~
>>
>
>
> You're mistaken. There's no need for approach couplers and autoland systems
> when the weather is good. It's not a problem because the pilots can see.
>
>
FAA 7110.65
3-7-5. PRECISION APPROACH CRITICAL AREA

b. Air carriers commonly conduct "coupled" or "autoland" operations to
satisfy maintenance, training, or reliability program requirements.
Promptly issue an advisory if the critical area will not be protected
when an arriving aircraft advises that a "coupled," "CATIII,"
"autoland," or similar type approach will be conducted and the weather
is reported ceiling of 800 feet or more, and the visibility is 2 miles
or more.

JPH

> wrote in message news:l6wgf.4657$pF.1345@fed1read04...
>
> Did someone in this thread suggest there was any kind of priority issue in
> the use of approach couplers or autoland systems?
>

Yes.

"Gerald Sylvester" > wrote in message
. net...
>
> correct but there is a need to do an autoland. It is not
> *required* since the weather is good enough but the
> need is still there.
>

Don't be silly. There's clearly no need to do an autoland in good weather.


>
> correct but I was referring to jets asking to do a
> CAT III approach for currency even though it is VFR.
>

We're talking about ILS critical areas when the tower is closed.

> wrote in message news:Sjwgf.4659$pF.917@fed1read04...
>
> You're a bit out of context. Here is the context:
>
> b. Air carriers commonly conduct "coupled" or "autoland" operations to
> satisfy maintenance, training, or reliability program requirements.
> Promptly issue an advisory if the critical area will not be protected when
> an arriving aircraft advises that a "coupled," "CATIII," "autoland," or
> similar type approach will be conducted and the weather is reported
> ceiling of 800 feet or more, and the visibility is 2 miles or more.
>
> When the weather is good, the crew is required to advise the tower when
> they intend to do an autoland or even a non-autoland coupled approach. If
> the advisory you mentioned is NOT issued then the crew is trained to
> expect that the tower is protecting the critical areas.
>

You're more than a bit out of context. There is no tower to advise as we're
talking about ILS critical areas when the tower is closed.

"JPH" > wrote in message
news:V8xgf.38889$4n5.27102@dukeread01...
>
> FAA 7110.65
> 3-7-5. PRECISION APPROACH CRITICAL AREA
>
> b. Air carriers commonly conduct "coupled" or "autoland" operations to
> satisfy maintenance, training, or reliability program requirements.
> Promptly issue an advisory if the critical area will not be protected when
> an arriving aircraft advises that a "coupled," "CATIII," "autoland," or
> similar type approach will be conducted and the weather is reported
> ceiling of 800 feet or more, and the visibility is 2 miles or more.
>

That can only be done when the tower is open, we're talking about ILS
critical areas when the tower is closed.

> wrote in message news:rbwgf.4658$pF.1342@fed1read04...
>
> 91.129 requires that the ILS be followed at a Class D airport. It does
> not require that the full procedure be flown. If cleared for a visual to
> an ILS runway, for example, the 121 crew must have the ILS tuned and
> identified and use it once lined up with the runway.
>

The requirement in FAR 91.129 is that a large or turbine-powered airplane
approaching to land on a runway served by an ILS must fly at an altitude at
or above the glide slope. The claim by Newps was; "The airlines will always
fly the ILS if there is one up and running. They are required to."

Steven P. McNicoll wrote:

> > wrote in message news:rbwgf.4658$pF.1342@fed1read04...
>
>>91.129 requires that the ILS be followed at a Class D airport. It does
>>not require that the full procedure be flown. If cleared for a visual to
>>an ILS runway, for example, the 121 crew must have the ILS tuned and
>>identified and use it once lined up with the runway.
>>
>
>
> The requirement in FAR 91.129 is that a large or turbine-powered airplane
> approaching to land on a runway served by an ILS must fly at an altitude at
> or above the glide slope. The claim by Newps was; "The airlines will always
> fly the ILS if there is one up and running. They are required to."
>
>
I didn't infer that he meant the full procedure. But, perhaps he did.
Newps?

Steven P. McNicoll wrote:

> > wrote in message news:l6wgf.4657$pF.1345@fed1read04...
>
>>Did someone in this thread suggest there was any kind of priority issue in
>>the use of approach couplers or autoland systems?
>>
>
>
> Yes.
>
>
Help me with a reference if you can.

Steven P. McNicoll wrote:

> > wrote in message news:Sjwgf.4659$pF.917@fed1read04...
>
>>You're a bit out of context. Here is the context:
>>
>>b. Air carriers commonly conduct "coupled" or "autoland" operations to
>>satisfy maintenance, training, or reliability program requirements.
>>Promptly issue an advisory if the critical area will not be protected when
>>an arriving aircraft advises that a "coupled," "CATIII," "autoland," or
>>similar type approach will be conducted and the weather is reported
>>ceiling of 800 feet or more, and the visibility is 2 miles or more.
>>
>>When the weather is good, the crew is required to advise the tower when
>>they intend to do an autoland or even a non-autoland coupled approach. If
>>the advisory you mentioned is NOT issued then the crew is trained to
>>expect that the tower is protecting the critical areas.
>>
>
>
> You're more than a bit out of context. There is no tower to advise as we're
> talking about ILS critical areas when the tower is closed.
>
>
And, the context of ILS critical areas when a tower is closed would
logically include a discussion of the similarities to an airport that
has an ILS but no control tower.

Steven P. McNicoll wrote:

> "Jose" > wrote in message
> . ..
>
>>Sure it is. The fuel vendor is a machine. It doesn't sleep, and never
>>leaves the airport.
>>
>
>
> The fuel vendor is typically a person.
>
>
You have to get out more, Steve.

> wrote in message news:Sjwgf.4659$pF.917@fed1read04...
> KP wrote:
>
>> Man, I hate to side with McNicholl but...
>>
>> > wrote in message news:cjlgf.4216$pF.687@fed1read04...
>>
>>>Steven P. McNicoll wrote:
>>>
> wrote in message
>>>>news:CX9gf.1261$pF.1153@fed1read04...
>>>>
>>>>
>>>>>It's a problem during a coupled approach especially if the pilot is
>>>>>planning to do an autoland.
>>>>>
>>>>
>>>>
>>>>It's not a problem if the weather is good.
>>>>
>>>>
>>>
>>>Not so, Steve. It can cause control problems and certainly adversely
>>>affect an autoland. That is why your handbook contains a caveat about
>>>such approaches.
>>>
>>>Approach couplers and autoland systems are weather independent.~
>>
>>
>> The only "caveat" in the .65 regarding coupled or autoland ILS approaches
>> is in 3-7-5b. This simply requires an advisory to aircraft of "ILS/MLS
>> CRITICAL AREA NOT PROTECTED" when the weather is at or above 800-2.
>>
>> So, if the weather is good (or good enough) all the pilot executing a
>> coupled or autoland gets is a warning (ie, a reminder not to trust the
>> electrons too much). For all practical purposes the ILS critical areas
>> are not in play. Nobody gets held at the instrument hold lines. In
>> other words, it's not a problem if the weather is good.
>
> You're a bit out of context.

I don't think I am.

>Here is the context:
> b. Air carriers commonly conduct "coupled" or "autoland" operations to
> satisfy maintenance, training, or reliability program requirements.
> Promptly issue an advisory if the critical area will not be protected when
> an arriving aircraft advises that a "coupled," "CATIII," "autoland," or
> similar type approach will be conducted and the weather is reported
> ceiling of 800 feet or more, and the visibility is 2 miles or more.

If you're reading that to mean that unless the advisory is issued the
critical areas are protected you're not only out of context you don't know
controllers or how the ATC system works.

> When the weather is good, the crew is required to advise the tower when
> they intend to do an autoland or even a non-autoland coupled approach. If
> the advisory you mentioned is NOT issued then the crew is trained to
> expect that the tower is protecting the critical areas.

Controllers are not going to protect the critical areas (ie, tie up useable
taxiway space and slow down traffic) unless they have a specific foreseeable
requirement to do so (ie, weather below 800-2). They certainly aren't going
to do it on the off-chance some air carrier *might* advise it is doing a
coupled or autoland approach.

If the weather is above 800-2 (ie, good) and ATC is not protecting the
critical areas (which they will not be), then they are required to issue the
advisory when the aircraft tells them it will be making a "coupled" or
"autoland" approach. If they're not issuing the advisory under those
conditions it's because they forgot.

I can't help what crews may or may not be trained to do or expect. If
they're taught to assume that absent an advisory the ILS critical areas are
protected when the weather is above 800-2 they're being taught to make an
unrealistic and potentially dangerous assumption.

> The language used to be stronger, in that ATC was required to protect the
> critical areas when the crew made such an announcement in good weather.
> Apparently, that was too burdensome.

There hasn't been any requirement to protect the critical areas for coupled
or autoland approaches or any other reason when the weather was above 800-2
for the last 27 years or more.

If there ever was (which I doubt) it was very short-lived. Apart from the
sheer physical impracticality of such a requirement, I seriously doubt even
the FAA would put in place a requirement that would delay or otherwise screw
other users of the system in order for some air carrier to fill one of their
internal proficiency/equipment check squares.

> Nonetheless, most of the time when the crew announces its intent to do an
> autoland/coupled approach in good weather, the tower does not issue that
> alert, thus the crew can expect the ILS to perform without interference.

Assuming the tower is protecting the ILS critical areas when the weather is
above 800-2 simply because no advisory is issued is an unrealistic and
potentially dangerous assumption on the part of the aircrew. The smarter,
safer, and more likely assumption would be the tower forgot to issue the
advisory.

> De-creeping the thread a bit: the thread is about an airport without a
> tower or a closed tower. A savvy air carrier crew would give serious
> pause to considering a good-weather autoland at such an airport.

As you're the one who brought the .65 (ie, controllers, their duty
requirements, and thus a situation where the tower is open) into the thread
it's only fair you should be the one to de-creep it.

And when the tower *is* open that aircrew would be equally savvy not to
assume the critical areas are protected simply because ATC forgot to issue
an advisory.

wrote:

>>
> I didn't infer that he meant the full procedure. But, perhaps he did.
> Newps?

No of course not. Only an idiot would infer that. If there is an
operating ILS to the runway they are landing on they must use them for
that time they are on final. They can still turn final where ever they
want, although as I said before they will almost always turn at the
marker if you let them.

> wrote in message news:CYBgf.4677$pF.224@fed1read04...
> Steven P. McNicoll wrote:
>
>> > wrote in message news:Sjwgf.4659$pF.917@fed1read04...
>>
>>>You're a bit out of context. Here is the context:
>>>
>>>b. Air carriers commonly conduct "coupled" or "autoland" operations to
>>>satisfy maintenance, training, or reliability program requirements.
>>>Promptly issue an advisory if the critical area will not be protected
>>>when an arriving aircraft advises that a "coupled," "CATIII," "autoland,"
>>>or similar type approach will be conducted and the weather is reported
>>>ceiling of 800 feet or more, and the visibility is 2 miles or more.
>>>
>>>When the weather is good, the crew is required to advise the tower when
>>>they intend to do an autoland or even a non-autoland coupled approach. If
>>>the advisory you mentioned is NOT issued then the crew is trained to
>>>expect that the tower is protecting the critical areas.
>>>
>>
>> You're more than a bit out of context. There is no tower to advise as
>> we're talking about ILS critical areas when the tower is closed.
>
> And, the context of ILS critical areas when a tower is closed would
> logically include a discussion of the similarities to an airport that has
> an ILS but no control tower.
>

Okay. One of the similarities between airports that have an ILS but no
control tower and airports that have an ILS and a closed control tower is
that there is no tower to advise of an autoland or a non-autoland coupled
approach and no tower to protect the ILS critical area.

Steven P. McNicoll wrote:
> "Gerald Sylvester" > wrote in message
> . net...
>
>>correct but there is a need to do an autoland. It is not
>>*required* since the weather is good enough but the
>>need is still there.
> Don't be silly. There's clearly no need to do an autoland in good weather.

You see the reasons it is required to do
autolandings in good weather (not to land the plane but for currency)
and you still can't admit you are wrong. There is a need to do
autolandings but it isn't required to safely land the plane for
that particular approach. It is simply for currency and when
the need arrises.

I had you killfiled for a while and now I gotta admit you really
provide some good entertainment. So are you the debate club captain
in the high school you attend?

Gerald

"Gerald Sylvester" > wrote in message
. com...
>
> You see the reasons it is required to do
> autolandings in good weather (not to land the plane but for currency)
> and you still can't admit you are wrong.
>

I have no problem admitting when I'm wrong, but I certainly am not going to
say I'm wrong when I'm right.

KP wrote:

> As you're the one who brought the .65 (ie, controllers, their duty
> requirements, and thus a situation where the tower is open) into the thread
> it's only fair you should be the one to de-creep it.

No, I brought in the .65 language after someone else had quoted the
alert language contained in that order.
>
> And when the tower *is* open that aircrew would be equally savvy not to
> assume the critical areas are protected simply because ATC forgot to issue
> an advisory.
>
>
Here is what AIM 1-9-9 k says about it and has said pretty much the same
thing for a long time. Note the phrase "to ensure that the ILS critical
areas are protected..." (during weather better than 800-2):

(2) Glide Slope Critical Area. Vehicles and aircraft are not authorized
in the area when an arriving aircraft is between the ILS final approach
fix and the airport unless the aircraft has reported the airport in
sight and is circling or side stepping to land on a runway other than
the ILS runway.

(b) Weather Conditions. At or above ceiling 800 feet and/or visibility 2
miles.

(1) No critical area protective action is provided under these conditions.

(2) A flight crew, under these conditions, should advise the tower that
it will conduct an AUTOLAND or COUPLED approach to ensure that the ILS
critical areas are protected when the aircraft is inside the ILS MM.

I guess the AIM tells pilots one thing and controllers tell controllers
another thing. That has been going on for a lot longer than 27 years.

Steven P. McNicoll wrote:
> "Gerald Sylvester" > wrote in message
> . com...
>
>>You see the reasons it is required to do
>>autolandings in good weather (not to land the plane but for currency)
>>and you still can't admit you are wrong.
>>
>
>
> I have no problem admitting when I'm wrong, but I certainly am not going to
> say I'm wrong when I'm right.
>
>
Gerald apparently is new to your "unique" style.

I know I am going to regret this: your share your knowledge better than
you used to, you're often less obtuse than you used to be, and of course
you generally (but not always) know what you're talking about.

Newps wrote:

>
>
> wrote:
>
>>>
>> I didn't infer that he meant the full procedure. But, perhaps he did.
>> Newps?
>
>
> No of course not. Only an idiot would infer that. If there is an
> operating ILS to the runway they are landing on they must use them for
> that time they are on final. They can still turn final where ever they
> want, although as I said before they will almost always turn at the
> marker if you let them.

As always, you have the "fleck" without having to prove something.

"Steven P. McNicoll" > wrote in
k.net:


> Well, if it's only a problem when an aircraft is on the ILS and it's
> below 800/2, and given that ATC isn't going to release an IFR
> departure if an aircraft is on the ILS, then it doesn't appear to be a
> problem.
>

I am familiar with at least one airport that has a Runup area and Hold
Short line inside the ILS critical area. As such, it would seem that the
above statement is inaccurate, as a plane that has not been released could
mistakenly travel past the ILS hold line and create a disruption for an
landing plane.

"Steven P. McNicoll" > wrote in news:vpcgf.3552
:

>
> "Jose" > wrote in message
> . ..
>>
>> Sure it is. The fuel vendor is a machine. It doesn't sleep, and never
>> leaves the airport.
>>
>
> The fuel vendor is typically a person.

1) Self-Serve fuel. Many airports have it. They even take credit cards.

2) Many maintenance facilities open before towers, to prep planes before
they take off. At HPN, tower opens at 6am EST. However, every FBO on the
field with which I am familiar opens at 5amEST or earlier. Two of them even
offer 24 hour service.

"Judah" > wrote in message
. ..
>
> I am familiar with at least one airport that has a Runup area and Hold
> Short line inside the ILS critical area. As such, it would seem that the
> above statement is inaccurate, as a plane that has not been released could
> mistakenly travel past the ILS hold line and create a disruption for an
> landing plane.
>

Yes, it could. It could also mistakenly travel past the runway holding
position line and create an obstacle for a landing plane. But both of these
mistakes could happen at a field with an operating control tower, so they
seem to be a bit outside this discussion.

"Judah" > wrote in message
. ..
>
> 1) Self-Serve fuel. Many airports have it. They even take credit cards.
>

Yes, but most airports do not have self-serve fuel. At most airports with
fuel service the fuel vendor is a person.

> It could also mistakenly travel past the runway holding
> position line and create an obstacle for a landing plane. But both of these
> mistakes could happen at a field with an operating control tower, so they
> seem to be a bit outside this discussion.

Should those mistakes happen at an airport with an operating control
tower, the tower controller would catch the error and "nudge the
airplane back where it belongs". This cannot happen at an airport
without an operating control tower, making this right smack inside this
discussion.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

"Jose" > wrote in message
...
>
> Should those mistakes happen at an airport with an operating control
> tower, the tower controller would catch the error and "nudge the airplane
> back where it belongs".

Only if he can see the airplane. That's frequently not possible in reduced
visibility situations, such as those that would necessitate an ILS approach
in the first place.

> With weather below 800/2, the only people in the vicinity of the
> ILS critical area would be IFR departures, right?

I can fly all day in 800/2 in my Champ.
All I need is 1 sm and clear of clouds.
At 70 mph, it takes a while to get anywhere.

"john smith" > wrote in message
...
>
> I can fly all day in 800/2 in my Champ.
> All I need is 1 sm and clear of clouds.
> At 70 mph, it takes a while to get anywhere.
>

Perhaps all night, but probably not all day. The operating hours of
part-time towers tend to be the daytime hours, so the hours that you can fly
with only one mile visibility while remaining clear of clouds tend to be
just the nighttime hours. Your Champ' will be limited to operating in an
airport traffic pattern within 1/2 mile of the runway, assuming it has the
required lighting.

"Steven P. McNicoll" > wrote in
ink.net:

>
> "Jose" > wrote in message
> ...
>>
>> Should those mistakes happen at an airport with an operating control
>> tower, the tower controller would catch the error and "nudge the
>> airplane back where it belongs".
>
> Only if he can see the airplane. That's frequently not possible in
> reduced visibility situations, such as those that would necessitate an
> ILS approach in the first place.

Is the control tower at your field 800'AGL?

"Steven P. McNicoll" > wrote in
ink.net:

>
> "Judah" > wrote in message
> . ..
>>
>> 1) Self-Serve fuel. Many airports have it. They even take credit
>> cards.
>>
>
> Yes, but most airports do not have self-serve fuel. At most airports
> with fuel service the fuel vendor is a person.

At most of these airports, the fuel vendor person arrives before the Tower
opens, specifically to service the planes that will be taking off first.
It's pretty much the sensible thing to do. If they show up at the same time
that the tower opens, they won't be able to get the planes ready until
later.

"Judah" > wrote in message
. ..
>
> Is the control tower at your field 800'AGL?
>

Nope.

"Judah" > wrote in message
.. .
>
> At most of these airports, the fuel vendor person arrives before the Tower
> opens, specifically to service the planes that will be taking off first.
> It's pretty much the sensible thing to do. If they show up at the same
> time
> that the tower opens, they won't be able to get the planes ready until
> later.
>

How many of those airports park the aircraft to be fueled within the ILS
critical areas?

In article t>,
"Steven P. McNicoll" > wrote:

> "john smith" > wrote in message
> ...
> >
> > I can fly all day in 800/2 in my Champ.
> > All I need is 1 sm and clear of clouds.
> > At 70 mph, it takes a while to get anywhere.
> >
>
> Perhaps all night, but probably not all day. The operating hours of
> part-time towers tend to be the daytime hours, so the hours that you can fly
> with only one mile visibility while remaining clear of clouds tend to be
> just the nighttime hours. Your Champ' will be limited to operating in an
> airport traffic pattern within 1/2 mile of the runway, assuming it has the
> required lighting.

For CB/CC/CDAS, yes.
Some CDAS will give you a Special if you ask for it.

"john smith" > wrote in message
...
>
> For CB/CC/CDAS, yes.
>

No, for Class G airspace.


>
> Some CDAS will give you a Special if you ask for it.
>

Class D airspace when the tower is closed? Special VFR is available only in
a surface area, but SVFR also requires separation from IFR aircraft.

"Steven P. McNicoll" > wrote in
ink.net:

>
> "Judah" > wrote in message
> .. .
>>
>> At most of these airports, the fuel vendor person arrives before the
>> Tower opens, specifically to service the planes that will be taking
>> off first. It's pretty much the sensible thing to do. If they show up
>> at the same time
>> that the tower opens, they won't be able to get the planes ready
>> until later.
>>
>
> How many of those airports park the aircraft to be fueled within the
> ILS critical areas?

The OP did not suggest that planes parked in the ILS Critical areas.

Here's the original quote:
> People may be taxiing around the airport with no intention of taking off,
> for example, to fuel up, to do maintanance, or to more the aircraft.

Come on now, Steven. Either I'm getting better at this, or you're pulling a
me.

"Jose" > wrote in message
. ..
> > the weather is below 800/2, in which case only IFR departures
> > will be of concern
>
> People may be taxiing around the airport with no intention of taking
> off, for example, to fuel up, to do maintanance, or to more the aircraft.
>
> I suppose such an aircraft could call departure first, to ensure that
> such operation will not interfere with anybody on approach.
>
> Jose

I still would like someone to explain how this does not reinforce the
original poster's question.. Suppose someone just needs to taxi around near
the approach end of the rwy. they can, yes? nobody to stop them?

--
Mike Teague - Vancouver WA, USA
-- Opie and Anthony - XM202 - O&A Party Rock!
-- Phil Hendrie = Radio Genius