ILS critical area when the tower is closed?

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
news

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.