ILS Critical Area Hold Line

[flyboyike]

I was recently asked if there were any weather parameters associated with an ILS Critical Area hold line going into effect. IOW, the person implied that the hold line went into effect when the weather went below certain minimums. The person never told me what those minimums are and I was under the impression that it went into effect when ATC said it was in effect. I couldn't find anything different either in FARs or AIM. Anyone know what these minimums are (if they exist)?

 

[Mongolikecandy]

Someone will correct me really soon but I think it goes into effect when weather is below 800 & 2.

*Disclaimer.... I am on furlough and have forgotten almost everything I have learned about flying.

 

[jegermeister]

800 and 2, when in doubt ask

 

[flyboyike]

800 and 2, when in doubt ask

Absolutely I agree about asking. Can you point me to where the 800 and 2 is in the regs? I'm not doubting you, I just want to know in case I have to point someone else to the reg in question.

 

[Andy Neill]

Here is an FAA Powerpoint presentation that has definitive answers:
http://www.faa.gov/runwaysafety/ace/presentations/6.ppt

 

[asayankee]

I was always under the impression that it was an ATC function....

 

[flyboyike]

Here is an FAA Powerpoint presentation that has definitive answers:
http://www.faa.gov/runwaysafety/ace/presentations/6.ppt

Thank you, Andy, but I'm afraid that presentation doesn't have a definitive answer to my question. It doesn't even mention weather minimums for the hold line.

 

[flyboyike]

I was always under the impression that it was an ATC function....

As was I. Operationally, I don't see why I should care what the minimums are, if they tell me to hold short of the ILS hold line, I'll do it, even if it's clear and a million.

 

[veneratio]

AIM 1-1-9

http://www.faa.gov/airports_airtraffic/air_traffic/publications/ATpubs/AIM/Chap1/aim0101.html#1-1-22

k. ILS Course Distortion
1. All pilots should be aware that disturbances to ILS localizer and glide slope courses may occur when surface vehicles or aircraft are operated near the localizer or glide slope antennas. Most ILS installations are subject to signal interference by either surface vehicles, aircraft or both. ILS CRITICAL AREAS are established near each localizer and glide slope antenna.
2. ATC issues control instructions to avoid interfering operations within ILS critical areas at controlled airports during the hours the Airport Traffic Control Tower (ATCT) is in operation as follows:
(a) Weather Conditions. Less than ceiling 800 feet and/or visibility 2 miles.
(1) Localizer Critical Area. Except for aircraft that land, exit a runway, depart or miss approach, vehicles and aircraft are not authorized in or over the critical area when an arriving aircraft is between the ILS final approach fix and the airport. Additionally, when the ceiling is less than 200 feet and/or the visibility is RVR 2,000 or less, vehicle and aircraft operations in or over the area are not authorized when an arriving aircraft is inside the ILS MM.
(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.

So ATC will tell you if they need you to hold short if the tower is open...

 

[Stifler's Mom]

Whoa Whoa Whoa.....what is this sharing of useful information on Flightinfo all about????

Moderators, delete this thread immediately!!!!!!!

 

[Stifler's Mom]

Andy and Veneratio,

Good stuff, thanks for the info.

Take a look at ATL's diagram.

http://upload.wikimedia.org/wikipedia/commons/d/dc/ATL_-_FAA_airport_diagram.png

You land on 8L like we were today doing CAT 2 approaches. you are told to join Bravo westbound to Victor. Along the way there is an ILS Hold Short sign. Do you keep going???? There's one at B1 and one at B2.

According to Veneratio's article, it looks like as a landing aircraft, you are not required to hold???

 

[flyboyike]

AIM 1-1-9

http://www.faa.gov/airports_airtraffic/air_traffic/publications/ATpubs/AIM/Chap1/aim0101.html#1-1-22

k. ILS Course Distortion
1. All pilots should be aware that disturbances to ILS localizer and glide slope courses may occur when surface vehicles or aircraft are operated near the localizer or glide slope antennas. Most ILS installations are subject to signal interference by either surface vehicles, aircraft or both. ILS CRITICAL AREAS are established near each localizer and glide slope antenna.
2. ATC issues control instructions to avoid interfering operations within ILS critical areas at controlled airports during the hours the Airport Traffic Control Tower (ATCT) is in operation as follows:
(a) Weather Conditions. Less than ceiling 800 feet and/or visibility 2 miles.
(1) Localizer Critical Area. Except for aircraft that land, exit a runway, depart or miss approach, vehicles and aircraft are not authorized in or over the critical area when an arriving aircraft is between the ILS final approach fix and the airport. Additionally, when the ceiling is less than 200 feet and/or the visibility is RVR 2,000 or less, vehicle and aircraft operations in or over the area are not authorized when an arriving aircraft is inside the ILS MM.
(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.

So ATC will tell you if they need you to hold short if the tower is open...

Thank you muchly for that. So, it sounds to me as though it's still up to ATC to tell you to hold short of that dang line, thus it's an ATC function either way, since there is no regulatory requirement to hold short thereof, unless told by ATC. Phew.

 

[veneratio]

Andy and Veneratio,

Good stuff, thanks for the info.

Take a look at ATL's diagram.

http://upload.wikimedia.org/wikipedia/commons/d/dc/ATL_-_FAA_airport_diagram.png

You land on 8L like we were today doing CAT 2 approaches. you are told to join Bravo westbound to Victor. Along the way there is an ILS Hold Short sign. Do you keep going???? There's one at B1 and one at B2.

According to Veneratio's article, it looks like as a landing aircraft, you are not required to hold???

I think that if they need you to hold than they will tell you.

 

[CRJFlyer]

Hold short when TOLD to hold short by ATC..Or as usually the case in LGA, the ATIS may broadcast to hold short... (but it's been awhile since I've been to LGA)

I've always been frustrated when a Captain holds short when nothing was said from ATC..Especially on a clear day.... Then again, it is just safer to hold short and ask questions later..So no harm no foul..

 

[Axel]

Regardless of the weather, if ATC says "hold short," then by golly I reckon you hold short. Thus speaketh Captain Obvious.

< 800 or 2, and not told to "hold short," hold short anyway. ATC will tell you to cross it. If ATC and/or another pilot and/or the right seat captain FO gets pissy about that, shrug and smile.