ILS critical area

[saviboy]

has someone already been told to hold at the ILS critical area Hold short line.
If yes, what are the conditions required for ATC to ask you to hold?
I looked in the aim, and I didnt find anything on the reasons.

 

[bafanguy]

Don't have the FAA source document in front of me, but our Ops Specs ( which is driven by official FAA stuff ) says:


Weather less than 800 ft ceiling or visibility 2 miles or less, ILS critical areas are protected.


There's a bit more to it than that alone, but that's the trigger point. Maybe the Air Traffic Controller Handbook has more details since they're the ones who start the process.

 

[PIREP]

has someone already been told to hold at the ILS critical area Hold short line.
If yes, what are the conditions required for ATC to ask you to hold?
I looked in the aim, and I didnt find anything on the reasons.

Look in section 1-1-19 (Instrument Landing System) subsection k (ILS Course Distortion) of the AIM

 

[saviboy]

Thanks for the reply. and I found it under 1-1-9 subpart K

 

[dicksonk1821]

Also we pilots are to hold short of the ILS critical area if there is and aircrat between the outer marker and the runway (don't remember exactly what it says, but that is the gist of it). We are also responsible to remember to hold short the controller does not necessarily have to tell us even though they should.

 

[ILStoMinimums]

Can somebody post what the AIM says on the board please?

 

[dicksonk1821]

The best I can tell you is to go and get a copy of the FAR/AIM and read up on all of this. You can learn so much from reading this and rereading the material. It also helps to distinguish the grey areas of the book that we can not tell you in a short paragraph. Don't let us tell you the reg's you should read the material yourself and then come back with questions. After all, it is you responsibility to be up-to-date with all of this material. That is what I tell my students.

 

[CA1900]

Also we pilots are to hold short of the ILS critical area if there is and aircrat between the outer marker and the runway (don't remember exactly what it says, but that is the gist of it). We are also responsible to remember to hold short the controller does not necessarily have to tell us even though they should.

That's incorrect.

ATC is charged with protecting the ILS critical area, not the pilot. You won't find anything in the FARs about holding short when an airplane is inside the outer marker because you have no idea where the airplanes are on approach.

Here's the ATC directive:
http://www.faa.gov/ATpubs/ATC/Chp3/atc0307.html#3-7-5

 

[Dr Pokenhiemer]

Without looking at the AIM, basically the ILS Critical Area hold line is in effect when the weather is down to or close to minimums. ATC will advise when to hold short of that line. When ATC doesn't advise of the critical line, it is understood to hold at the runway hold short line.

 

[Flymach2]

Hi...

No offense, but if you're on the computer, this stuff is right at your fingertips.

From the AIM



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.


​

​

Regards

 

[FlyChicaga]

That makes it pretty clear. It's 800 and 2 and when inside the FAF. So this means ATC can clear an aircraft into position and hold if the aircraft on the ILS is outside the FAF. This does not mean when it is 1200 and 3 an aircraft cannot go past the ILS hold short line if a landing aircraft is within the FAF.

It's very simple: When it's 800 and 2 or below, then stop at the ILS hold short line. Then, move across it when ATC directs you to. You cannot determine where the aircraft is on the approach, so you must trust ATC.

 

[Rez O. Lewshun]

And what about autoflight. Many autopilots are usable to 80ft above TDZE. Cat II and III to the surface.

From the Feds;

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.
​

Here is the scenario: ATC issues visual approach clearance during VMC operations. Crew uses ILS to "backup" the visual approach and also chooses to use autoflight to 80ft. Heavy jet then blocks LOC/GS transmitter and needles go "wild" at 100ft......

Thoughts?

 

[fokkers&beer]

If ATC has'nt issued a hold short clearance you dont need to hold short of the critical line. In fact it could be disadvantageous to do so. An example would be if the critical line is a ways back from the runway, it could mean extra time to get in to position if they were expecting you to make a quick departure. It is ATC's responsibility to give you hold short of the critical area instructions. One can not just assume because it is less than 800 and 2 that you hold short. There may not even be anyone on the approach, you just don't know.

 

[TonyC]

That makes it pretty clear.

It's very simple:

And yet you seem to have missed the most important part:

2. ATC issues control instructions ...

Follow those instructions. Simple.


.

 

[vetteracer]

Quote

ATC is charged with protecting the ILS critical area, not the pilot. You won't find anything in the FARs about holding short when an airplane is inside the outer marker because you have no idea where the airplanes are on approach.


This may be true, but at an uncontrolled field, you are to announce final app fix inbound. Is this to warn aircraft on the ground??

If I am at an uncontrolled airport, and I am taxiing out, and I hear an aircraft announce "Final app fix Inbound", I hold short of the ILS CRIT area. Not sure if this has anything to do with non-radar comp-reporting points or not.

Not sure, just some food for thought.

 

[groundpointsix]

Quote

ATC is charged with protecting the ILS critical area, not the pilot. You won't find anything in the FARs about holding short when an airplane is inside the outer marker because you have no idea where the airplanes are on approach.


This may be true, but at an uncontrolled field, you are to announce final app fix inbound. Is this to warn aircraft on the ground??

If I am at an uncontrolled airport, and I am taxiing out, and I hear an aircraft announce "Final app fix Inbound", I hold short of the ILS CRIT area. Not sure if this has anything to do with non-radar comp-reporting points or not.

Not sure, just some food for thought.

Technically you are only required to inform ATC of final approach fix inbound. An uncontrolled field is just that-- uncontrolled. You can call FAF inbound, but you have no guaruntee that Joe Dumbass isn't going to taxi out and take-off scud running. I agree that it's a good idea to hold at the ILS Hold Bars, but I wouldn't be expecting anyone else to while I'm flying the approach.