LOC only approaches

Pietrantonio

Pietrantonio

Well-Known Member
Just curious how this works. Suppose the aircraft has a VOR with no glideslope capability. The glideslope doesn't fail in-flight. It just doesn't have one at all. Now, ATC clears you for the ILS XYZ approach (The approach is ILS or LOC/DME XY). Do we, as pilots, ask ATC for a LOC clearance instead, or just fly the LOC approach as published without asking ATC.

Would it be advised to include "no glidescope" in the remarks section of the flight plan?
 
Realistically I would just fly the approach as long as it states OR LOC XX, so you know you're legal. Now days we all basically assume everyone is /G but it doesn't hurt to verify with the controller. Most I work with would have no idea that there is such a thing as a plane that can't fly an ILS... might be good learning for them haha. Now if the GS is out on the ILS we do have to legally tell you that or clear you for the LOC only.
 
Technically speaking you'd want to seek clearance for the named procedure your can fly. I have plenty of pilots ask for clarification and clearance for the "Localizer" approach specifically when the procedure states "ILS or LOC."

The type of approach, in the radar environment, can help us determine when you're at an unsafe altitude on the descent. Pilots who "dive and drive" often set off our automated altitude alarm (MSAW - Minimum Safe Altitude Warning) on non precision approaches. It's nice to be able to know "oh, they're on the LOC approach and still above the step down fix / MDA, they're good" instead of "huh, they're below the glideslope, I should issue an alert and freak them out."
 
FM_Weasel said:
Technically speaking you'd want to seek clearance for the named procedure your can fly. I have plenty of pilots ask for clarification and clearance for the "Localizer" approach specifically when the procedure states "ILS or LOC."

The type of approach, in the radar environment, can help us determine when you're at an unsafe altitude on the descent. Pilots who "dive and drive" often set off our automated altitude alarm (MSAW - Minimum Safe Altitude Warning) on non precision approaches. It's nice to be able to know "oh, they're on the LOC approach and still above the step down fix / MDA, they're good" instead of "huh, they're below the glideslope, I should issue an alert and freak them out."
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Not to mention if the weather is down bear LOC mins but plenty good for an GS approach, the controller may be kind of surprised when you go around due to not finding the runway.
 
FM_Weasel said:
Technically speaking you'd want to seek clearance for the named procedure your can fly. I have plenty of pilots ask for clarification and clearance for the "Localizer" approach specifically when the procedure states "ILS or LOC."

The type of approach, in the radar environment, can help us determine when you're at an unsafe altitude on the descent. Pilots who "dive and drive" often set off our automated altitude alarm (MSAW - Minimum Safe Altitude Warning) on non precision approaches. It's nice to be able to know "oh, they're on the LOC approach and still above the step down fix / MDA, they're good" instead of "huh, they're below the glideslope, I should issue an alert and freak them out."
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Are you not REQUIRED to issue a Low Alt alert if you get a MSAW regardless of the type of approach and even if the aircraft is above the MDA, DA ,DH? I belive you do !
 
queeno said:
Are you not REQUIRED to issue a Low Alt alert if you get a MSAW regardless of the type of approach and even if the aircraft is above the MDA, DA ,DH? I belive you do !
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I do not believe you do.

2−1−6. SAFETY ALERT
Issue a safety alert to an aircraft if you are aware the
aircraft is in a position/altitude that, in your judgment,
places it in unsafe proximity to terrain, obstructions,
or other aircraft. Once the pilot informs you action is
being taken to resolve the situation, you may
discontinue the issuance of further alerts. Do not
assume that because someone else has responsibility
for the aircraft that the unsafe situation has been
observed and the safety alert issued; inform the
appropriate controller.

NOTE-
2. Recognition of situations of unsafe proximity may result
from MSAW/E−MSAW/LAAS, automatic altitude readouts,
Conflict/Mode C Intruder Alert, observations on a PAR
scope, or pilot reports.
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a. Terrain/Obstruction Alert. Immediately issue/
initiate an alert to an aircraft if you are aware the
aircraft is at an altitude that, in your judgment, places
it in unsafe proximity to terrain and/or obstructions.
Issue the alert as follows:
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The operative condition here is that, in your judgment, the aircraft appears to be at an unsafe altitude. I do not consider aircraft that are at or above minimum altitudes to be in an unsafe situation requiring a safety alert.

The alerts are, of course, predictive in nature. The automated system does not understand that a pilot intends to level off shortly. All it sees is a descent rate consistent with transgressing the minimum altitude threshold for that area. I also don't give traffic alerts when a Conflict Alert(CA) is triggered AFTER the aircraft have already passed each other (this happens). Nor, to aircraft in the pattern that occasionally trigger alarms due to their close proximity to the aircraft they're already following.
 
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It's never an issue for me; as ATC has always issued the clearance for the approach I have requested.
 
Well it may have been local, i was at a team breifing at C90 and we were told to issue low alt warning to any aircraft inside the FAF on any approach including VA if there was an MSAW. or at least advise the tower about it. there may have been a GENOT on it at one time.
 
Our SOP requires notifying the tower or other responsible controller. Interestingly, it does not require that second controller to actually issue the alert to the aircraft. That's where the ATC manual comes in with "judgment."

So we make a lot of nuisance land line calls.
 
queeno said:
Well it may have been local, i was at a team breifing at C90 and we were told to issue low alt warning to any aircraft inside the FAF on any approach including VA if there was an MSAW. or at least advise the tower about it. there may have been a GENOT on it at one time.
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I've never heard of issuing a low altitude alert just because of the alarm to an aircraft doing a visual approach.
Even when I tell aircraft to descend and maintain an altitude (usually the MVA,) I'll get an msaw alert on occasion just based on their descent rate and what the system predicts the aircraft to be at in one minute and also in thirty seconds. If I think the aircraft is still at a good altitude I don't issue an alert.
 
Best i can remember there was an CFIT accident maybe early 2000s , tracon cleared AC for an approach (dont remember if it was an IFR or VA)to a SAT airport and switched the AC 9 to 10 miles out to tower. When the AC was 7 miles out there was an MSAW on this AC. tracon ASSUMED tower (it had a DBRITE) would give the alert but what no one knew was that the MSAW for the tower Dbrite was programed to give a MSAW only when the AC was in the Class D airspace. tower was busy and didnt notice the AC decend early. This is the reason we at C90 were given this direction. this was many years ago so memory aint the best anymore.
 
I don't know if there is a rule about this. I tend to doubt it since the plate is the same in the important respects of course and missed. But I would advise ATC I was flying it LOC-only because my descent profile will be different and may,depending on the approach, bring me well below glideslope at points. My theory is that it's always better for us if we and ATC are on the same page.
 
It's always good to learn from the ATC perspective. Thanks for the comments. I agree with MidlifeFlyer. I would feel better having said something so that we're all on the same page, rather than settings off alarms because I failed to request the LOC approach.
 
While I was flight instructing on the east coast back in 2008-2010 we would always get them from the tower on non-precision approaches. Maybe it was required back then, or maybe just another local procedure.
 
Where I work it's a misconception of what our manual says. I suppose it doesn't harm anything as long as the distraction isn't too great. Personally, it just seems like a really elevated response to a normal situation. Especially since the word "immediately" is used. In a perfect world, the software wouldn't generate alerts for aircraft complying with the approach profile. Unfortunately, it's just not that intelligent, and further filtering of the trigger might prevent alerts in genuine situations. That's why the human judgment factor is important.
 
Make sure you get cleared for the approach you're flying so ATC and you are on the same page so the proper procedures and level of safety is in place. The GS was out of service at my local airport for a few months, so I got really used to saying "Cleared for the Localizer 13 approach." I went to another airport with the ILS, and said "Cleared for the localizer 04 approach," and center snapped back saying "you were cleared for the ILS not the LOC approach, ask if you want the LOC approach instead." I quickly corrected my statement.
 
JustinS said:
Make sure you get cleared for the approach you're flying so ATC and you are on the same page so the proper procedures and level of safety is in place. The GS was out of service at my local airport for a few months, so I got really used to saying "Cleared for the Localizer 13 approach." I went to another airport with the ILS, and said "Cleared for the localizer 04 approach," and center snapped back saying "you were cleared for the ILS not the LOC approach, ask if you want the LOC approach instead." I quickly corrected my statement.
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I want to say I'm surprised that a controller would get snappy at something that small....but I'm not at all.
If I clear you for the ILS and you want to fly the LOC approach, have at it. But if I clear you for the LOC approach and you read back the ILS, I'll probably reiterate that it's a localizer only and the glideslope is out.
 
Stinger said:
I want to say I'm surprised that a controller would get snappy at something that small....but I'm not at all.
If I clear you for the ILS and you want to fly the LOC approach, have at it. But if I clear you for the LOC approach and you read back the ILS, I'll probably reiterate that it's a localizer only and the glideslope is out.
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Yes! Logic prevails somewhere! :)
 
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