Circling straight-in?

[Typhoon1244]

A friend of mine came up with an interesting question:

Suppose you're going somewhere with a single runway...let's say it's 18-36. It's overcast, and you'll need an approach to get through the clouds. The only approach to the airport is an ILS to 18, but for some reason the straight-in minimums are NOTAMed as "not authorized."

Can you use the circling minimums and shoot a localizer 18 approach and circle-to-land 18? (I gotta admit, the thought never occured to me...)

 

[Super 80]

Wouldn't that be called a localizer approach?

I think the minimums would be lower too.

 

[EagleRJ]

Let's say the straight-in minimums are NOTAMed NA due to a crane on the final approach course.
As long as you see the runway using the circling minimums and can decend to the runway using normal maneouvers, nothing prevents you from landing straight in.
It's the same for some VOR-A and LOC-A approaches where the final approach course is within 30 degrees of the runway, but the approach leaves you with too much altitude to lose at the MAP. Nothing says you are required to land on another runway, or make a decending 360 to land. If you see the runway environment early enough, and you're in a plane that can make the descent safely, you can do it.

 

[avbug]

Correct. Circling minimums don't imply that one must circle, but only that obstacle clearance protection is gauranteed within the appropriate radial distance for your approach category.

Nothing implies that you cannot fly the approach as an ILS, even though you are restricted to circling minima only. Unless the glide slope is notam'd inop or unuseable, you can fly the ILS to circling minimums.

 

[labbats]

If something was posted as circle to land only, I don't think I'd shoot an ILS down below those minimums. Like someone said above, I don't see anything wrong with transitioning those criteria into a straight in LOC approach though. But let me say that I'd advise tower obviously, and barring any laughing/screaming from them, head on in on the LOC.

 

[Rick1128]

There are several approaches around the country like that. All that I have seen have been non-presision approaches with no LOC approaches. Like avbug said you can land straight in. The main one that comes to mind is Aspen (ASE).

 

[Typhoon1244]

But let me say that I'd advise tower obviously, and barring any laughing/screaming from them, head on in on the LOC.

This happened in South Bend. Our her requested the localizer 27 circle to land 27. The guy in approach control snickered, then cleared them as requested. Apparently the idea of a "circling/straight-in" had never occurred to him, either.

 

[nosehair]

The word "localizer" seems to have infested this thread. It does not matter whether you are using the LOC only or the full ILS with Glide Slope, you are restricted to "circling minimums". If you look at the approach plates, you will see "S-ILS", "S-LOC", each with their own straight-in minimums. On either approach, if you are going to leave the final approach path and circle to another runway, you must stay at circling mins untill in a position to start final descent for landing. A NOTAM that restricts you to circ-mins only must mean their is a temporary obstacle in the final approach path. Of course, we're talking being in IMC. Once you have visual with the runway, you can descend at you own discretion.

 

[avbug]

Correct, and as I stated before, if it's an ILS approach, you may fly the ILS. You are merely restricted to the higher circling minimums. There is no need to request circling to the runway when it's straight in (eg, circling to runway 27 while flying the ILS to runway 27). One isn't covering one's self legally, as it serves no purpose. Sort of reminds me of Austin Powers statement, "Please allow myself to introduce...myself."

Asking to circle to the runway when on a straight in approach served by the ILS is redundant. You may fly the ILS. You may only descend on the ILS to circling minimums, but this doesn't change anything; it's still an ILS approach. There is no need to revert to localizer-anything, unless the glideslope has been notam'd so. (By name, it still remains an ILS, weather the glideslope is inoperative, too).

The only issue with respect to the use of circling minimums is that the ILS minimums have been raised, and one cannot continue below that point without the requisite visual references in sight.

 

[mar]

One more base to cover?

Of course, no matter what, under 121 at least, you'll need to comply with all stabilized approach criteria but that sort of goes without saying so I'll just be quiet now.

Thanks for listening.

 

[profile]

If only the circling minimums are available, it indicates that the obstacle clearance or alignment criteria don't meet TERPs. If it's too steep of a gradient to allow for the straight in criteria, the only choice is to make it a circle. If a pilot can safely execute the straight in, that is ok, and light aircraft probably can do that without much problem. Larger jets likely would be unable to make it down in time. Also, all the obstacle clearance under the MDA is see and avoid, so it allows more flexibility for the procedure designers.

 

[Typhoon1244]

I just discussed this with my captain going into Madison, WI yesterday since the ILS 21 approach straight-in was NOTAMed out.

This captain wasn't tall and very thin with brown hair and glasses, by any chance?

 

[avbug]

You can do the ILS 21 approach, circle to 21.

Yes, but redundant. Once again, allow myself to introduce myself.

You can do the ILS 21 straight-in, using circling minimums as the minimum criteria. You simply can't descend below them until you have the required visual references. If the approach is a precision approach, by following the glideslope you are on a stabilized approach. If you don't see the runway at MDA on the glideslope, you can continue forward and plan to execute a circling approach if at some point the visual requirements are met, or simply continue to the MAP at MDA and go missed.

Personally, if wind favors Rwy 21 and I'm flying the ILS to 21, I'm not going to circle back around to land if I don't have the runway in sight at MDA on the glide slope. I'm going missed.

 

[Typhoon1244]

Personally, if wind favors Rwy 21 and I'm flying the ILS to 21, I'm not going to circle back around to land if I don't have the runway in sight at MDA on the glide slope. I'm going missed.

Well, the guy who found himself in this situation didn't intend to fly in a circle around the field to re-line-up on the runway!

No, he did just like you said. But the clearance he was given was "cleared for the ILS 21 circle-to-land 21."

 

[Skybusdriver]

Wouldn't it be simpler for the approaches to just be NOTAMED with higher straight-in minimunms? They do that kind of thing all the time for other approaches.

 

[Northern Lights]

The main one that comes to mind is Aspen (ASE).

This months Flying magazine has a write up about the March 2001 Gulfstream crash at ASE.

Seems like one of the factors was the wording of the origional NOTAM prohibiting circiling approaches at night. Since the approach only had circling mins that basically prevented the approach.

After the accident, the notam was reissued with clearer language.

 

[avbug]

Yeah, they had to do that for those that can't read the AIM.