Airline Pilot Central Forums - Intercepting the localizer at IAD

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Quote:

Originally Posted by USMCFLYR (Post 1492282)

According to this information it would not be correct for ATC to instruct you to intercept the LOC outside of the standard 18nm service volume.

This is what the Air Force taught us:

Quote:

Originally Posted by AFMAN 11-217 Vol 3 Para 1.4.10.2

The localizer course may be flown outside of the 18 nm flight-check distance if the instrument procedure depicts a greater distance or radar service is provided. If the controller clears you to intercept a localizer course, regardless of the distance from the antenna, radar service is being provided and you are expected to intercept the localizer.

I'm trying to find the equivalent statement in the FAA regulations. I'm sure it's in there, because most of the stuff in 11-217 comes from CFRs, AIM, etc.

Quote:

Originally Posted by EasternATC (Post 1493387)

The current SV limits are standards that were written in a different era of technology. Everyday, thousands of airplanes at hundreds of airports are joining localizers outside of 18 miles, and they're all tracking quite reliably.

No....much of the technology is still the same and even with the newer loc antennas or GS antenna - the SVs remain the same. Yes....100s of aircraft may be intercepting locs outside 18nm. MANY locs have ESVs outside of 18nm. You, as a pilot or controller, might very well not know if a loc, (or any other ground based NAVAID) has an ESV. One clue on the chart would be any point located outside of SSVs with DME provided from the facility - as was the case with the example of LAX Rwy 25s from earlier in the thread.

Sluggo -

Quote:

The localizer course may be flown outside of the 18 nm flight-check distance if the instrument procedure depicts a greater distance or radar service is provided. If the controller clears you to intercept a localizer course, regardless of the distance from the antenna, radar service is being provided and you are expected to intercept the localizer.

In the first bolded case - there would be an ESV if the procedure depicts a fix outside of the SV. Until I ask my co-workers for further clarification, I'll state again that in a case such as EasternATC or the OP may be describing, **technically** the aircraft would be under radar control outside of the SV while "intercepting and tracking the localizer", because **technically**, without an ESV, the localizer signal does not exist outside of the SV and signal strength and quality of the signal in space can not be guaranteed to meets minimum tolerences.

This is nothing new. It's been in 7110.65 and practiced by ATC for at least 20 years now. I was an AF instrument instructor and we always covered this during the required annual IRC (Instrument Refresher Course)....

Sluggo: 7110.65, pg 184, 4-1-2 note 3

I've asked two and got different answers.
I think the one with some ATC experience from a LONG time ago might not have the most *recent* answer, so I've asked the co-worker with recent ATC experience to contribute to the thread. He agrees with EasternATC and nfn, but has some additional explanation to pass on that I hope will add to the conversation too. Hopefully we'll see him on someday today so check back for the latest updates!

I believe Eastern ATC has it right. FAAO 7110.65 (controllers handbook) 4-1-1 specifies the limitations on navaid use. 4-1-2 allows deviation from the requirements if the controller provides radar monitoring and as (if) necessary course guidance. Further if the aircraft is equiped with /E,F,G or R (FMS/GPS/RNAV) course guidance should not be required. The only thing I will add is that the controller can't issue the approach clearance until the aircraft is established on a published portion of the approach or issues an altitude to maintain that meets MVA/terrain/procedural requirements until established on a published portion. It may be that ATC uses it that far out routinely and they know it works well enough to provide the required guidance and they are radar monitoring.

4−1−1. ALTITUDE AND DISTANCE
LIMITATIONS

When specifying a route other than an established
airway or route, do not exceed the limitations in the
table on any portion of the route which lies within

controlled airspace.

4−1−2. EXCEPTIONS

Altitude and distance limitations need not be applied
when any of the following conditions are met:

Routing is initiated by ATC or requested by the
pilot and the following is provided:

Radar monitoring.

As necessary, course guidance unless the

aircraft is /E, /F, /G, or /R equipped.

So in my opinion (which is worthless) the answer to the original question is that the clearance was appropriate. Using the box and flying white line to the localizer would have been appropriate. Once established on the "published" portion you are by default within the service volume unless the facilty is restricted/NOTAMed for some distance other than what is published and it would be appropriate at that time to transition to green needle. As always, if there is a question about a clearance, ask. If there are differing opinions within the pilot group (that never happens right?) might be a good question for training/standards.

And for USMC :eek:

Quote:

Originally Posted by Taildragger86 (Post 1491926)

The other day I was flying into iad and told to intercept the localizer close to 30 miles out. I don't fly into there that often. I simply cleaned up the fms, and intercepted in white needles. I figured that intercepting in green would have caused the autopilot to constantly turn back and forth chasing the localizer because we were so far out. My captain told me that technically we have to be in green needles in order to be legal because our instructions were "intercept the localizer." Anyone have any thoughts on the best way to do this next time it comes up with a fed on board?

or you could legally be in white that far out, with your blue needle preview as the backup. Or pilot flying in white and pnf in green as a backup.

Quote:

Originally Posted by Taildragger86 (Post 1491926)

We used to handle it like this....Green needles up for verification and HDG mode for AP. the LOC may swing back and forth but you can tweak the heading to keep you on the LOC course until you get solid reception on the LOC……that way AP doesn’t chase the swinging LOC.

Get'er done :D

Quote:

Originally Posted by Taildragger86 (Post 1491926)

Anyone have any thoughts on the best way to do this next time it comes up with a fed on board?

Don't worry about the Fed on the jumpseat. If Approach cleared you to intercept and assuming cleared you for the approach, arm the APP mode and enjoy the ride.

Ferrying a 767 into ORD once from SEA, we were 20 miles outside of SEXXY for 14R and the approach controller told us "to turn right to a heading of 120, maintain 4,000' until SEXXY, cleared for the visual to 14R, cleared to land and cleared to the ramp. Goodnight". It was 3:00 AM and that was the last transmission we heard until the engines were shut down. As for the autoflight, we left it on just for the heck of it and it did a beautiful job once the APP mode was armed.

Not a big deal and the Marine answered your technical questions.

G'Night Mates:)

There was a very tragic and infamous crash of an airliner decades ago that was cleared, late at night, not by the approach controller, but by an enroute controller for an instrument approach some 40 miles from the airport.

It is why the NASA aviation reporting system, in part, exists today.

Why the splitting of hairs on this. Depending on your aircraft equipment and/or ops specs it is perfectly legal to use the fms in lieu of the localizer until you reach the FAF. Especially, if you are told to intercept LOC 20+ miles out. The guy that had the captain who demanded actual localizer capture was not correct, but since he was captain....