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PhotoPilot

PhotoPilot

New Member
The GNS 430 manual states that a full ILS procedure should be flown using the GPS until the procedure turn inbound. AC 90-94 states that, with a few caveats, GPS may be used in lieu of lateral navigation on any approach *except* LOC, SDF, and LDA. Since the outbound course is based on a LOC backcourse on most ILS approaches, I'm trying to figure out how to justify following the recommended Garmin procedure.

I called Garmin and they say that using the primary navaid isn't required until the final approach segment . . . but they can't tell me where to find a reference to that requirement. Does anyone here have insight or (preferably) the ability to point me to the document that contains the answer?
 
PhotoPilot said:
The GNS 430 manual states that a full ILS procedure should be flown using the GPS until the procedure turn inbound. AC 90-94 states that, with a few caveats, GPS may be used in lieu of lateral navigation on any approach *except* LOC, SDF, and LDA. Since the outbound course is based on a LOC backcourse on most ILS approaches, I'm trying to figure out how to justify following the recommended Garmin procedure.

I called Garmin and they say that using the primary navaid isn't required until the final approach segment . . . but they can't tell me where to find a reference to that requirement. Does anyone here have insight or (preferably) the ability to point me to the document that contains the answer?
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I can ask my CSIP tonight!
 
PhotoPilot said:
If he has the answer, I'll buy you a LOT of beer at Network JC! :)
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Apparently you don't remember our discussion on my CSIP! :sitaware: Did Paul talk badly of my piloting skills???????
 
ComplexHiAv8r said:
Apparently you don't remember our discussion on my CSIP! :sitaware: Did Paul talk badly of my piloting skills???????
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Not yet . . . but I haven't seen him around today! ;)

Should I look forward to a good story or two? :)
 
PhotoPilot said:
Not yet . . . but I haven't seen him around today! ;)

Should I look forward to a good story or two? :)
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Check your PM.

On the Garmin, don't you have to put it in OBS mode to do the outbound and PT? It will transition direct to the ILS once to the segment no matter what direction you are going won't it? Not sure on that.

Tell them to vector you better so you dont have to do the PT?
 
My guess is that you can use it outbound because you are shooting an ILS approach not a localizer approach. Either way, if you want to track the localizer outbound just switch from gps mode.
 
unless you are shooting a WAAS approach- which you have stated you are shooting an ILS.. you must be on vloc and be tracking the localizer- not the GPS course- WHY? Well in a GPS approach what do you have to be in by .5miles of the FAF- APR mode- you will not get that on a GPS while shooting an ILS approach. That is why on the G-1000, 430, and 530 you click the enter button to activate the approach and get a prompt saying "for VFR use only as an overlay (or something to that effect)". So an ILS requires a reciever and you must use it. Otherwise anyone could shoot an ILS if filed /G even if the ILS is out of service. You also would not have a glide slope so you could only shoot it as a LOC approach, which kills the point of a precision approach.
 
higney85 said:
unless you are shooting a WAAS approach- which you have stated you are shooting an ILS.. you must be on vloc and be tracking the localizer- not the GPS course- WHY? Well in a GPS approach what do you have to be in by .5miles of the FAF- APR mode- you will not get that on a GPS while shooting an ILS approach. That is why on the G-1000, 430, and 530 you click the enter button to activate the approach and get a prompt saying "for VFR use only as an overlay (or something to that effect)". So an ILS requires a reciever and you must use it. Otherwise anyone could shoot an ILS if filed /G even if the ILS is out of service. You also would not have a glide slope so you could only shoot it as a LOC approach, which kills the point of a precision approach.
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I thought approach mode on the 430 was supposed to start 2 miles prior to the FAF, if not then go missed??????????? :confused:
 
Higney - I'm fully aware that you can't shoot an ILS with a GPS. The question isn't about coming down the pipe on the final approach segment, it's whether Garmin is correct in saying that you can legally fly the initial segment (outbound to the procedure turn) with the GPS rather than the LOC.

You're absolutely correct, Jace. The GPS should cycle from Terminal to Approach mode 2 miles before the FAF. In the case of a full procedure ILS, if you use the GPS to fly the outbound initial leg the GNS 430 will automatically switch to VLOC and align the needle with your final approach course. (That assumes that you've set the ILS CDI Capture to 'Automatic', have an EHSI or glass panel, and have intercepted the LOC 2 miles outside the FAF.)



Someone out there has to know where the written reference to the question hides! :(
 
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