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LDA/DME 25

I don't see any requirement for WAAS, or for GPS.

You will need to identify the IAF which requires NAV and DME.

Disclaimer: I don't have my Instrument rating, but I am pretty close.

Good exercise anyway.
 
If it is in the database, I believe it can be flown with the 430W. I am going to look at mine tomorrow and see if the approach is, in fact, in the database. The IAF will be a waypoint, so should not require any other nav source to identify.
 
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Sorry, I mis read that. When I first read it, I thought you were asking if the 430 was the only system that could be used to fly the approach. Just poor reading on my part.

I believe the 430 would qualify. Doesn't the 430 have the NAV radios as well, and I believe GPS can be substituted for DME.
 
Thanks guys, I could have been more clear.

Yes, let's say the only navigational equipment is a Garmin 430W, which is capable of IFR GPS and it also has a built in VOR/ILS receiver.

The DME is the crux of the question. How would you view/tune/use the I-ESJ as ILS DME (or in this case LDA DME) is different than a VOR DME.

Thanks!

-Jim
 
Your GPS should have CIPKU in its database.

Edit - sorry, thought you were looking for a way to identify the MAP. You can tune and identify the frequency the same as other localizers. The GPS will have the stepdown fixes in its database and you can use those.
 
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Hi Jim. I just flew this approach last Sunday in a Pilatus PC-12, using a Garmin GNS 480 (not a 430). As you know the 430 is more advanced than the 480 so I'm guessing the performance would be similar.

I had the 480 in GPS mode flying from VOAXA to AQULA, with 109.75 tuned in the 480's VOR/LOC field. As the autopilot turned us right to 246 over AQULA, the 480 switched itself to LOC mode and I had localizer and GS guidance. I hit approach on the autopilot and it coupled to both localizer and GS.

I had DME the whole way in from AQULA. I think your question is, was I seeing GPS DME from KEGE, or was this LOC DME from I-ESJ.

Um, I have no idea.

Don't know if this helps. In my opinion, you can shoot ANY approach with a single 430W, except of course an NDB.

Scorch
 
RV6_flyer said:
See this link. It is taking its info from the AIM. http://simfliteminnesota.blogspot.com/2007/10/substituting-gps-for-dme-and-adf.html
Click to expand...
There's some confusion in the comments at the end of that post, maybe due to the fact that the AIM has been revised on this topic over the years. Here's a link to the latest 2010 AIM section 1-2: http://www.faa.gov/air_traffic/publications/ATpubs/AIM/Chap1/aim0102.html Section 1-2-3(c) says:

Operators may use a suitable RNAV system in the following ways.

1. Determine aircraft position over or distance from a ... DME fix ...

...

These operations are allowable even when a facility is explicitly identified as required on a procedure...​

A properly installed GNS 430W is "a suitable RNAV system" according to the AC 90-100A compliance table http://www.faa.gov/about/office_org...fs/afs400/afs470/media/AC90-100compliance.xls.

So, as far as the KEGE LDA/DME 25 goes, if you are using the 109.75 localizer for lateral guidance, and are also displaying distance to the I-ESJ GPS waypoint, you should be good to go.

--Paul
 
"I had the 480 in GPS mode flying from VOAXA to AQULA, with 109.75 tuned in the 480's VOR/LOC field. As the autopilot turned us right to 246 over AQULA, the 480 switched itself to LOC mode and I had localizer and GS guidance. I hit approach on the autopilot and it coupled to both localizer and GS.
Click to expand...

Does any one know if 430 is capable of doing this, that is being in the GPS mode and once it is established on the localizer, switches itself to the VLOC mode? To the extend I know, it will only give a message to switch to VLOC and will not do it automatcially.

Thanks
 
Bavafa said:
Does any one know if 430 is capable of doing this, that is being in the GPS mode and once it is established on the localizer, switches itself to the VLOC mode? To the extend I know, it will only give a message to switch to VLOC and will not do it automatcially.
Click to expand...

Yes, a 430 (or 430W, or 530/530W) can be configured to automatically switch from GPS to VLOC when on an approach. Makes those ILS approaches a breeze. Check out the section on "Aux Pages - Setup 1 - CDI / Alarms" in the pilot's guide:

GNS 430W Pilot's Guide said:
An “auto” ILS CDI selection allows the 400W-series unit to automatically switch the external CDI from the GPS receiver to the VLOC receiver, when intercepting the final approach course. Or, select “manual” to manually switch the external CDI connection, as needed (using the CDI key).
Click to expand...

I should also mention that this also requires your EFIS or HSI to be sending back certain data to make the 430 happy, although off the top of my head I can't recall exactly what.

mcb
 
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Yes and no....

...I had that condition recently. I was shooting a GPS approach with the Loc frequency dialed in on the 430W, feeding the Dynon 100 the magenta (GPS) stripe on the HSI.

I had to push the NAV/SRC button on the HS-34 to cycle to Nav/Loc mode...it won't do it automatically, and then the Loc needle becomes green.

Personally, I wouldn't want it to switch because at times, that particular system goes down. Furthermore, you have to "Load" the desired approach to have total guidance, including MAP procedures. I had loaded the RNAV Rwy 04 approach and then activated it.

Best,
 
mburch said:
Yes, a 430 (or 430W, or 530/530W) can be configured to automatically switch from GPS to VLOC when on an approach. Makes those ILS approaches a breeze. Check out the section on "Aux Pages - Setup 1 - CDI / Alarms" in the pilot's guide:

mcb
Click to expand...

Matt,
If I understand the manual correctly, it seems it can set the "external CDI" to either GPS or VLOC. But I was refering to the source of signal that comes from the 430. In another word, can I set my 430W for an ILS approach and leave it in the GPS mode, so once the FA has been intercepted it switch itself to the VLOC.

I have used the 430W simulator and it does not do that eventhough the CDI on the setup page is set to auto , I will try it on my next flight to see if mine will switch automatically.

My GRT EIFS talk to the 430 and I can set my OBS on the 430 from the GRT so I would imagine that they are talking OK.

Thanks
 
Bavafa said:
If I understand the manual correctly, it seems it can set the "external CDI" to either GPS or VLOC. But I was refering to the source of signal that comes from the 430. In another word, can I set my 430W for an ILS approach and leave it in the GPS mode, so once the FA has been intercepted it switch itself to the VLOC.
Click to expand...

Okay... If I understand correctly, you are displaying GPS and VLOC data on an EFIS, right? If so, the EFIS needs to be smart enough to listen when the 430 tells it that it's time to switch from GPS guidance to VLOC guidance. I'm not sure if every EFIS can do this (I do know the one in my airplane can).

cheers,
mcb
 
The display is not an issue, in fact my EHSI on the EFIS will display both VLOC and GPS needle simultaneously. The issue that I can forsee is in such way...
I am on a ILS approach which has been loaded into the 430 FP, but GPS is selected as the source for navigation. If the LOC freq is on the active freq, then I will see needles for LOC/GS and the GPS for track only(GPS needle shows in different color then LOC/GS). If this is coupled to my A/P, then it will not follow the GS as long as the GPS is the source for navigation.

I am wondering if the 430W is smart enough to know that I am on a ILS approach and it will automatically select the VLOC. The 400W simulator that I have does not do that but it gives me a message to select VLOC.

Hope this makes more sense.
 
Bavafa said:
I am wondering if the 430W is smart enough to know that I am on a ILS approach and it will automatically select the VLOC.
Click to expand...

The 430 can do this, although your EFIS plays a part as well. Like I said, I'm not sure all EFISes are capable of doing this.

good luck,
mcb
 
Scorch said:
Don't know if this helps. In my opinion, you can shoot ANY approach with a single 430W, except of course an NDB.

Scorch
Click to expand...

I think that you can shoot an NDB approach with a WAAS approved unit (i.e. 430W) as long as the approach is in the database.
 
dmaib said:
I think that you can shoot an NDB approach with a WAAS approved unit (i.e. 430W) as long as the approach is in the database.
Click to expand...

Actually, no you cannot. If the IAP is not an overlay (NDB/GPS) then you need an operable ADF to fly an NDB IAP. Yes, it's in the database, and it probably gets done alot, but it's not legal. In fact when you pull up the IAP from your database and try to use it the 430 will give you a warning that the GPS cannot be used for primary guidance on this approach.

Let your conscience (and whoever is in the right seat) be your guide :rolleyes:

George
 
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I don't have the source, but I am fairly sure that I read that a WAAS approved unit did not have to have an operating ADF/NDB or VOR to shoot the underlying approach. I will see if I can find where I read that.
 
dmaib said:
I don't have the source, but I am fairly sure that I read that a WAAS approved unit did not have to have an operating ADF/NDB or VOR to shoot the underlying approach. I will see if I can find where I read that.
Click to expand...

I recently finished my checkride and during the instructions and checkride, it was made clear to me that even though a non-GPS approach is in my 430W DB and can be flown, it would not be legal to do so. This would also be the case for a LOC approach to be flown by the use of the GPS only.
 
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