N

N999BT

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Maybe some of you more experienced instrument pilots can chime in here. In its infinite wisdom the FAA has decided to change the approaches at my home airport (KCOE) to require either DME or ADF. I don't think I can legally fly an instrument approach into Coeur d'Alene anymore. The old ILS 5 approach is now the ILS or LOC/DME RWY 5, there is a RNAV (GPS) RWY 5, VOR RWY 5, and VOR/DME RWY 1. The ILS approach has no way to identify the FAF other than DME, the VOR 5 approach has DME or ADF required, the VOR/DME RWY 1 requires DME, and of course the others require a certified GPS.

So, can I legally fly the ILS approach using a handheld GPS for DME? I currently have an SL-30 nav/com and a 496 for navigation and GS, along with a backup 195.
 
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Nope. Actually, it's my understanding that you can't even use a panel mounted IFR GPS to substitute for DME; if the name of the approach contains the letters DME then you actually need DME to fly it. Of course, I'm far from an expert on this - I'm currently studying for my instrument written....
 
morlino said:
Nope.
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Agreed.
morlino said:
Actually, it's my understanding that you can't even use a panel mounted IFR GPS to substitute for DME; if the name of the approach contains the letters DME then you actually need DME to fly it. Of course, I'm far from an expert on this - I'm currently studying for my instrument written....
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I disagree here. You need the stated equipment (DME) if it is in the approach Title. Otherwise, you may substitute IFR GPS if the position, fix, or whatever is pulled from the database. Example: If the approach is a VOR/DME approach title, you need both. If it is just titled VOR approach, but has available fixes in it that are based on DME or NDB or whatever, you may substitute IFR GPS for those points if you load them from the database. Clear as mud now I'm sure :).

Yeah, it looks like you are out of luck without DME or IFR GPS.
 
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Sorry

In a word...no. It isn't legal. Like many things in aviation it may be safe but it isn't necessarily legal. As a CFI I usually find myself saying the opposite "just because it's legal, doesn't mean it's safe". This is different in my opinion. I've flown behind many crappy DMEs but rarely has my GPS given me a concern.

Another consideration... I don't think it would even be an issue unless there was an accident. At which time, your DME will probably be the least of your concerns.
 
scard said:
Otherwise, you may substitute IFR GPS if the position, fix, or whatever is pulled from the database. Clear as mud now I'm sure :).

Yeah, it looks like you are out of luck without DME or IFR GPS.
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I hate to jump in with a "me too", I totally agree with Scott here, as long as the fix referenced in the DME portion of the approach is pulled from the database of the IFR GPS, and not a waypoint which has been added by you, yes, the IFR GPS can be used in lieu of DME.

Sorry, the 496 cannot be legally substituted and can only be referenced for situational awareness.
 
Yeah, clear as mud

scard said:
morlino said:
Nope. Actually, it's my understanding that you can't even use a panel mounted IFR GPS to substitute for DME; if the name of the approach contains the letters DME then you actually need DME to fly it.
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I disagree here. You need the stated equipment (DME) if it is in the approach Title. Otherwise, you may substitute IFR GPS if the position, fix, or whatever is pulled from the database. Example: If the approach is a VOR/DME approach title, you need both. If it is just titled VOR approach, but has available fixes in it that are based on DME or NDB or whatever, you may substitute IFR GPS for those points if you load them from the database. Clear as mud now I'm sure :).
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Actually, you said what I was trying to say. If the approach plate says DME in big bold letters in the upper right corner then you need it. If I didn't need to write code I would pop the semicolon key off my keyboard:eek:
 
morlino said:
Actually, you said what I was trying to say. If the approach plate says DME in big bold letters in the upper right corner then you need it. If I didn't need to write code I would pop the semicolon key off my keyboard:eek:
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Roger. Now that I read again, I agree, you were on the right track. I think too many of us (me included) have written too much code such that we stop at the semicolon :).
 
Can substitute GPS but handheld is a problem !

AOPA pushed this through a long time ago.

Effective July 16, 1998, pilots may substitute IFR-certified GPS receivers for DME and ADF avionics for all operations except NDB approaches without a GPS overlay. GPS can be used in lieu of DME and ADF on all localizer-type approaches as well as VOR/DME approaches, including when charted NDB or DME transmitters are temporarily out of service. It also clarifies that IFR GPS satisfies the requirement for DME at and above Flight Level 240 specified in FAR 91.205(e). This approval represents a major step toward removing the need to retain DME or ADF in our cockpits for any reason.

Handheld is still a problem.

Bill S
7a finishing
 
That's interesting Bill. After some searching I found this link to an AOPA page that has the information you mentioned.

Anyway, it seems to contradict what I (and apparently other people) learned in ground school. I'd be happier if I could find some mention of it in FAR 91 Subpart C or 1-1-19 of the AIM. Is it there and I just don't see it?
 
You just don't see it. It is in 1-1-19, sub paragraph f. Use of GPS in lieu of ADF and DME. My AIM is a little old, 2007, but I don't think the location has changed.

Jerry
N84JE RV-8 325 hrs doing second condition inspection.

morlino said:
That's interesting Bill. After some searching I found this link to an AOPA page that has the information you mentioned.

Anyway, it seems to contradict what I (and apparently other people) learned in ground school. I'd be happier if I could find some mention of it in FAR 91 Subpart C or 1-1-19 of the AIM. Is it there and I just don't see it?
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It's different now

In the 2009 AIM 1-1-19(f) is "Equipment and Database Requirements."

Current online version is here: http://www.faa.gov/airports_airtraffic/air_traffic/publications/atpubs/aim/Chap1/aim0101.html

In the printed 2009 version, there are no vertical black lines next to any of the text in 1-1-19. So this must have changed in 2008.

Paragraph g seems to be where the answer is:

g. GPS Approach Procedures

As the production of stand-alone GPS approaches has progressed, many of the original overlay approaches have been replaced with stand-alone procedures specifically designed for use by GPS systems. The title of the remaining GPS overlay procedures has been revised on the approach chart to "or GPS" (e.g., VOR or GPS RWY 24). Therefore, all the approaches that can be used by GPS now contain "GPS" in the title (e.g., "VOR or GPS RWY 24," "GPS RWY 24," or "RNAV (GPS) RWY 24"). During these GPS approaches, underlying ground-based NAVAIDs are not required to be operational and associated aircraft avionics need not be installed, operational, turned on or monitored (monitoring of the underlying approach is suggested when equipment is available and functional). Existing overlay approaches may be requested using the GPS title, such as "GPS RWY 24" for the VOR or GPS RWY 24.

NOTE-
Any required alternate airport must have an approved instrument approach procedure other than GPS that is anticipated to be operational and available at the estimated time of arrival, and which the aircraft is equipped to fly.
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Going back to the original posters questions referencing an approach listed as DME only to identify the FAF. As long as the FAF is in an approach certified GPS's data base, can the GPS still be used to identify that FAF in lieu of DME. I'm not talking overlay, simply being able to shoot a VOR/DME approach using the GPS in lieu of DME only. Are we confusing overlay with in lieu of? or is it just me confused now:confused:
 
When I learned me my IFR, I found a AC that specifically addressed these uses of GPS in IFR. And found that I can use GPS readouts of position for DME. Since my SL30 supports that off the gps input with DST feature. I use it regularly. GPS position is from a GX60.

What APPROACHES can be flown is a function of if you can load it up in the GPS. If the approach isn't in the GPS's database or it says "for reference only" (Garmin twist...) then you CAN'T fly it without the base equipment. Simple.
 
Stephen is correct. You will not see the "GPS in lieu of DME" in the AIM because it came out as an Advisory Circular (AC 90-94).
http://www.aopa.org/whatsnew/air_traffic/gps_in_lieu.html

Also, you will not see many new approaches with GPS in the name as RNAV will cover both GPS and previous (Area navigation) RNAV solutions. Commercial operators with (very expensive) RNAV equipment lobbied for this since it allows them to fly the new approaches with their legacy RNAV equipment. Revised GPS approaches will be renamed to RNAV approaches.
 
I was at an AOPA ASF meeting in Cincinnati and we were discussing handheld GPS's. According to the AOPA representative, you can use a handheld GPS to fly IFR enroute (as in getting directs) as long as you're in a radar environment and are in 'radar contact' with ATC. If you loose radar contact, you must navigate with whatever IFR approved navigation equipment you have. I don't think this is the case in the approach phase however when using GPS as a substitute for DME. In many cases, DME is used as a step down or allows lower minimums. In any case, accuracy is much more important and GPS substitution probably means approach certified GPS information only, not handheld GPS info.

Scott
 
Well ...

Instruction is one thing but if I start the approach I'm using everything I have to complete it successfully. I had more written in here but it could be construed as inflamatory and it is pointless to get into that.

Bob Axsom
 
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