portable gps = DME

Morgan3820

Morgan3820

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Hoping to verify something. A local CFII stated to me that the FAA has recently (<3 months) approved a portable GPS to be used in lieu of a panel mount DME. He quoted an FAR that I immediately forgot. Personally this would be huge, if true. Can anyone verify this?

What say ye Ron?
 
It is not true. Next time ask him to show you the wording in the regs or associated AC that permits such a thing.
 
jordane93 said:
I looked and couldn't find anything.
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Not surprising, since there no FAA document which says it. See the first row in AIM Table 1-1-6 -- hand-helds are not approved for any IFR navigational purpose. When the OP shows that reference to the instructor involved, I hope the OP writes down the regulation which the instructor says authorizes this so we can help the OP enlighten the instructor.
 
Yep, non panel installed, non TSOed, not likely will ever be authorized for anything other than VFR situational awareness.
 
Maybe the CFI is confusing AC 90-108, which allows a certified GPS to fly VOR/DME and NDB approaches, with using a non-certified GPS?
 
Morgan3820 said:
Hoping to verify something. A local CFII stated to me that the FAA has recently (<3 months) approved a portable GPS to be used in lieu of a panel mount DME. He quoted an FAR that I immediately forgot. Personally this would be huge, if true. Can anyone verify this?

What say ye Ron?
Click to expand...

Either you or he is confused on the "portable" part. An IFR certified GPS may be used in lieu of a DME. There is no portable that meets that criteria at this point.
 
Correct me if wrong, but it's all about the RAIM, or lack thereof, right?
 
RotorDude said:
Maybe the CFI is confusing AC 90-108, which allows a certified GPS to fly VOR/DME and NDB approaches, with using a non-certified GPS?
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Clark1961 said:
Is that really what that AC allows?
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The AC allows using certified GPS in lieu of NDB, DME and VOR for everything but the final approach course. However, AFAIK all US (and Canadian?) approaches predicated on those navaids have by now a suitable overlying GPS approach, so as long as the correct approach plate is used, they are practically all covered. But I stand to be corrected, and of course the AC speaks for itself.
 
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RotorDude said:
The AC allows using certified GPS in lieu of NDB, DME and VOR for everything but the final approach course. However, AFAIK all US (and Canadian?) approaches predicated on those navaids have by now a suitable overlying GPS approach, so as long as the correct approach plate is used, they are practically all covered. But I stand to be corrected, and of course the AC speaks for itself.
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I agree except with the last part. AFAIK there are very few overlay approaches left, as they have been removing overlays for many years as the number of true RNAV approaches have been growing. In fact if I'm not mistaken, the existence of a working RNAV approach is a condition for removing the overlay from a navaid-based (usually VOR or VOR/DME) approach to the same field. If an overlay exists, it's mentioned in the title of the approach (VOR OR GPS). I haven't flown an overlay approach in at least a couple of years now.

There is certainly no overlay on the VOR/DME 35 at KMPV. There used to be a VOR OR GPS-A approach at KVLL, but they removed the overlay -- at about the same time they let the VOR the approach was based off of go permanently OTS too, leaving a permanently unflyable approach still on the books (yep, it's the FAA, what they do doesn't have to make sense).
 
azure said:
I agree except with the last part. AFAIK there are very few overlay approaches left, as they have been removing overlays for many years as the number of true RNAV approaches have been growing. In fact if I'm not mistaken, the existence of a working RNAV approach is a condition for removing the overlay from a navaid-based (usually VOR or VOR/DME) approach to the same field. If an overlay exists, it's mentioned in the title of the approach (VOR OR GPS). I haven't flown an overlay approach in at least a couple of years now.

There is certainly no overlay on the VOR/DME 35 at KMPV. There used to be a VOR OR GPS-A approach at KVLL, but they removed the overlay -- at about the same time they let the VOR the approach was based off of go permanently OTS too, leaving a permanently unflyable approach still on the books (yep, it's the FAA, what they do doesn't have to make sense).
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I agree. I have flown "overlay" approaches in Canada recently, so they seem to be a bit behind up there, but in general once there is a "pure" GPS approach, the overlay version is replaced by it.
 
Ron Levy said:
Not surprising, since there no FAA document which says it. See the first row in AIM Table 1-1-6 -- hand-helds are not approved for any IFR navigational purpose. When the OP shows that reference to the instructor involved, I hope the OP writes down the regulation which the instructor says authorizes this so we can help the OP enlighten the instructor.
Click to expand...

FWIW, Garmin portables are not designed or manufactured by their avionics department. The portables are considered to be a consumer product, no different than the units folks mount in their cars.

No alerting, no integrity, no nothing.
 
RotorDude said:
I agree. I have flown "overlay" approaches in Canada recently, so they seem to be a bit behind up there, but in general once there is a "pure" GPS approach, the overlay version is replaced by it.
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We still have some overlay approaches around SoCal.

KEMT
KSMO
KVNY
KPOC
 
RotorDude said:
The AC allows using certified GPS in lieu of NDB, DME and VOR for everything but the final approach course. However, AFAIK all US (and Canadian?) approaches predicated on those navaids have by now a suitable overlying GPS approach, so as long as the correct approach plate is used, they are practically all covered. But I stand to be corrected, and of course the AC speaks for itself.
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That AC also authorizes IFR GPS instead of DME for the final approach segment of any IAP.
 
aterpster said:
That AC also authorizes IFR GPS instead of DME for the final approach segment of any IAP.
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Yes. The only thing the AC does not allow is using GPS in lieu of VOR or NDB for "pure" (not the overlay version) VOR or NDB based final approach segments (and ILS/Localizer, but that's a separate issue).
 
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As Mr Nixon used to say, "We could do that, but it would be wrong".
 
aterpster said:
FWIW, Garmin portables are not designed or manufactured by their avionics department. The portables are considered to be a consumer product, no different than the units folks mount in their cars.

No alerting, no integrity, no nothing.
Click to expand...


In regards to Garmin's portables, are you talking about the hardware, software, or both?
 
aterpster said:
That AC also authorizes IFR GPS instead of DME for the final approach segment of any IAP.
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Not quite any approach -- it does not authorize GPS in lieu of DME for lateral guidance on the final segment of the approach. See paragraph 8 in that AC:

b. Substitution on a Final Approach Segment.​
Substitution for the NAVAID (for​

example, a VOR or NDB ) providing lateral guidance for the final approach segment.​
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RotorDude said:
Yes. The only thing the AC does not allow is using GPS in lieu of VOR or NDB for "pure" (not the overlay version) VOR or NDB based final approach segments (and ILS/Localizer, but that's a separate issue).
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VOR and NDB are only two examples in that AC, not an exhaustive list, so an approach with a DME arc for the final segment is also covered by that prohibition. Of course, I only know of two such approaches in the USA, but for those two, you need a real DME on board and operating properly.
http://155.178.201.160/d-tpp/1411/05222VDTZ15.PDF
http://155.178.201.160/d-tpp/1411/00639VDT10.PDF
 
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Ron Levy said:
Not quite any approach -- it does not authorize GPS in lieu of DME for lateral guidance on the final segment of the approach. See paragraph 8 in that AC:
VOR and NDB are only two examples in that AC, not an exhaustive list, so an approach with a DME arc for the final segment is also covered by that prohibition. Of course, I only know of two such approaches in the USA, but for those two, you need a real DME on board and operating properly.
http://155.178.201.160/d-tpp/1411/05222VDTZ15.PDF
http://155.178.201.160/d-tpp/1411/00639VDT10.PDF
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It seems in both cases the RNAV mins for the same runways are much lower, so not a big loss.
 
Ron Levy said:
Not quite any approach -- it does not authorize GPS in lieu of DME for lateral guidance on the final segment of the approach. See paragraph 8 in that AC:
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Believe me, I understand the AC. I guess I failed to consider the two oddball DME ARC approaches that no one seriously uses.

So far as I know, no other country has such asinine IAPs.
 
bfergie10 said:
In regards to Garmin's portables, are you talking about the hardware, software, or both?
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Both.

The software does have most of the aviation waypoints, but not in any semblance of a format that meets aviation specifications.
 
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