Why was this section about GPS use removed from the AIM?

BenWA

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In my old 2006 AIM there is a subsection 1-1-19(f) titled "Use of GPS in lieu of ADF or DME". Sometime since then (not sure which year) the AIM was updated with that subsection omitted completely. Why was that text removed?

What FAA publication can one now refer to for information about when GPS can or cannot be used in lieu of ADF of DME for approaches, holds, etc.?

I have seen questions/uncertainties arise from this topic time and again in the various forums, and the answers always seem to be contradictory and unresolved.

For example, can one legally hold at a DME fix if the aircraft is not equipped with DME, but has an approved/certified IFR GPS? Or can one hold at an NDB or compass locator if there is no ADF, but if there is an IFR GPS?
 

BenWA

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And there it is, clear as day. Thanks. I still find it curious that they had the same table in the '06 edition but decided to hack all that detailed provisional/limitation text in the more recent versions.
 
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avbug

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BenWa, there's more.

http://www.faa.gov/air_traffic/publications/ATpubs/AIM/Chap1/aim0102.html

AIM 1-2-3 covers this in more detail:

1-2-3. Use of Suitable Area Navigation (RNAV) Systems on Conventional Procedures and Routes
a. Discussion. This paragraph sets forth policy concerning the operational use of RNAV systems for the following applications within the U.S. National Airspace System (NAS):
1. When a very-high frequency omni-directional range (VOR), DME, tactical air navigation (TACAN), VORTAC, VOR/DME, nondirectional beacon (NDB), or compass locator facility including locator outer marker and locator middle marker is out-of-service (that is, the navigation aid (navaid) information is not available); an aircraft is not equipped with an ADF or DME; or the installed ADF or DME on an aircraft is not operational. For example, if equipped with a suitable RNAV system, a pilot may hold over an out-of-service NDB. This category of use is referred to as “substitute means of navigation.”
2. When a VOR, DME, VORTAC, VOR/DME, TACAN, NDB, or compass locator facility including locator outer marker and locator middle marker is operational and the respective aircraft is equipped with operational navigation equipment that is compatible with conventional navaids. For example, if equipped with a suitable RNAV system, a pilot may fly a procedure or route based on operational VOR using RNAV equipment but not monitor the VOR. This category of use is referred to as “alternate means of navigation.”
NOTE-
1. Additional information and associated requirements are available via a 90-series Advisory Circular titled “Use of Suitable RNAV Systems on Conventional Routes and Procedures.”

2. Good planning and knowledge of your RNAV system are critical for safe and successful operations.
3. Pilots planning to use their RNAV system as a substitute means of navigation guidance in lieu of an out-of-service navaid may need to advise ATC of this intent and capability.
b. Types of RNAV Systems that Qualify as a Suitable RNAV System. When installed in accordance with appropriate airworthiness installation requirements and operated in accordance with applicable operational guidance (e.g., aircraft flight manual and Advisory Circular material), the following systems qualify as a suitable RNAV system:
1. An RNAV system with TSO-C129/ -C145/-C146 (including all revisions (AR)) equipment, installed in accordance with AC 20-138 (including AR) or AC 20-130A, and authorized for instrument flight rules (IFR) en route and terminal operations (including those systems previously qualified for “GPS in lieu of ADF or DME” operations), or
2. An RNAV system with DME/DME/IRU inputs that is compliant with the equipment provisions of AC 90-100A, U.S. Terminal and En Route Area Navigation (RNAV) Operations, for RNAV routes.
NOTE-
RNAV systems using DME/DME/IRU, without GPS/WAAS position input, may only be used as a substitute means of navigation when specifically authorized by a Notice to Airmen (NOTAM) or other FAA guidance for a specific procedure, NAVAID, or fix. The NOTAM or other FAA guidance authorizing the use of DME/DME/IRU systems will also identify any required DME facilities based on an FAA assessment of the DME navigation infrastructure.

c. Allowable Operations. Operators may use a suitable RNAV system in the following ways.
1. Determine aircraft position over or distance from a VOR (see NOTE 4 below), TACAN, NDB, compass locator, DME fix; or a named fix defined by a VOR radial, TACAN course, NDB bearing, or compass locator bearing intersecting a VOR or localizer course.
2. Navigate to or from a VOR, TACAN, NDB, or compass locator.
3. Hold over a VOR, TACAN, NDB, compass locator, or DME fix.
4. Fly an arc based upon DME.
These operations are allowable even when a facility is explicitly identified as required on a procedure (e.g., “Note ADF required”).
These operations do not include lateral navigation on localizer-based courses (including localizer back-course guidance) without reference to raw localizer data.
NOTE-
1. These allowances apply only to operations conducted within the NAS.

2.The allowances defined in paragraph c apply even when a facility is explicitly identified as required on a procedure (e.g., “Note ADF required”). These allowances do not apply to procedures that are identified as not authorized (NA) without exception by a NOTAM, as other conditions may still exist and result in a procedure not being available. For example, these allowances do not apply to a procedure associated with an expired or unsatisfactory flight inspection, or is based upon a recently decommissioned navaid.
3. Pilots may not substitute for the navigation aid providing lateral guidance for the final approach segment. This restriction does not refer to instrument approach procedures with “or GPS” in the title when using GPS or WAAS. These allowances do not apply to procedures that are identified as not authorized (NA) without exception by a NOTAM, as other conditions may still exist and result in a procedure not being available. For example, these allowances do not apply to a procedure associated with an expired or unsatisfactory flight inspection, or is based upon a recently decommissioned navaid.
4.For the purpose of paragraph c, “VOR” includes VOR, VOR/DME, and VORTAC facilities and “compass locator” includes locator outer marker and locator middle marker.
 

BenWA

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Well that answers that question. Just when I thought I had a section virtually memorized, they go and change it on me, and put it somewhere else.

Thanks again.
 
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