LDA w/Glideslope

[CRJCptn]

I worded my last statement badly. I sould have said manuvering at minimums, not final. sorry...

 

[Amish RakeFight]

Perhaps it has been changed, but I affirmatively recall reading in the AIM a long while ago that the LDA/GS is NOT considered a precision approach.

 

[AC560]

Where this has become relevant from my perspective is that WAAS allows for GPS only airports to be alternates. So if you are part 91 it makes a difference as to which it is for alternate minimums (600/2 or 800/2).

AIM 1-1-20
(a) Due to initial system limitation, there are certain restrictions on WAAS operations. Pilots may plan to use any instrument approach authorized for use with WAAS avionics at a required alternate. However, when using WAAS at an alternate airport, flight planning must be based on flying the RNAV (GPS) LNAV minima line, or minima on a GPS approach procedure, or conventional approach procedure with "or GPS" in the title. Code of Federal Regulation (CFR) Part 91 nonprecision weather requirements must be used for planning. Upon arrival at an alternate, when the WAAS navigation system indicates that LNAV/VNAV or LPV service is available, then vertical guidance may be used to complete the approach using the displayed level of service. The FAA has begun removing the

NA (Alternate Minimums Not Authorized) symbol from select RNAV (GPS) and GPS approach procedures so they may be used by approach approved WAAS receivers at alternate airports. Some approach procedures will still require the

NA for other reasons, such as no weather reporting, so it cannot be removed from all procedures. Since every procedure must be individually evaluated, removal of the

NA from RNAV (GPS) and GPS procedures will take some time.

So whatever it is classified as it would seem to indicate that it needs to be considered as non-precision for planning purposes.

 

[avbug]

WAAS has nothing to do with an LDA approach with a glideslope. What are you talking about?

 

[AC560]

WAAS has nothing to do with an LDA approach with a glideslope. What are you talking about?

No but whether a LDA approach with a glide slope is precision or non-precision is necessary to know to determine if an airports weather is suitable for use as an alternate. This is especially true when the airport is only served by a GPS approach (which WAAS allows for).

I can't really think of any other reason why you would care if it is precision or non-precision (aside from taking the requirements of the instrument PTS). The relevant AIM section shows that for alternate planning you consider non-precision which means 800/2.

 

[avbug]

It's a common inteview question.

 

[AC560]

It's a common inteview question.

To which there is no definitive answer, but it is also a practical concern which if somebody isn't sure of the answer could cause them a problem.

Precision approaches also I will add to the discussion require precision markings on the runways and specific lighting. I don't believe that any of the GPS approaches require any special markings or lighting.

 

[avbug]

To which there is no definitive answer,

No, there certainly is a difinitive answer, and it's already been provided. What there is not is room for discussion or debate; the matter is clear.

 

[paulsalem]

No, there certainly is a difinitive answer, and it's already been provided. What there is not is room for discussion or debate; the matter is clear.

I disagree bug. FAR 1.1 gives one answer. The AIM gives another answer, and 121 OpSpecs give a 3rd answer.

 

[avbug]

Operations specifications are irrelevant, as previously discussed. They do not define the regulation.

14 CFR 1.1 and the AIM don't disagree. The AIM merely clarifies the definition as provided in Part 1.1.

For the purposes of the regulation, 1.1 is difinitive and applicable. This includes the application of regulation pertaining to the selection of an alternate, etc. The AIM serves to expand on that, but in no case replaces the regulation, nor is the AIM regulatory in any respect.

What one's operations specifications, general operations manual, fortune cookie card, horoscope, or underwear label has to say does not replace the regulation, count for regulation, or change what is stated in the regulation.

 

[paulsalem]

Operations specifications are irrelevant, as previously discussed. They do not define the regulation.

14 CFR 1.1 and the AIM don't disagree. The AIM merely clarifies the definition as provided in Part 1.1.

For the purposes of the regulation, 1.1 is difinitive and applicable. This includes the application of regulation pertaining to the selection of an alternate, etc. The AIM serves to expand on that, but in no case replaces the regulation, nor is the AIM regulatory in any respect.
.

So you agree that 1.1 defines it as a precision approach? And that the AIM lists it as a APV?

 

[AC560]

No, there certainly is a difinitive answer, and it's already been provided. What there is not is room for discussion or debate; the matter is clear.

We will just agree to disagree on that. The only matter of relevance for precision/non-precision is flight planning and in that regard it counts clearly as non-precision (or do you debate that as well).

 

[pilotyip]

Op Spec C52 Inst Approach with Vertical Guidance (APV) other than ILS or MLS
LDA/w GS, LDA PRM, LDA PRM DME; SDF/w GS, LOC BC/w GS

 

[avbug]

Once again for those just tuning in...the opspec is irrelevant.

 

[pilotyip]

How come?

Once again for those just tuning in...the opspec is irrelevant.

Why is anything in my GOM irrelevant?