Is an LPV a precision approach?

[wheightonwheels]

There seem to be different opinions regarding whether an LPV approach to 200' minimums is a Precision Approach or a Non-Precision Approach. Of course, no credit may be taken for LPV or LP lines of minima with regards to alternate aerodrome weather minima requirements (but that's not the question).

Is it stated anywhere that an LPV to 200’ minimums is not considered a precision approach? I have not been able to find this in the CARs, AIM, CAP GEN, or any NAV CANADA circular.

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There's a great article by the Director of Operational Safety at NAV CANADA. He explains how both ILS and LPV approaches provide geometric vertical guidance. He also says, "with the advent of RNAV, the precision/non-precision line is very blurry."

https://tc.canada.ca/en/aviation/public ... -challenge

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I see that ICAO Annex 6 [RD-3], provides new definitions for Approach Procedure with Vertical guidance (APV) as well as for the Precision Approach (PA) procedure. This indicates that an LPV with 200' mins is a precision approach.

“Approach procedure with vertical guidance (APV). A performance-based navigation (PBN) instrument approach procedure designed for 3D instrument approach operations Type A.”

“Precision approach (PA) procedure. An instrument approach procedure based on navigation systems (ILS, MLS, GLS, and SBAS Cat I) designed for 3D instrument approach operations Type A or B.”

Therefore, SBAS is an enabler for both approach procedures with vertical guidance (APV) and for precision approach (PA) procedures that can be based on the SBAS navigation system.

The types of instrument approach operations can be Type A and Type B, defined in ICAO Annex 6 [RD-3] as follows:

“Instrument approach operations shall be classified based on the designed lowest operating minima below which an approach operation shall only be continued with the required visual reference as follows:

a) Type A: a minimum descent height or decision height at or above 75 m (250 ft); and
b) Type B: a decision height below 75 m (250 ft). Type B instrument approach operations are categorized as:

1) Category I (CAT I): a decision height not lower than 60 m (200 ft) and with either a visibility not less than 800 m or a runway visual range not less than 550 m;”

Consequently, an operation making use of the LPV-200 capability is a precision approach procedure which corresponds to a 3D instrument approach operation (since it is based on both horizontal and vertical guidance) of:

Type A if DH ≥ 250 ft
Type B if DH < 250 ft

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Final Question:

If someone classifies an LPV as Precision or Non-Precision does it really matter? As long as all rules are followed. Are there any factors that actually matter when classifying an LPV as precision or non-precision?

[scabbydoo]

There seem to be different opinions regarding whether an LPV approach to 200' minimums is a Precision Approach or a Non-Precision Approach. Of course, no credit may be taken for LPV or LP lines of minima with regards to alternate aerodrome weather minima requirements (but that's not the question).

Is it stated anywhere that an LPV to 200’ minimums is not considered a precision approach? I have not been able to find this in the CARs, AIM, CAP GEN, or any NAV CANADA circular.

------------------------------------------------------------

There's a great article by the Director of Operational Safety at NAV CANADA. He explains how both ILS and LPV approaches provide geometric vertical guidance. He also says, "with the advent of RNAV, the precision/non-precision line is very blurry."

https://tc.canada.ca/en/aviation/public ... -challenge

------------------------------------------------------------

I see that ICAO Annex 6 [RD-3], provides new definitions for Approach Procedure with Vertical guidance (APV) as well as for the Precision Approach (PA) procedure. This indicates that an LPV with 200' mins is a precision approach.

“Approach procedure with vertical guidance (APV). A performance-based navigation (PBN) instrument approach procedure designed for 3D instrument approach operations Type A.”

“Precision approach (PA) procedure. An instrument approach procedure based on navigation systems (ILS, MLS, GLS, and SBAS Cat I) designed for 3D instrument approach operations Type A or B.”

Therefore, SBAS is an enabler for both approach procedures with vertical guidance (APV) and for precision approach (PA) procedures that can be based on the SBAS navigation system.

The types of instrument approach operations can be Type A and Type B, defined in ICAO Annex 6 [RD-3] as follows:

“Instrument approach operations shall be classified based on the designed lowest operating minima below which an approach operation shall only be continued with the required visual reference as follows:

a) Type A: a minimum descent height or decision height at or above 75 m (250 ft); and
b) Type B: a decision height below 75 m (250 ft). Type B instrument approach operations are categorized as:

1) Category I (CAT I): a decision height not lower than 60 m (200 ft) and with either a visibility not less than 800 m or a runway visual range not less than 550 m;”

Consequently, an operation making use of the LPV-200 capability is a precision approach procedure which corresponds to a 3D instrument approach operation (since it is based on both horizontal and vertical guidance) of:

Type A if DH ≥ 250 ft
Type B if DH < 250 ft

------------------------------------------------------------

Final Question:

If someone classifies an LPV as Precision or Non-Precision does it really matter? As long as all rules are followed. Are there any factors that actually matter when classifying an LPV as precision or non-precision?

It's neither a precision approach, nor NPA. It's considered an "approach procedure with vertical guidance"

[wheightonwheels]

It's neither a precision approach nor NPA. It's considered an "approach procedure with vertical guidance"

So an LPV is not a Precision Approach and not a Non-Precision Approach. So it's uncategorized? How can it be neither precision nor non-precision?

What about ICAO defining LPV with 200' mins as a Precision Approach?

And since you don't classify an LPV as Precision or Non-Precision does it really matter what you classify it as? As long as all rules are followed. Are there any factors that actually matter when classifying an LPV as precision, non-precision, or neither?

[digits_]

Are there any factors that actually matter when classifying an LPV as precision, non-precision, or neither?

There are some ops specs out there with regards to approach bans, how much you can go below the advised visibility etc. Those limits are generally different for precision approaches and non-precision approaches. It could create situations where you are banned for an ILS approach, but not for an RNAV or LPV approach with higher minima.

[88gtst]

It only really matters when it comes to filing IFR alternates whether an approach is precision or non-precision.

From a practical point of view if you can make it down to 200-250' and 1/2 mile it's as precision as I would ever expect it to be. I may be out of date with my knowledge (maybe I should work on that... ) but for the years I flew 703, the LPVs were always restricted for IFR alternate filing when flying around MB and NWO. Perhaps it's changed now? I don't know, I just fly ILS to ILS now with the flight plan dispatch gives me.

[Cliff Jumper]

https://tc.canada.ca/en/aviation/refere ... no-700-023

Quotes...

Prior to the advent of GNSS, ICAO defined only two types of approach and landing operations - precision approach (PA) and non-precision approach (NPA). It has now added a definition for APV to cover approaches that use lateral and vertical guidance, but that do not meet the requirements established for precision approach. The vertical guidance of an APV is referred to as approved vertical guidance.

and...

4.3 Localizer Performance with Vertical Guidance Minima
The LPV minima depict a DA.
NP approaches to LPV minima are a form of APV which define both a lateral and vertical path through space.
Note. At the time of writing this document, ICAO was considering the possibility of including this type of approach in the category of Precision Approach, instead of APV.

Granted, this was 2013.

[lownslow]

Within the last year I asked a TC inspector this same question. Nearly an hour of explanation later I still had no idea.

[cargocowboy]

Not sure if this helps at all, but when I did my MIFR ride a few years ago, the airport wasn't equipped with an ILS, so I did an LPV and that counted as a precision approach.

[scdriver]

Not sure if this helps at all, but when I did my MIFR ride a few years ago, the airport wasn't equipped with an ILS, so I did an LPV and that counted as a precision approach.

I believe tc and all their examiners consider an LPV to be a precision approach for that purpose, and to every effect it is absolutely a precision approach, BUT it does not meet the requirements to be technically classified as such

[sjatana]

As per the AIM COM 5.4.2:

"The LP and LNAV minima indicate an NPA, while the LNAV/VNAV and LPV minima refer to APV approaches (RNAV approaches with vertical guidance). However, the actual terms “NPA” and “APV” do not appear on the charts because they are approach categories not related to specific procedure design
criteria."

[‘Bob’]

It's neither a precision approach, nor NPA. It's considered an "approach procedure with vertical guidance"

So a precision approach.

precision approach means an instrument approach by an aircraft using azimuth and glide path information; (approche de précision)

https://laws-lois.justice.gc.ca/eng/reg ... l#h-987440

[scabbydoo]

It's neither a precision approach, nor NPA. It's considered an "approach procedure with vertical guidance"

So a precision approach.

Nah.

From ICAO:
"APV approaches terminate in a visual segment and provide for a “straight-in” landing. APV
approaches can provide a lower DA than precision approaches in certain circumstances; however an
APV approach is not a precision approach (PA)."

https://www.icao.int/APAC/Meetings/2013 ... 0Final.pdf

[fish4life]

Ops spec for 50% vis on a non-precision approach while precision approach is stuck using the 75% (no Center line lighting) would result in a LPV being allowed to conduct the approach down to 1/4 mile while the ILS is 3/8th

[sstaurus]

Which we saw at my former regional, where LPV approaches had a lower approach ban vs the ILS. IE CYQT, LPV was 1200, vs 1600 for the ILS.

[wheightonwheels]

Advisory Circular (AC) No. 700-023 states, “Approach with Vertical Guidance (APV) is an instrument approach procedure that utilizes lateral and vertical guidance that does not meet the requirements established for a precision approach.

So where are the published requirements established for a precision approach? I don't see TC listing that anywhere?

I'd be curious to see those requirements because an LPV-200 provides the same precision as an ILS. Both provide 200' mins with geometric vertical guidance. And I've seen it too flying 705, LPV has lower approach ban limits.

[bcrosby]

Somewhat related (I posted this question today on Twitter).

What is meant by the baro-vnav line here in the GAP GEN (Page 30): "Credit may be taken for VNAV/LNAV lines of minima when the aircraft is certified for barometric VNAV/LNAV".

Does this mean that using an LPV with baro-vnav is considered an PA for the purposes of IFR alternate?

[digits_]

Somewhat related (I posted this question today on Twitter).

What is meant by the baro-vnav line here in the GAP GEN (Page 30): "Credit may be taken for VNAV/LNAV lines of minima when the aircraft is certified for barometric VNAV/LNAV".

Does this mean that using an LPV with baro-vnav is considered an PA for the purposes of IFR alternate?

That you can take the minima for the VNAV/LNAV line of the approach. There can be different minima for the same approach, depending on if you fly it as an LPV, VNAV/LNAV or just as an LNAV.

[co-joe]

GPS based approaches are non precision. Doesn't matter if they are LNAV, LNAV/ VNAV, WAAS based LPV, RNP AR, IAN, or just RNAV, whereas Cat I, II, and III ILS are precision approaches.

[bcrosby]

I wasn't satisfied with everyones responses of "It's not a precision approach" with no explanation why. The full write up is on my blog, but the gist of it is:

It's not a precision approach because ICAO says so. Although an LPV approach uses geometric vertical guidance (like an ILS) and has minimums down the 200' (like an ILS) ICAO still classifies it as an "Approach with vertical guidance".

[digits_]

What ICAO says is pretty much irrelevant. It will affect the Canadian laws, but for Canadian pilots it only relevant what is written in the Canadian rules and regulations.

[photofly]

In the context of picking an alternate as required by the CARs, it seems this, from CAR101, trumps any external definition:

precision approach means an instrument approach by an aircraft using azimuth and glide path information; (approche de précision)

I note that Bob pointed that out earlier in this thread.

Why is that important? Because any enforcement action would be for some non-compliance with a regulation, and the definitions within those regulations would apply. I would very much like to see an inspector from enforcement explain to a tribunal why an LPV approach, which provides azimuth and glide path information, and clearly meets the definition in the regulations, should not count as a precision approach for any purpose where one is required by those same regulations.

[ross1]

...does a "Precision Approach" not also require specific lighting to be classified as such?

[photofly]

I think the available lighting determines the minima - there’s no real approach lighting at CYTZ and the (now withdrawn) ILS RW26 had 250’ minima but was still a precision approach.

[Transition9er2]

Here’s a question to ask in response to your question.

Are you using traditional LOC and Vertical Guidance needles and freq’s?

Or are you programming it in a box and flying the box?