dylan_22 wrote:
(And, although very precise, the LPV is still a non-precision approach)
It isn’t. That is a very old view.
Well, I only know what the FAA writes. (FAA Aeronautical Manual, December 2016)
1. A class of approach procedures which provide vertical guidance, but which do not meet the ICAO Annex 10 requirements for precision approaches has been developed to support satellite navigation use for aviation applications worldwide. These procedures are not precision and are referred to as Approach with Vertical Guidance (APV), are defined in ICAO Annex 6, and include approaches such as the LNAV/VNAV and localizer performance with vertical guidance (LPV). These approaches provide vertical guidance, but do not meet the more stringent standards of a precision approach. Properly certified WAAS receivers will be able to fly to LPV minima and LNAV/VNAV minima, using a WAAS electronic glide path, which eliminates the errors that can be introduced by using Barometric altimetry.
(I am aware that the minima are the same on LPVs as on ILS approaches, but I still think that legally LPV and LNAV/VNAV are no precision approaches)
So what legal or practical difference does that make? You can use them to satisfy the checkride precision approach requirement.
I know that an LPV approach is just as precise (or more precise) than any ILS, I am just saying that legally and by definition of the FAA it is not a precision approach.
Yes, it meets the checkride’s precision requirement. But in the theory test you’d have to check the “non-precision approach” box.
I personally always fly the LPV when it’s available, and I feel safer too.
Dylan, why is it not a precision approach? Because in ICAO terms no satellite approach can be precision. It is completely irrelevant.
The original LPV approaches were LPV250 and are non-precision. However the latest LPV200 versions are classified as Precision approaches:
https://www.gsa.europa.eu/news/first-egnos-lpv-200-approach-implemented-charles-de-gaulle-airport
i would love to see a sketch, too. Really curious how these different criteria play out, and if it makes some sense after all…
All i am saying is that the FAA calls LPV a non-precision approach, because that’s what they say in the AIM.
I do not know the reasons.
Part-NCO defines LPV-200 as a Cat I-approach, whereas the “traditional” LPV with DH = 250 ft or higher is called an APV-approach (APV = approach with vertical guidance). That distinction is essential because there are different rules (guidance actually) e.g. for determining RVR requirements.
It seems there is no mention at all in Part-NCO of “precision approach”, only “Cat I” and “APV” is used.
However, LPVs (all flavours) are “3D-operations” just like the ILS, whereas RNAV (even the ones with advisory guidance, i.e. “LNAV+V”) are “2D-operations”.
I believe there is an ICAO/EASA/FAA committee somewhere busy determining “how do we make this approach category business as confusing as possible for the pilots”.
huv wrote:
I believe there is an ICAO/EASA/FAA committee somewhere busy determining “how do we make this approach category business as confusing as possible for the pilots”.
I sat in such a committee yesterday. Everyone has an aspiration to make it as simple as possible to understand. Unfortunately, everyone has their own way of doing just that… :)
However, LPVs (all flavours) are “3D-operations” just like the ILS, whereas RNAV (even the ones with advisory guidance, i.e. “LNAV+V”) are “2D-operations”.
No, an RNP APCH flown to LNAV minima using a LNAV+V system like Garmin provides is a 3D operation.
