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chr
1st Dec 2018, 08:57
Hi everyone

Read a lot and still confused , having reflection why FAA , EASA , ICAO can't work together and use the same acronyms etc. but it's a different story.
Most of the publications says that RNAV(GPS) is the same as RNAV(GNSS) approach - the difference is just naming.
But , having two different Jeppesen app plates , two airports in Europe - one has RNAV(GNSS) label and the other RNAV(GPS)
First one EPWA RNAV(GNSS) 11 (attached)
they have LPV minimums - btw. for what they stated there CAT 1 ?
they have LNAV/VNAV minimums - if your aircraft is not approved for LPV
they have LNAV minimus - if your aircraft is not approved for LNAV/VNAV or LPV
Second one EDDF RNAV(GPS)Z 07
they only have LNAV/VNAV minimums and LNAV minimus

conclusion is - if RNAV(GNSS) and RNAV(GPS) are the same , why EDDF have no LPV minimums

One more question , on EPWA plate there is EGNOS frequency added - any idea for what ?

Thanks https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/1500x2000/img_1026_949e9acf700101ed1f9acfc9e2c443eb88481128.png
https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/1500x2000/img_1025_2a24aa2321b95d50dcbdf2184b800be45e171f66.png

Sonoio
1st Dec 2018, 10:38
They’re not the same
the GNSS EGNOS in Europe/ WAAS in USA have an LPV approach because use a combination of satellites that provide lateral precision and ground base station that provides vertical precision.
the LNAV/VNAV or just LNAV use just satellites, less precise

OutsideCAS
1st Dec 2018, 11:13
GNSS is also an 'umbrella' term for many different types of satellite-based navigation solution, GPS was the American set-up.

As for the rest - agreed, shambolic situation and utter mess that helps no single person understand with a logic applied. Typically aviation. Makes you want to vomit. Lets not start on RAW TAF's, METAR's and NOTAM - Like we still need such gibberish in required information.

eckhard
1st Dec 2018, 12:19
They’re not the same
the GNSS EGNOS in Europe/ WAAS in USA have an LPV approach because use a combination of satellites that provide lateral precision and ground base station that provides vertical precision.
the LNAV/VNAV or just LNAV use just satellites, less precise

I am by no means an expert but my understanding is that the basic US-launched NavStar System (GPS) can be augmented in two ways: Space-Based Augmentation (SBAS) and Ground-Based (GBAS).

SBAS requires extra geo-stationary satellites. Over the US, these provide a Wide-Area Augmentation (WAAS) signal.
Over Europe, the SBAS is called EGNOS (European Geo-stationary Navigation Overlay System).
Over India, it is called GAGAN.

These extra satellites receive a correction signal from a master ground station, which in turn receives corrections from multiple other stations, spread over a wide area, whose position is accurately known.

The correction is broadcast from the geo-stationary satellite and is receivable over a wide area by suitably-equipped GPS aircraft systems. This accurate signal allows the application of LPV minima.

GBAS is a Local Area System (LAAS) which doesn’t require an extra satellite but uses a fixed ground station to measure any errors in the raw GPS signal and broadcasts the correction to aircraft in the vicinity. This then allows the use of a GPS Landing System (GLS) which gives the pilot guidance in a very similar way to ILS.

Although Boeing aircraft are not approved for LPV approaches, some are approved for GLS approaches. I take that to mean that they are not equipped to receive the WAAS or EGNOS signal but are equipped to receive the LAAS correction.

I don’t know about Airbus.

CL300
1st Dec 2018, 13:20
I do not want to be pedantic, but all these questions are answered during the theoretical part of the PBN.
GNSS precision is always the same, the Integrity varies hence the SBAS ( or GBAS) @Eckhard is correct on his above post.
Jeppessen has a good briefing about it, as well as Flight Safety ( for once)
Remember that you need IR-PBN endorsed for each type being flown in order to fly any of these..

pilot dude
2nd Dec 2018, 20:34
Maybe this will help a bit

https://www.boldmethod.com/learn-to-fly/navigation/what-is-the-difference-between-lpv-and-lnav-vnav-approaches/

rennaps
12th Dec 2018, 09:56
CHR: " conclusion is - if RNAV(GNSS) and RNAV(GPS) are the same , why EDDF have no LPV minimums ".

Simple really, probably no one has bothered to design an LPV approach yet.