In the US my instructors put emphasis on me saying “GPS 27” and not “RNAV 27”, because there were other RNAV approaches (based on DME/DME) and people might confuse them.
Yesterday, flying in Germany, I was calling the approach GPS and got corrected. I am supposed to call it RNAV. GPS were an American thing and the approach were supported by EGNOS and it may be GLONASS as well. RNAV is a family of approaches and therefore RNAV is the correct name. The plate says “RNAV (GPS)” and then it mentions the EGNOS channel ID.
I also learned that the minimums for LPV were coming down every month a bit. In the particular case (EDTY RWY 10) the LPV still had higher minimums than the LNAV variants.
I am a bit confused. I did hear others using the term RNAV as well. Nobody called it GPS.
Nobody called it GPS.
Correct. And the name of the approach is given on the approach plate. You should refer to it exactly as written there. No confusion through imprecise terminology in safety critical areas.
NCYankee will be here soon with a definitive response but I think GPS is the US term and RNAV is the European term.
then it mentions the EGNOS channel ID
Who thought of that? At this rate they will be printing the glideslope frequency on the ILS plates! Was that a Jepp plate, or some national CAA monster?
The plate says “RNAV (GPS)”…
This means that a perfect controller will clear you for an “RNAV GPS approach”. Many of them actually do, some say “RNAV approach”. But never “GPS approach”.
… and then it mentions the EGNOS channel ID.
The “channel ID” is a means of crosschecking that the correct procedure for the LPV approach was called up from the database. In reality, there are no “channels” involved. On some receivers (Garmin GNS…) you can select the procedure also via it’s channel ID. This can save a few turns of the knob sometimes.
“GPS” used to be used in two ways in the US. The first, which is still used, is for GPS overlays on conventional-navaid approaches, for example “VOR/DME or GPS A”. You can request and be cleared for that approach as “GPS A”, in which case you can fly it without a VOR or DME on board.
The second use, which is being phased out (since about 2000, as approaches are being revised), is for standalone GPS approaches. These used to be called “GPS” and are now called “RNAV (GPS)” instead. FAA Order 7110.65 Sec. 4-8-1 says “Approach name items contained within parenthesis; e.g., RNAV (GPS) Rwy 04, are not included in approach clearance phraseology.” So that sounds consistent with the European phraseology, but I’ve never flown in Europe (something that I can hopefully change one day).
Was that a Jepp plate, or some national CAA monster?
It was a Jeppesen plate. I just double checked with the plates that I was using in the US and they too say “RNAV (GPS) RWY xxx”.
What I notice at the moment – and I have to admit it doesn’t feel very good – is that in the US a lot of things are done differently in practice than is written in the books. @jmuelmen quotes FAA Order 7110.65 Sec. 4-8-1. Based on that my US instructors and the US approach controllers are all wrong. I swear I never heard the word RNAV a single time …
The other thing that does bug me a bit is the use of “for”. At Kennedy they were all using “3000 for 6000” instead of “passing/leaving 3000 climbing 6000” and before the checkride I was told to do the same. The examiner did like it. So….???
In the very end I do as the Romans do when in Rome but still… I am with @achima:
No confusion through imprecise terminology in safety critical areas.
To complicate matters further, chart titles will be changed over the next decade.
Currently, some states (e.g. the UK ) call approaches “RNAV (GNSS) RWY xx”, others (e.g. Germany) “RNAV (GPS) RWY xx”.
By 2022, all charts have to be retitled “RNP RWY xx” to indicate that the PBN specification “RNP APCH” is required.
However, I can’t find any relevant ICAO phraseology guidance.
The vast majority of approaches using GPS have transitioned to RNAV (GPS) in the US. Originally there were no GPS approaches in the US and to introduce the capability of GPS into the US, overlays of existing VOR and NDB approaches were implemented. These had the title like “VOR or GPS” and could be flown with either type of equipment. Then GPS stand alone procedures were developed and these had the title of GPS. As time moved on, the GPS approach specifications were refined and named RNAV. To distinguish procedures that used a rho-theta style 1980’s area navigation unit such as the KNS80 with the ones using GPS, the (GPS) was used to specify the navigation sensor from the rho-theta (VOR/DME) equipment. Over time almost all of the overlay approaches (or GPS), and the RNAV (VOR/DME) and GPS standalone procedures have been decommissioned as they were replaced by RNAV (GPS). For some it is hard to break old habits and many still refer to the RNAV (GPS) procedures as GPS, but over time this will go away. The proper term is the one printed on the chart without the name in the parenthesis, but at least here in the US, everyone knows what is meant if the procedure is called GPS. At last count there are 133 procedures left with GPS as the title, 8 with the title of RNAV (VOR/DME), and 13,068 with RNAV (GPS) in the title although many of these are included on the same approach chart (LNAV, LNAV/VNAV, LPV). A procedure must have either a LPV or LP in the title to consider it a SBAS procedure (WAAS or EGNOS). These procedures are assigned a channel number that is a 5 digit decimal value that can be used to identify the approach. Even though the capability exists in WAAS GPS units to select an SBAS approach by entering the channel number, very few use this capability or for that matter are even aware that it can be done.
By and large the airlines don’t use the RNAV (GPS) procedures, they use approaches based on RNP for lateral guidance and Baro VNAV for vertical guidance from their FMS. These procedures are named RNAV (RNP) and they all require authorization from the FAA for both the equipment and pilots. We in general aviation can’t fly these procedures and they are not included in our WAAS GPS database.
RANT ON
So now ICAO wants to adopt a totally new naming convention using PBN terminology. We already switched to RNAV and are just getting used to it, now we have to learn a totally new procedure naming convention. Forget about it, it won’t happen in the US. This is one of my pet peeves with ICAO. The US invents and deploys the technology. US aviation adopts the new technology. ICAO says our names we call things are all wrong and we need to change. Only then does the rest of the world start to implement the technology. So how many LPV with a DH of 200 feet exist outside of the US? As of April 3, 2014, there are 3,402 Wide Area Augmentation System (WAAS) Localizer Performance with Vertical guidance (LPV) approach procedures serving 1675 airports. Of the LPV procedures the majority have a DH around 250 feet and 856 have a DH of 200 feet. Currently, there are also 538 Localizer Performance (LP) approach procedures in the U.S. serving 392 airports.
RANT OFF
I think this RNAV/PRNAV/RNP stuff is a massive job creation scheme for people who have been out of the loop for too long to even get a job as an ISO9000 vendor compliance policy manager in the toilet paper procurement division of their national CAA.
The bottom fell out of the navigation market when GPS came in, but if extraterrestrial intelligence was ever proved, the pope is hardly going to jump out of the window. He will instead assemble a team to re-focus policy so they can continue to reach out to their partners.
I believe my US instructor was referring to RNAV (RNP) when she explained that I should say GPS instead of RNAV on the radio.
