RNAV / GNSS approach requirements
 

Hey folks!
I'll cut straight to the chase - under JAR (respectively now EU-OPS), what are the requirements to fly an RNAV non-precision approach? A GPS approach? Is special flight crew training or even company certification necessary for a bog standard RNAV IAP? I understand that RNP (and obviously RNP-AR) approaches are a different animal, but I am mainly concerned about normal GPS approaches. There has been a lot of talk and confusion about this in my company, we are P-RNAV certified, we fly RNAV approaches in simulator, but there is talk that we are lacking approval for RNAV approaches. Please enlighten me ;)

Cheers!

Short answer:
approval required

Long answer:
happy reading :)
http://www.easa.europa.eu/agency-mea...MC%2020-27.pdf

Thanks for the link, but that document specifially refers to RNP approaches which obviously require approval. I am concerned about regular non-RNP RNAV and GPS approaches, like the ones that have replaced most NDB approaches in Europe, or new RNAV approaches in central and east Africa (i.e. HAAB etc.).

The way I understand it is that there are two type of RNAV approaches.
GNSS and RNP. You do need approval for them, training, etc.
RNP-AR is a whole different thing though.

I stand to be corrected maybe..

RNP APCH is a normal RNAV approach as you are referring to. It is labelled RNAV (GNSS/GPS) on an approach chart.

RNP-AR APCH is a RNP (normally with RF Leg after FAP). It is labelled RNAV (RNP) on an approach chart.

You will need to read up on the requirements for RNP APCH.

StbyRudder,

Going with the information provided by my company(which may be different from your regulatory body) and really and extremely short summary of a few dozen pages, here goes:

if your are PRNAV approved, as stated in the limitations section of your aircraft manual, you should be able to fly procedures that have a plain RNAV in the approach header.

RNP approaches, and ICAO really messed up here because one has nothing to do with the other, have RNAV(GNSS) in the header. If the limitation section of your airplane manual states RNP APCH approved, then you can fly RNP (RNAV(GNSS)) approaches. Depending of course on your regulatory body because training and subsequent authorization is required.

RNP AR APCH, contrary as stated earlier are RNP approaches for which additional aeroplane certification and pilot training requirements are defined! They may have lower RNP values than the standard RNP APCH value of 0.3, limitations of use should be published in your aircraft manual and training manual.

Hope this helps!

GPS usage
 

Let's bring another factor into it.
GNSS procedures require the navigation computer to use the GPS inputs provided [as such there will not be a requirement to enter a potentially incorrect QNH resulting in blunder error].
NOTE: not all in-service aircraft (like the 737) have this capability, thus are restricted to BARO-VNAV which requires higher minimums and are not authorised to fly GNSS approaches, only LNAV/VNAV using the Baro VNAV technique.

With a GPS's as part of the aircraft's navigation computers, the aircraft then requires the ANP<RNP to be within limits, the RNP being default coded by set parameters by its provider iaw minimums set by authorities depending on phase of flight (cruise, approach, final approach, etc). More detailed requirements for this capability can be found in various websites, they include but are not limited to things like 'no single failure may..." statements, basically requring dual FMS, autopilot, etc before it can be used.

The theory is extensive and very much airframe specific whether or not it can be applied to an operation.

I agree with flyburg.

RNAV is not RNP.

The header used to say RNAV (RNP) not RNAV(GPS or GNSS)

RNAV (GPS) is not the same as RNAV(RNP)

This is a very confusing an un-necessary designation for RNP. IF you have the cert for RNP, it should not be RNAV(GPS) which has a limit of RNP1.0.

RNAV RNP should be left for RNP 0.3 -0.1 with the associated equippage and training.

Its the whole crap with enroute and people not wanting to equip/train to RNP-AR.

That's not the case here. In the old days, we did GPS NPA approaches, and had an approval for such approaches (after pilot training in GNSS theory and doing 3 approaches under training).

When the RNP concept was formalised recently, our authority decided that the old GPS NPA approaches were equivalent to RNP APCH LNAV approaches ie RNP 0.3 required. The 0.3 was always the navigation performance required for our GPS NPAs anyway.

As far as training goes, the training for RNP APCH LNAV (and LNAV/VNAV [being Baro VNAV]) is the same as the old GPS NPA: theory course and 3 training approaches.

So to answer the OP's question, here you need Flight Manual authorisation and be trained in theory and 3 approaches before being authorised to conduct RNP APCH LNAV approaches.

The chart titles for our RNP APCH LNAV approaches are "RNAV-Z (GNSS) RWY 23".

The chart titles for RNP-AR approaches are "RNAV-U (RNP) RWY 23".

From what I can see of the requirements for RNP-AR, I don't blame them.

The above is the navigation specification (see PBN Manual) for RNAV(GNSS) approaches. They are currently titled as RNAV(GNSS). ICAO have an extended transition period to retitle RNAV/RNP procedures.

The concept of PBN was essentially to rationalise the number of navigation specifications and simplify the whole RNAV/RNP issue. Probably not surprising to see it going the other way. Standby for ARNP and RNP(0.3) specifications next year....

Cpt Bloggs,

Forget about the nomenclature for a minute.

The obstacle clearance areas for RNAV and RNP approach procedures are completely different in the criteria.

I see a fatal fault in blending the two (in the OP's original post)

As you have the designation 'U', it appears you are in AUS, and of course, with the much more common sense down-under, one would not expect such issues.

Enjoy!

Understand. But that's why the approvals/requirements for each are completely different, and the charts are completely different. There is no way anybody could "just fly" an RNP AR without knowing that they have to jump thru all the hoops... I would hope! :)

I think STBYRUD has a good handle on the whys and wherefores of the two approach types from what he posted with his question; he's just after what's needed for RNP APCH LNAVs.

Thanks for all the replies... Good to see that I am not the only one who thinks this might be an issue. I currently fly with Lido charts, and there is a clear distinction between RNAV (GNSS), RNAV (GPS) and RNAV (RNP)... The RNP approaches, such as LOWI 26, LOWS 33, KDCA 19/01 all carry extra remarks that authorization is required and an RNP value of 0.15 or 0.3 is given. This is obviously not the case for the non-RNP RNAV approaches at the same airport ( LOWS 15, KDCA 33... etc). Ipso facto any aircraft capable of and certified for RNAV (be it a GPS installation in a Seneca or an FMS aircraft) should be able to fly the regular RNAV (GNSS/GPS) approach. I have not been able to find any regulations to the contrary in Doc 8168 or EU-OPS... :sad:

STBYRUD,

Send you a pm, but have since done some more digging and came up with the following: there are 3 ways to designate a RNP approach(we use LIDO as well). In the header it will say:

1 RNAV(GNSS)= RNP approach
2 RNAV(GPS)= RNP approach as well ( think, but not sure, this is mainly used in The US)
3 RNAV(RNP)= RNP AR approach

So all 3 are RNP approaches! In your airplane manual it should state in the limitations section RNP APP approved and you should be authorised by your authority. for 3 there should be additional requirements.

So, no, you can't fly those unless the airplane is certified(RNP APCH in the limitation section) and authorization is granted by your authority.

Any other non precision approaches that are coded in your FMS can be flown in LNAV and VNAV(if it has a GP coded in your database but to a higher MDA than a real RNP with APV).

To give you an example, in my company, the 777 and A330 can do RNP approaches while the 747 is technically capable of RNP approaches but we have not received authorization yet to do those, in the limitation section of the airplane manual it does not state RNP APCH( it is pending, and in the mean time we are practicing them in the sim until we get approval). However, on the 747 we do al non precision approaches( LOC, VOR, NDB) in LNAV/VNAV as long as they are coded in the FMS.

Hope this helps! This goes for my company and is what we are thought but may be different in yours.

Question for you: what kind of airplane do you fly and in the limitation section of your airplane manual, what does it say in type of operation? Does it say RNP APCH approved? Mine currently says B-RNAV, P-RNAV, RNP-4, RNP-5 and RNP-10.

RNAV (GPS) is used in europe as well, at least the LIDO charts for my homebase (TXL) have them. Seems like the germans use that term instead of the more often used RNAV (GNSS).

On my type (737) the types of approved operation reads as follows:

The aircraft is eligible for the following types of operations:
• Visual Flight (VFR)
• Instrument Flight (IFR)
• Basic Area Navigation (B-RNAV/RNAV 5)
• Precision Area Navigation (P-RNAV/RNAV 1)
• Reduced Vertical Separation Minima (RVSM)
• GLS (GNSS/GBAS) CAT I
• RNAV (GNSS) Approach (RNP APCH)
• RNAV (RNP) Approach (RNP AR APCH)
• Icing Conditions
• Night Flight
• Over Water Operation
• Automatic Approach to CAT II and CAT III Weather Minima and Automatic Landing

Although it says RNAV (GNSS) there is no problem with RNAV (GPS) approaches in germany and we do fly them the same as we do the RNAV (GNSS) elsewhere.

Here, "GPS" was replaced in all the documentation with "GNSS" recently, I assume to reflect the probability that a GPS receiver would soon be receiving signals from more than the original US Navstar GPS system. As far as I can tell, there's no operational difference except that "GNSS" is harder to say! :{

Hi Denti,

Mine has some of those items as well of course, I just skipped them as they didn't pertain to the question.

You are right though (GNSS) or (GPS) following RNAV mean the same thing. My assumption that that was mainly used in the US was just that, an assumption, apparently wrong as they are in TXL as well.

I think your answer answers the OP's question the best! Clearly you are approved for RNP type operations! If you don't see those types of approval in the limitation section, then you are not authorized for RNP operations.

Interesting question though by the OP, forced me to do some studying as to nomenclature. 👍

Blogs,

GPS was replaced by GNSS simply because the term GPS was US centric, the NAVSTAR Global Positioning System (GPS), which originally was military based.

There was a different system put up by the Russians, GLONASS, but it used FDMA, and was not compatible with the US GPS CDMA signal, but has recently been switching over.

ICAO had to do something different by calling it the Global Navigation Satellite System.
The difference with GNSS, for example, with the EU Galileo system, is that this provides full integrity signal in a civilian system. It does operate on different frequencies than GPS, and receivers are designed to combine GPA and GNSS signals.