Transitioning to BRNAV from the terminal airspace

[JonDyer]

Hi

As we know, all European en-route airspace above FL095 is B-RNAV and any aircraft flying within it must be equipped and certified.

For non P-RNAV certified aircraft "RNAV" SIDs and STARs must not be used and SIDs & STARs that are used must utilise conventional aids (Raw Data)

Can anyone point me to the source documentation that describes at which point in the departure process we change from Raw Data to B-RNAV?

Is it for example,
Above MSA?
After the final SID waypoint?
Above FL095?
Something else entirely?

I am not being lazy - I have checked out ECAC Nav, TGL10 and ICAO 9650 and I didn't find the specific answer there nor any reference to the authoritative source.

Where else should I be looking?

Thanks.

[Microburst2002]

The BRNAV airspace is above a given level, 95? and in BRNAV terminal procedures. You should be cleared to a non RNAV STAR, or radar vectors or own navigation. All you have to do is not to accept any RNAV STAR.

[FE Hoppy]

Once you are no longer flying the SID (last waypoint) and above FL095.

You can't be "en-route" if you are still flying a procedure and the airspace below FL095 isn't BRNAV.

[JonDyer]

Once you are no longer flying the SID (last waypoint) and above FL095.

You can't be "en-route" if you are still flying a procedure and the airspace below FL095 isn't BRNAV.

Thanks. I am not disputing what you say but this SID (http://www.ead.eurocontrol.int/pamslight/pdf/4e415453/EG/C/EN/Charts/AD/EG_AD_2_EGWU_6-3_en) (Northolt Buzad 3X) finishes at Buzad at 5000ft. Assuming I have not had further climb by Buzad, is it anticipated that I will be using ground-based nav aids to navigate to the waypoints below FL095?

Because B-RNAV is mandatory above FL095, is it prohibited below?

Once I am above MSA is there anything preventing me from using FMS direct-to and flying LNAV?

It is because of these questions that I am looking for source documentation.

[Microburst2002]

If you have rnav in the flight plan the ATC can give you direct to RNAV waypoints at any time, even below MSA. You still are responsible for terrain separation, though. RNAV is not prohibited anywhere.

You cannot fly a procedure for which you don't have a cerfification. If you are not PRNAV certified but you are BRNAV certified and the airport doesn't have BRNAV departures anymore, then you need a conventional SID or an alternative clearance, such as "turn left direct to BUZAD" or radar vectors.

You can fly RNAV all the way from one airport to another without being PRNAV certified, as long as you are never cleared for a PRNAV procedure that you are not certified for.

In your BUZAD 3x, after BUZAD you can follow any enroute clearance they give you. There is no need to lay this fact down in a regulation. The regulation specifies what you cannot do rather than what you can.

[IO540]

I can't help you with the documentation/references but you may be slightly confusing BRNAV and PRNAV (see your first post).

BRNAV is the capability to navigate to virtual waypoints (not navaids, or navaid referenced; e.g. ORTAC is just a waypoint in space, defined by lat/long) to RNP5 accuracy i.e. be within 5nm of track 95% of the time. This requirement is met by INS (in big jets) or with an IFR GPS (in everything smaller). You also need to have an approved installation which means a TSO GPS and a CDI mounted within a specific primary pilot viewing angle.

AIUI, a BRNAV installation allows you to fly in BRNAV airspace (FL095+ generally; this level has recently been reduced in the UK to all CAS) and allows you to fly "RNAV" SIDs/STARs if the entire procedure can be loaded in one piece from the GPS database.

Getting a BRNAV approved GPS installation is easy. I think the paperwork is a few hundred quid under EASA.

PRNAV is a different thing. It is basically equivalent to RNP1 but there are additional certification requirements for both the aircraft and the crew. The paperwork is also today an EASA Major Mod and costs 4 figures.

In practice, an IFR GPS meets the RNP accuracy requirements with a huge margin, but avionics reality has never got in the way of aviation regulation which is firstly a job creation scheme :)

You also do not, in practice, fly SID/STAR procedures using raw data. You use a GPS. Most people also use a GPS for NDB/VOR nonprecision approaches. Only an ILS is flown using the ILS receiver.

For private flight, there are no regs which stipulate what equipment is used in each stage of flight.

For commercial flight, the AOC will include a manual which specifies what you do and how, etc. In general, one is allowed to fly NP procedures with a GPS (or INS) but the underlying navaids need to be functioning (not notamed INOP) and tuned in.

There is a real issue with an increasing number of airports whose published SIDs/STARs are all PRNAV. However most (all?) of them give you the option to declare this to ATC and then you get vectors or some other procedure. Most aircraft in the world are not PRNAV and probably never will be. But RNAV capability is simply assumed by ATC everywhere.

[JonDyer]

If you have rnav in the flight plan the ATC can give you direct to RNAV waypoints at any time, even below MSA. You still are responsible for terrain separation, though. RNAV is not prohibited anywhere.


Thanks - that is what I was getting at.

You also do not, in practice, fly SID/STAR procedures using raw data. You use a GPS. Most people also use a GPS for NDB/VOR nonprecision approaches. Only an ILS is flown using the ILS receiver...

... For commercial flight, the AOC will include a manual which specifies what you do and how, etc. In general, one is allowed to fly NP procedures with a GPS (or INS) but the underlying navaids need to be functioning (not notamed INOP) and tuned in.

I agree and that is my point - where an OPS manual specifically prohibits using a GPS overlay, or LNAV to fly SIDs and STARs (due to lack of P-RNAV certification) then at which point in the departure may the pilots use a Direct-To?

Microburst2002 has pretty much answered that.

I know this seems pretty pedantic and obscure but airports with exclusively P-RNAV departures are becoming more and more common (as IO540 has noted in other threads) and I am interested in whether the rules are routinely being ignored or are instead just misunderstood.

It's hard to say "thanks for your input" without it sounding sarcastic - but I assure you I mean it!

[IO540]

I know this seems pretty pedantic and obscure but airports with exclusively P-RNAV departures are becoming more and more common (as IO540 has noted in other threads) and I am interested in whether the rules are routinely being ignored or are instead just misunderstood.IME, the whole thing is just ignored.

ATC couldn't care less how you navigate providing you are in the right place. The PRNAV stuff is seemingly only at airports big enough to have radar (or a radar feed).

And if it was taken seriously, the great majority of traffic could not use that airport.

This begs the question of who actually decides "hey we need to make this place PRNAV" and why. Some manager who has just come back from a Eurocontrol seminar, perhaps? I've been to some of those and the officials (well, usually one very arrogant individual) make a very forceful case, which sounds good if you are not a pilot yourself, and most airport managers are not pilots.

IMHO, what would be a real problem would be if enroute airspace became PRNAV-only. Then, Eurocontrol could enforce it at the IFPS flight plan validation stage - like they already enforce 8.33 (if filing above FL195) and RVSM. There is a database, I believe, of PRNAV approved aircraft, and this can be made accessible to IFPS, or even to ATCOs. I have been told by UK ATC that there is a proposal in the pipeline for making the LTMA PRNAV-only, but this stuff has been brewing for an awfully long time.

[bookworm]

I agree and that is my point - where an OPS manual specifically prohibits using a GPS overlay, or LNAV to fly SIDs and STARs (due to lack of P-RNAV certification) then at which point in the departure may the pilots use a Direct-To?

If it's the Ops Manual that prohibits using BRNAV for SIDs and STARs, wouldn't you expect the Ops Manual to specify when the prohibition is lifted?

[JonDyer]

If it's the Ops Manual that prohibits using BRNAV for SIDs and STARs, wouldn't you expect the Ops Manual to specify when the prohibition is lifted?

I would, and the one I am thinking of does not.

I do think that Microburst2002 is probably right about everything being permitted which is not specifically prohibited.

I know if there was something out there to be found then you would have produced it, therefore it's not there, QED!