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Slow thinking in the morning, AFMS?

ESSB, Stockholm Bromma

OK, but they could have just redefined BRNAV as RNP 1.0 and be done with it, instead of creating this massive job creation scheme.

In the USA, the FAA has grandfathered all IFR-certified private aircraft into PRNAV - valid for US airspace only. Do they know something??

AFMS = approved flight manual supplement.

For example if you have any major piece of avionics then you need a supplement in the flight manual (the POH) for it. That supplement defines stuff like operating limitations. Many avionics have been installed without this, and are probably worthless for regulatory compliance. In some cases, getting the AFMS is trivial but in others it can be difficult or even uneconomical. This is one I did recently.

Shoreham EGKA, United Kingdom

Ah yes, didn't connect with the S at the end... Our AFM has the TGL 10 in it as standard.

ESSB, Stockholm Bromma

I think P-RNAV airspace will end up being FL200 or 195 up and around busy terminal areas at lower alt. I doubt it will shut down GA IFR.

And I continue to disagree about LPV. It is the future and is coming whether you like it or or are equipped or not.

These are the same debates that happened around 8.33. It will be rolled out and people will eventually have to upgrade or will have operating limitations.

EGTK Oxford

I don't recall saying LPV is not the future.

"LPV everywhere" would be a great thing to have. I would re-fit now if that was the case. Of course it won't happen in most of Europe, due to the regs mandating ATC for the approach, but there is another thread on that...

My comment was on the present operational relevance, but PRNAV rather than LPV. But even on LPV, in the UK, there is exactly 1 LPV approach that's published. There are almost no Customs airports in Europe that have LPV and no ILS.

The decision an aircraft owner has to make is when (or whether) to spend the money to acquire a specific capability, relative to his mission profile.

What should not be happening, but looks like happening with PRNAV, is that flying the existing mission profile is going to cost (many or most people) a lot more money.

IFR has never been rocket science and there is no obvious reason why it should become rocket science.

There is also no apparent need for the accuracy to be improved over what is currently being routinely achieved in IFR ops and has been for well over a decade.

Imagine the FAA trying to screw the US pilot community with something like this...

Shoreham EGKA, United Kingdom

In some ways with ADS-B they are doing the same thing in the US but least they make it worth people's while by adding free weather and traffic.

EGTK Oxford

Here in the US, PRNAV is RNAV 1. It only shows up in departure (SID) and arrival procedures (STAR). To distinguish the procedure from one based on ground based navigation aids, it has (RNAV) in the title. To be assigned one by ATC, one must use the ICAO flightplan form and the equipment capability must be specified IAW US only equipment codes (Field 10 must have a Z and field 18 must have NAV/RNVE2A1D1). The requirements for compatible equipment and training are covered in AC 90-100A:

Since the AC was published long after most GPS AFMS were written, a supplementary Excel spreadsheet was developed and maintained by the FAA that lists the approved GPS units that may fly the RNAV SID and STAR:

The spreadsheet also indicates if a particular GPS may be used in the US NAS for substitute navigation for DME, ADF, and VOR. Pretty much all of the GPS units prior to the GNS430 are not approved! The GPS units which are approved include the GNS430/530; GNS480; GNS430W/530W; the G1000 systems, and the GTN series. The GTN series is not included in the spreadsheet because its AFMS covers the subject.

Peter, the KLN94 is not approved! It is also not approved for VOR substitution in the US NAS. The reason it is not approved is that it does not support the CF Leg terminator in the database. This prevents RNAV SID/STAR procedures from being coded in the database although SID/STAR based on ground nav aids are included in the database. Not having the CF Leg terminator in the database is what prevents the unit from being approved for VOR substitution as well, even though the same effect can be obtained by using OBS mode.

KUZA, United States

As of now, there are very few airports where PRNAV is already mandatory and I do not think that this will change in the near future. Among them are Amsterdam and (soon) Munich. Therefore I don't really think that PRNAV will be of much concern to many private pilots in the next couple of years.

Does that mean it will effectively also be mandatory at Augsburg?

EGTK Oxford

P-RNAV is already mandatory in the Prague area although ATC don't really care.

Even though I can be 5NM off enroute today, I can imagine what kind of conversation I would have with ATC if I insisted on being correctly established on the assigned airway

Watching my x-track error to Berlin yesterday, it was generally 0.01nm, only going to 0.03nm in a wind shear or turbulence. Peter's point is right, it didn't become suddenly more accurate since I received an FAA P-RNAV LOA that day!

EGTK Oxford
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