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PBN Capability and flight plan equipment codes

In the US, many AFMS pre-dated the introduction of PBN. The FAA developed an AC 90-100A which referenced a spread sheet that was later turned into a pdf document and includes a list of GPS systems that are approval for RNAV 1 procedures. The non WAAS GPS GNS430/530 and G1000 systems are approved. Most other legacy GPS systems are not approved, including the KLN94



So GNS430/530 and G1000 will have RNAV SID/STAR included in the navdata database. If the GPS is not approved, you will not find these procedures included in the navdata database.

KUZA, United States

Emir wrote:

I guess that B2D2O2S1 is what you should put in flight plan.

I would not use O2 and although S1 is not wrong, I have yet to find a use for it. It does not block filing nor does it block an aircraft from flying an approach meeting the RNP APCH specification. In the US at least, O2 is only needed on a very small handful of procedures and I only know of one that requires it, the ZELAN4 SID at KATL and it is Turbojet only. O2 or RNP 1 is only required in the US when the RNAV SID or STAR requires the use of an RF leg. In the US, I would recommend using B2, C2, and D2.
B2 is for basic point to point RNAV navigation using GPS. C2 is for RNAV T and Q routes in the US using GPS which are RNAV 2 routes. D2 is for RNAV 1 SID, ODP, and STAR using GPS.

There is a bunch of stuff one can include in an ICAO flight plan that has no real application.

Last Edited by NCYankee at 03 May 17:55
KUZA, United States

NCYankee wrote:

In the US at least, O2 is only needed on a very small handful of procedures


RNAV 2 is primarily a US specification and it is not expected to be used in Europe. If the the aircraft is RNAV 1 certified then it is fully compliant RNAV 2.


RNP 1 applies in terminal areas. RNP 10: 1 expresses the lateral navigation accuracy in nautical miles which is expected to be achieved at least 95 per cent of the flight time by the aircraft operating within the airspace, route or procedure.


GNSS is the navigation system to support RNP APCH procedures. Characteristics of RNP APCH: – Straight segments, fly-by turns – Allows for two-dimensional (2-D) non-precision approach (NPA) and,– Allows for three-dimensional (3-D) approaches with vertical guidance.
Last Edited by Emir at 03 May 18:12
LDZA LDVA, Croatia


From your reference, D2 indicates:

Like all navigation specifications, the RNAV 1 specificationincludes all flight crew and airborne navigation system requirements. Operators wishing to indicate P-RNAV (Precision RNAV) within Europe should select an RNAV 1 alphanumeric.

Is there any procedure in the Europe that uses or requires O2 verses D2? Please provide a reference for the procedure if there is one.

Will you be denied a request to fly an RNP approach if you fail to specify S1 or S2?

KUZA, United States

AFAIK ATC is not aware of what your flight plan equipment list contains.

Eurocontrol refuses to validate flight plans which fail to contain Mode S and 8.33 and, if appropriate, RVSM. This is one previous thread.

What I am fairly sure ATC do is they assume that GA will generally not have certain capabilities. I have never been asked to fly something which the KLN94 could not do For example RNAV transitions.

Shoreham EGKA, United Kingdom

Not PBN related but certain airports might file an MOR if you fly an NDB approach without an ADF, i.e. using an IFR GPS overlay.

Oxford (EGTK), United Kingdom

On the da42 non waas I have flown during my Meir, string was PBN/B2C2D2S1 and integrity was monitored by the g1000 as well as 530. When integrity is lost (4 sat or less) during an lnav approach, you have a raim alert and lnav becomes orange instead of magenta. I had it in the SIM but didn’t encounter in cruise although we had a planned loss if integrity (seen on augur before the flight), because we just didn’t start a lnav approach.

LFMD, France

certain airports might file an MOR if you fly an NDB approach without an ADF, i.e. using an IFR GPS overlay.

How will they know?

How about the majority of SR22s not having an ADF/DME?

Shoreham EGKA, United Kingdom

The flight plan would not list ADF as equipment.

I doubt many Cirrus use NDB approaches in anger.

Oxford (EGTK), United Kingdom


Thank you all.

Basically EASA GM2NCO.IDE.A.195 Navigation equipment

(Link: , pg. 58)


If the POH (or POH supplement – AFMS) contains a reference that the GNSS receiver is appropriate according FAA AC 20-138 it can be used for en-route, terminal and approach, namely down to BRNAV/RNP5 and PRNAV/RNP1.

So even for non WAAS, non SBAS & non EGNOS installations I understand this means PRNAV/RNP1 SIDs and STARs and RNP approaches down to LNAV (and not LNAV/VNAV !) minima.

This Garmin 430 document says the

GPS is certified to TSO C129, Class A1, en route, terminal and approach.

FAA AC No: 20-138D says regarding TSO C129:

c. TSO-C129a was cancelled effective October 21, 2011, but there is no plan to withdraw TSO-C129 authorizations. TSO-C129a cancellation will not affect existing authorizations. Manufacturers can continue production according to their existing TSO-C129 TSOA/LODA. Additionally, the equipment is still eligible for installation according to existing airworthiness approvals and is eligible to receive new airworthiness approvals.

Thankfully, the FAA provides a nice FAQ in their document. I’m not 100% clear if (cancelled) TSO-C129 Class A1 certified GNSS receivers such as the GNS430 (non W) fulfill the criteria for TSO-C129 but here it goes:

(1) Question: Are technical standard order (TSO)-C129 Class A1 GPS and TSO-C146 Class Gamma GPS/SBAS equipment RNAV or RNP systems?
(2) Answer: Both. RNAV systems conform to the ICAO performance-based navigation specification for total system error (TSE). RNAV total system error is the 95% probability that the navigation system accuracy remains within the limits defined for the RNAV operation. For example, during an RNAV-1 operation the TSE remains within one nautical mile of the desired path 95% of the time (see Figure 1 below). RNP systems conform to a performance-based navigation specification based on RNAV capability that also includes requirements for on-board performance monitoring and alerting. For example, during an RNP 1.0 operation, the TSE remains within one nautical mile of the desired path 95% of the time, and on-board performance monitoring provides the pilot with an alert when the probability that TSE exceeds 2×RNP is greater than 10-5 (see Figure 2 below). RNP is an RNAV subset that also includes a requirement to provide on-board navigation system accuracy performance monitoring and alerting which means an RNP system is also an RNAV system. GNSS equipment provides accuracy performance monitoring and alerting which, by definition, makes it both an RNAV and RNP capable system.
AC 20-138D
Note: TSO-C129 Class B/C, TSO-C145, and TSO-C196 sensors provide both RNAV and RNP capability when interfaced to an appropriate navigation computer (such as TSO-C115c).
(a) By definition, TSO-C129 Class A1 and all TSO-C146 Class Gamma GNSS equipment provides an RNAV capability that includes on-board performance monitoring and alerting. This equipment has the capability to perform RNAV(GPS) approaches to at least the LNAV line of minima.
(b) RNAV(GPS) approaches require GPS, which includes on-board performance monitoring and alerting. Therefore, an RNAV(GPS) approach is an RNP procedure where the initial, intermediate, and missed approach segments are RNP 1.0. The LNAV final approach segment is RNP 0.3.
(c) None of the preceding statements should be confused with RNP AR that requires special aircraft and aircrew approval. Neither TSO-C129 Class A1 GPS nor TSO-C146 Class Gamma GPS/SBAS can qualify for RNP AR operations without additional aircraft and aircrew approvals (see appendix 2).

No RNP AR procedures can be included in the navigation databases of equipment that is not approved for RNP AR operations. RNP AR approach procedures are titled RNAV(RNP) and have an “authorization required” designation printed on the charts.

Next step is checking, e.g., a Cirrus SR22 G2 POH for an applicable supplement.
Here it is for the GNS430 installation:

The GNS 430 is capable of providing IFR enroute, terminal, and approach navigation with position accuracies better than 15 meters. The system utilizes the Global Positioning System (GPS) satellite network to derive the airplane’s position (latitude, longitude, and altitude) and the altitude digitizer to enhance the altitude calculation.

Quoting further

Provided the GPS Navigator is receiving adequate usable signals, it has been demonstrated capable of and has been shown to meet the accuracy specifications of:
1. VFR/IFR, enroute, terminal, and instrument approach (GPS, VOR) operations, that is, enroute, terminal, and instrument approach within the U.S. National Airspace System, North Atlantic Minimum Navigation Performance Specification (MNPS) Airspace using the WGS-84 (or NAD 83) coordinate reference datum in accordance with the criteria of AC 20-138, AC 91-49, and AC 120-33. Navigation data is based upon use of only the global positioning system (GPS) operated by the United States.
5. GPS instrument approaches must be accomplished in accordance with approved instrument approach procedures that are retrieved from the Navigator’s NavData database. The database must incorporate the current update cycle.
a. Instrument approaches must be conducted in the approach mode and RAIM must be available at the Final Approach Fix.
b. Accomplishment of ILS, LOC, LOC-BC, LDA, SDF, and MLS approaches are not authorized in GPS mode.

Until now it looks good. Somehow we can conclude, going from the EASA GM1 via FAA AC20-138 to the POH Supplement that RNP1 SIDs, STARs and APPs can be flown using a “legacy” GNS430 (non W).

And now… quoting again the GNS430 supplement of an older Cirrus:

7. The Garmin GNS 430 meets RNP5 (BRNAV) requirements of
AC 90-96 and is in accordance with AC 20-138, and JAA AMJ 20X2 Leaflet 2 Revision 1, provided it is receiving usable navigation information from the GPS receiver.

If point 7 means overall only RNP5 and BRNAV then this supplement, especially it’s referring to “GPS instrument approaches” is useless, as to my knowledge there are no GPS approaches (RNP APP) based on RNP5. AC-90 06 has been cancelled, so I dig further.

Thanks @NZYankee for referring AC-90-100A which says:

c. The following systems meet many of the requirements defined in this AC. Such equipment still requires evaluation by the manufacturer against all the functional and performance requirements in this AC. The RAIM prediction program should comply with the criteria in AC 20-138A, paragraph 12.
(3) Aircraft with TSO-C129/C129a Class A1 (without deviating from the functionality described in Appendix 3 of this document) installed for IFR use IAW AC 20-138 or AC 20-138A.

So, somehow the circle closes and I conclude that GNS430 (non W) can fly PRNAV/RNP1 SIDs, STARs and APPs (LNAV minima).

Attached: Handy doc showing icao fpl codes.

always learning
LO__, Austria
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