Are you using the FMS-3000 .../Q or /L

[Checks]

Dual FMS-3000's installed. A big debate at my company about what to file.

We are probably stupid but everyone gets wrapped up around the axle when it comes to the term "Required Navigation Performance for the route, ect, ect" . We have looked in our navigation capabiliites section but once again there are two answers to every question.

What are you all using?

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ADVANCED RNAV WITH TRANSPONDER AND MODE C (If an aircraft is unable to operate with a transponder and/or Mode C, it will revert to the appropriate code listed above under Area Navigation.)

/E ​

Flight Management System (FMS) with DME/DME and IRU position updating

/F ​

Flight Management System (FMS) with DME/DME position updating

/G ​

Global Navigation Satellite System (GNSS), including GPS or WAAS, with enroute and terminal capability.

/R ​

Required Navigational Performance. The aircraft meets the RNP type prescribed for the route segment(s), route(s) and/or area concerned.

​

Reduced Vertical Separation Minimum (RVSM). Prior to conducting RVSM operations within the U.S., the operator must obtain authorization from the FAA or from the responsible authority, as appropriate.

/J​

/E with RVSM

/K​

/F with RVSM

/L​

/G with RVSM

/Q ​

/R with RVSM

/W ​

 

[400A]

/Q unless you are RNP authorized (Pretty sure the unit is capable) then it would be /W

My only question is: Do you have dual GPS? (not sure if that is required) and are you sure it is dual FMS and not just dual RTU (Key pads) like most of the Premier's have.

 

[mike1mc]

After discussions with one inspector at FAA HQ, I was given the following advice a few years ago (NOT NECESSARILY FAA POLICY):

/G if using GPS (including FMS using GPS as primary navigation)
/L if above with RVSM (PROBABLY MOST AIRCRAFT)
/J if using FMS with DME/DME/IRU and RVSM-capable
/Q reserved for aircraft that meet RNP requirements in area of operation (ie. NAT/MNPS, WATRS+, RNP Approaches, etc.).

As the FAA moves forward with Performance Base Navigation, this designator will allow controllers to know who is authorized for reduced seperation and who is not. I have seen people use this designator when the aircraft has no RNP qualification approval or statement in the AFM.

Our company policy is to use /L or /J for all turbojets unless operating off-shore or flying international where RNP is required since we do not have RNAV (RNP) approach approval.

 

[mike1mc]

Another note:

Just because an FMS is RNP 0.3-capable, that doesn't mean the aircraft is certified. There needs to be a statement in the AFM Limitations Section (usually under FMS) that lists the applicable equipment and RNP approval.
GPS by design is equivilant to RNP 0.3, but that doesn't make a C172 RNP 0.3 approved.

Depending on the aircraft, a dual FMS-3000 installation should be certified for at least RNP-10 if not RNP-4/5. Also, don't confuse the RNAV1 and RNAV2 for SID/STARs with RNP. The same, but different. RNP requires an alerting function to be certified.

 

[BoilerUP]

Check your AFM supplement for the FMS-3000 and look under "Navigational Operational Capabilities"

In our CJ2+ (which has a single FMS-3000 unit and no second FMS/GPS-500) the FMS-3000 AFM supplement says dual installed units are capable of Oceanic/Remote LRN, NAT MNPS, RNP-10 and RNP-5/PRNAV but that capability does not constitute operational approval (ie you'd need LOA/OpSpecs to do so).

FWIW, I've been filing /L....and Cessna's demonstrator airplanes file /Q.

 

[hyper]

And if you're filing ICAO plans like with Fltplan.com for example, it's a moot point. Fill out the capabilities and the / will be your weight category. Ironically /L for mine.

 

[Checks]

Thanks for the replies. I made a mistake in the original posting: I meant to say /Q (GPS) or /W (RNP). Our AFM says RNP-10. Some guys think that means we can file /W.

 

[mike1mc]

Thanks for the replies. I made a mistake in the original posting: I meant to say /Q (GPS) or /W (RNP). Our AFM says RNP-10. Some guys think that means we can file /W.

You mean /Q (RNP). I think /W is just RVSM