GNSS on conventional procedures
 

Hello,

I have a question concerning the use of GNSS (GNS430, G1000, etc.) on procedures other than BRNAV/GNSS. In other words, conventional procedures.

I know this topic is subject to approval of the installed equipment. However my questions are:

1) If i'm correct a GNSS can be certified to allow you to fly a:

SID
STAR
Initial approach
Final approach NPA
GNSS/GPS & RNAV/PRNAV procedures

But does this has to be mentioned or are some included in the "approved for IFR" (like for example flying an SID, cant find an example of a POH stating that the use of GNSS is allowed for an SID)

(keep in mind, conventional procedures, Europe reg., and of course with navaids tuned for backup)


--and--

2) Since BRNAV is required above FL095 in Europe at what point do you switch over from conventional navigation to the GNSS equipment and back when your equipment is not approved for certain phases of the flight?


I've been trying to find some documentation concerning the limitations of the installed GPS/GNSS. But since these limitations are airplane specific these are hard to come by. So please feel free to quote your POH :)


Thanks in advance! :ok:

Does this help answer your question?

http://https://static.garmincdn.com/...an_Information

Look at ICAO FPL's and eligibility on the left tab.

You may have a supplement in the AFM/POH with what you can/cannot do with the specific fit.

Thanks for the reply 500,

Very interesting! However this information only covers RNAV/RNP/GPS approaches.

I am aware of the supplement, my POH says that my equipment is only B-RNAV approved (thus to my understanding only the en-route phase) hence question #2, at what point can i start using my GPS and where do i have to revert to conventional navigation? I've heard many different opinions on this one. At start of STAR, when descending below msa, ...

Does a POH literally says: "GPS can be used for conventional SID, STAR, approach until FAF/FAP, ..." when the equipment is approved to do so?

As I said, I'm unable to find this information on other aircraft.

Many videos online of pilots doing full flights on GPS and only tuning the ILS freq for landing. One comes to mind of a guy doing an SID that states turn at 500ft and he ends up turning at 2500ft because he was following his GPS.. :\

A G1000 or GNS430 (is yours a 430 or a 430W?) can be RNP1 approved generally, so from the DP/SID, En-route, Arrival, Initial, Intermediate and Missed approach. Crew approvals for certain RNP is another issue.

See page 6 http://www.eurocontrol.int/sites/def...-pbn-a-rnp.pdf

The POH or supplement is more likely to say RNP capabilities, not "can/can't be used for..."

If yours states B-RNAV only then it is B-RNAV only. I'd have thought you can use it from the word go, but backing up by identing and displaying conventional navaids.

Please don't take my advice - ensure what approval you have with your particular fit. Which type of aircraft and what specific kit is installed and approved?

More reading: http://www.uasc.com/documents/whitep...WhitePaper.pdf

It might say BRNAV and RNP5, not sure I'll check it when i'm home. Definitely not RNP 1. Equipment i'm using is a GNS430W.

As far as i'm aware in the US, the equipment gets certified and that certification is valid to all aircraft the equipment is installed in.

In Europe however every aircraft+equipment needs to be certified. More certification in example RNP1 = more €€€, so not every GNS430W/G1000 has the same certification. (please correct me if i'm wrong)


So basically, when for example a POH says RNP 1 capability it can be used as primary navigation for conventional procedures (with backup of course) for all phases of flight u said without further mentioning in the POH.

Can it ever allow you to fly (lateral aspect) of a VOR or ADF approach?

http://support.diamond-air.at/filead...15e-A33-r1.pdf

If your setup was approved, you would have a supplement similar to the one above for a DA40 series airframe.

I believe that even for a part 91 operator in the USA you would need an LOA for certain RNP operations.

And the crew may require training. We had to in order to obtain P-RNAV approval.

It can if the equipment is approved.

Do you happen to have a link to the g1000 supplement stating when GPS can be used on non RNAV/GPS procedures? This one covers PRNAV and SBAS operation :)

The part of B-RNAV, P-RNAV, GPS procedures is clear to me, u need approval and even training for P-RNAV to use it. if its not mentioned in the book, you can't do it. Simple.

What is not clear is:

When are you allowed to fly a procedure created for VOR/ADF/DME navigation, couple the CDI to the GPS and use the GPS for navigation instead of having to use 10 different frequencies to fly a full procedure.

To my understanding this has nothing to do with RNAV which is a completely different category of procedures. A VOR approach has nothing to do with RNAV, and P-RNAV approach has nothing to do with a VOR.

P-RNAV allows you to fly arrival, initial, intermediate, missed and departure. But only if that procedure is a P-RNAV procedure :confused: or am i realy missing something here? :(

The arrival and departure parts are correct but not the missed as far as I'm aware.

I don't fly G1000 aircraft (luckily!) so cannot give you the manual or supplement.

http://easa.europa.eu/system/files/d...MC%2020-4A.pdf

Maybe someone who flies conventional procedures on daily base whilst relying on his/her G1000 can clear this one out :)

Or someone with the supplement that can point out the part where it makes clear when you can/can't replace conventional navaids with GPS guidance.

From airbus FCOM:

FMGS lateral and vertical navigation has been certified for after takeoff, en route, and terminal area operations, for instrument approach procedures (except ILS, LOC, LOC-BC, LDA, SDF and MLS), and for missed approach procedures.

Now this is a clear statement of what you can and can not do!

BTW thanks for the help 500, appreciate it!

http://static.garmincdn.com/pumac/19...-07_0A_Web.pdf

Here is a generic G1000 manual for Cessna's.

It is possible that what I mean is the overlay however i thought these where only allowed to be used when published.

An overlay should say, for example, VOR/GPS RWY 27 etc. in my present jet's FMS's it would be shown as VOR27G (with the added benefit of a VPATH), don't know about the G1000 system - it's been a long time since I flew a DA42, my only Garmin type. Even so, if available, I don't see why you wouldn't use all the 'tools of the trade' and load that approach on the G1000 and back it up with the raw data needles. Why dive & drive?

I don't even think that the FAA regs still require the navaid to be tuned anymore... That's just down to airmanship I guess. EASA still does require this AFAIK.

I believe you could use LNAV for conventional approaches as long as raw data is monitored.

Indeed EASA still requires you to tune the Navaid, can't find the offical reference right now.

If the approach would be labeled as VOR RWY 27 (no GPS) can i still use the overlay?

What i mean by "using the GPS" I'm talking about the procedure that can be loaded by entering the procedure (proc) menu in the garmin.

This provides you with lateral guidance of the procedure. (the LNAV you mention) but is this an approved way of navigation in this phase? :p

EASA is rather unclear about this subject as is my POH :s When compared to the A32F FCOM which very clearly states this.. :s

Its funny how such an 'easy' subject can be this unclear/bad defined :)

from here http://dcaa.trafikstyrelsen.dk:8000/...05th%20ed..pdf

PANS-OPS, you'll have to check for the latest version as I don't have time.

Yes! that's what I've been looking for! :D:D:D

I assume "basic display" is the HSI

Is RMI sufficient for this? Within 10° for ADF; 5° for VOR

Just remember that all fixes in a conventional procedure are designed, effectively, as flyover waypoints. If you fly them as fly-by waypoints you may well end up outside the obstacle protection area used to design the procedure...

So I got myself confused again.

Doc 8168 says FMC/RNAV equipment can be used for conventional procedures provided that.....


Now my question is, what is the use of RNAV overlays then?

If I can simply use my RNAV equipment on every conventional procedure what makes overlays so different? They have the same requirements but are only allowed when published :ugh:

From supplement Garmin GNS 430W:

Is this:
-EASA: You can do it
-Garmin supplement: nope sorry, you cant unless an overlay is published

???

It's a technicality and CYA statement on the part of Garmin, I suspect.

If an RNAV overlay is published, you can use GNSS equipment EXCLUSIVELY to fly the procedure.

If there is no overlay, the appropriate NavAids (VOR, DME, etc) MUST be tuned and their "raw data" displayed on the appropriate, certified instruments (per EASA, FAA, and all other A's I know of). Once that requirement is satisfied, NOTHING prevents you for actually using the GNSS equipment as your real-time reference while flying the procedure. Just remember that the tuned NavAids are primary and required, and that you cannot continue the procedure using the GNSS equipment if a primary NavAid should fail.

So I can not fly the outbound of a procedure turn (based on a VOR) using my GPS information displayed on the HSI and the VOR on my RMI?

Correct?

Same for departures?

If your RMI is certified as an IFR instrument, you can use that for your VOR course display.