RNAV REQUIRED on approach plate - meaning?

[photofly]

The ILS RWY 08 at CYTZ is placarded "RNAV REQUIRED".

The approach has IAF called SEKUX, and IF called BORID, which is on the localizer, at 7.5 DME.

I know I don't have the whole approach loadable in my IFR-certified GPS receiver, because it doesn't include ILS approaches.

Assuming (it's a long-shot) that SEKUX and BORID are in the GPS database, can I legally program them as waypoints in my flightplan and shoot the ILS that way?

That would make it "the same" as using the GPS in lieu of an ADF, perhaps.

I won't get the RAIM0.3 but since I'm not using the GPS past the intermediate fix where I'd still be at RAIM1.0 anyway there's no difference there.

Alternatively, is there somewhere that specifies "RNAV REQUIRED" means an FMS must be used? In which case I'm toast.

[modi13]

It's the same as an ILS/DME approach, except that RNAV is used to identify waypoints instead of DME.

[scopiton]

I know I don't have the whole approach loadable in my IFR-certified GPS receiver, because it doesn't include ILS approaches.

Assuming (it's a long-shot) that SEKUX and BORID are in the GPS database, can I legally program them as waypoints in my flightplan and shoot the ILS that way?

from what I know, you can't conduct an IFR approach with an IFR certified GPS who doesn't have the IFR approach you're intending to fly loaded in the database. this is in regards to legallity, even if you have raim prediction and found that the 2 waypoints have the correct coordinates matching those on the plate.
is your HSI linked to the GPS ?

[photofly]

from what I know, you can't conduct an IFR approach with an IFR certified GPS who doesn't have the IFR approach you're intending to fly loaded in the database.

You can, for example, if you're flying an ILS and using the GPS only to identify the NDB at the FAF. I don't think the GPS has even to be approach certified in that situation, although this one is.

I'm not sure in my head if this is similar, or different.

Yes, the GPS drives the HSI. (I think that's a condition for IFR certification of an installation).

[ahramin]

An IFR GPS means you are RNAV equipped. You can use it to identify fixes on an approach as long as they are named fixes and retrieved from the database. You cannot use an IFR GPS to identify DME fixes with no name.

[scopiton]

AIM - COM 3.16.5.2

All approaches must be retrieved from the avionics database, and that database must be current. While it is sometimes acceptable to use pilot-generated waypoints en route, it is not permitted for approach procedures, as any database or waypoint coordinate errors could have serious consequences.

you can only use the GPS when in lieu of a conventional nav aid provided it's not working on the ground. COM 3.16.9
when you have no conventional nav aid but only an RNAV approach, you can't do it if approaches are not loaded in the GPS, as stated above.

[The Hammer]

You will never get 0.3 sensitivity on an ILS approach because the GPS/FMS will not switch to approach mode (activate) on precision approaches (localizer/ILS). It is there for advisory only and where I work the main reason we enter it is for Missed approach guidance only.

[ahramin]

AIM - COM 3.16.5.2

All approaches must be retrieved from the avionics database, and that database must be current. While it is sometimes acceptable to use pilot-generated waypoints en route, it is not permitted for approach procedures, as any database or waypoint coordinate errors could have serious consequences.

you can only use the GPS when in lieu of a conventional nav aid provided it's not working on the ground. COM 3.16.9
when you have no conventional nav aid but only an RNAV approach, you can't do it if approaches are not loaded in the GPS, as stated above.

Scopiton, COM 3.16.5.2 applies to GNSS Based RNAV Approach Procedures. An ILS is not an RNAV approach. In addition, whether or not a conventional navaid is working has no bearing on using an RNAV system in lieu.

Photofly, the section you are looking for is COM 3.16.9. You are correct that the GPS does not have to be approach certified but the database does have to be current and it does have to be an approved GPS and installation.

[ahramin]

By the way, for those who are interested, an RNAV system does not have to be an FMS, and does not even have to have GPS. An old KNS 80 or something similar still qualifies for RNAV. Strictly RHO/THETA.

[CID]

This isn't a GNSS approach procedure. It's just an ILS/DME that has also has some RNAV fixes. I haven't found clear direction for this procedure but between the AIM and AIC 16/08 you can glean that you need an GNSS navigation system approved for at least "terminal" operations and a database that has those RNAV waypoints. And of course an ILS system and optionally a DME. Although there is provision in the rules to use GNSS in lieu of the DME.

Note that the RNAV waypoints and DME fixes are just there to intercept the ILS. You don't use the GNSS past the FAF.

[CID]

ahramin, I disagree. Although it is truly an RNAV system, the KNS 80 doesn't meet the current performance requirements and certainly doesn't have a controlled database to pull the waypoints from. Beleive it or not, not even an old Garmin 100 would meet the requirments.

Funny...the missed approach is to the St. Catherines NDB. But you can use the GNSS for that too!

[ahramin]

CID, I didn't mean for this particular approach (which btw I see is ILS/DME RWY 08, not ILS RWY 08 as stated).

I was referring to RNAV in general. Just to clarify (since you're here anyway ), I can still fly point to point IFR enroute with a KNS 80 right?

[photofly]

which btw I see is ILS/DME RWY 08, not ILS RWY 08 as stated

Point taken. I do have DME though.

Looks like it might be a feasible approach then. Next step is to ask Toronto Centre if they'd clear me from SEKUX rather than LINNG, MUSET, ELUKI etc.

[ahramin]

Looks like it might be a feasible approach then. Next step is to ask Toronto Centre if they'd clear me from SEKUX rather than LINNG, MUSET, ELUKI etc.

I'd have them all plugged in and ready to go just in case.

[costermonger]

you can only use the GPS when in lieu of a conventional nav aid provided it's not working on the ground. COM 3.16.9

Subject to any overriding conditions or limitations in the aircraft flight manual (AFM) or AFM Supplement, GNSS may be used to identify all fixes defined by DME, VOR, VOR/DME and NDB, including fixes that are part of any instrument approach procedure, to navigate to and from these fixes along specific tracks, including arcs, and to report distances along airways or tracks for separation purposes. This can be done as long as there is no integrity alert, and provided that all fixes that are part of a terminal instrument procedure (arrival, departure, or approach) are named, charted and retrieved from a current navigation database. GNSS may be used to identify fixes defined by ground-based aids, even if they are temporarily out of service.

3.16.9 says you can use GNSS to identify fixes even if the traditional source is unavailable, not that the traditional source *must* be unavailable.

[photofly]

I'd have them all plugged in and ready to go just in case.

That's the issue. It's an old GPS, and it's would be a pain to have to program them all in, during the period after being cleared for the approach:

Centre: "...Mike Zulu, confirm destination City Centre? You appear to be heading for Hamilton"
Me: "Sorry, it's taking a while to get the waypoints programmed in."

[bic]

costermonger, i believe this is for a GPS overlay approach and the approach plate must specify GNSS on it ( ILS (GNSS) 24, NDB (GNSS) 25 ). If it is not , you can not use it.

[ahramin]

bic, AIM COM 3.16.9 has nothing to do with overlay approaches. 3.16.5.2.2 deals with that.

[bic]

Alright, but Costermonger comment looks pretty much like the definition of an Overlay approach, that is why i good confused.

[scopiton]

Scopiton, COM 3.16.5.2 applies to GNSS Based RNAV Approach Procedures. An ILS is not an RNAV approach. In addition, whether or not a conventional navaid is working has no bearing on using an RNAV system in lieu.

I roger that, but the plate states "RNAV required", that's why I came up with 3.16.5.2
the ref you're giving is acceptable but it refers to use of GPS in lieu of grd base, or the title of the plate would mean that to use those waypoint with a GPS to conduct the approach you need it to be RNAV approved and able even though it's not labeled RNAV. at least that's how I understand the plate's mention.
it would worth giving a call to those ATC guys reading the forum to have a clear answer
of course with an updated GPS any approach is flyable if you want, provided you don't get caught, which is another subject

[tca]

I'd have them all plugged in and ready to go just in case.

That's the issue. It's an old GPS, and it's would be a pain to have to program them all in, during the period after being cleared for the approach:

Centre: "...Mike Zulu, confirm destination City Centre? You appear to be heading for Hamilton"
Me: "Sorry, it's taking a while to get the waypoints programmed in."

Does your gps have the option if saving routes? If so just programme the full sequence, then load the saved route and the appropriate daylight when cleared. Have done this with old Trimble 2000 and with garmin 250.

Good luck.

[xsbank]

You may be 'able' to build the approach with your gps but you are not "allowed" to. You may be able to "get away with it" too until something goes wrong. Why not just fly the ILS?

[Panama Jack]

There is one airport I fly to where the ILS requires RNAV with RNP 1. Why? Look beyond the Decision Height if you ever had to do a missed approach and that is where you find the answer. (Not applicable to the "we ain't missin'" crowd).

[BTD]

I am fairly certain the RNAV REQUIRED on these approach plates as with what Pearson used to say (probably still does) is to prevent full procedure approaches. It would suck for ATC to clear an approach and have another person in trail behind them, only to have the first guy initiate a race track at the FAF. I don't have a CAP in front of me now, but it probably doesn't show a procedure turn on the plate. Is the RNAV REQUIRED written in the middle of the plan view of the approach plate? I don't think its up next to the title of the plate.

RNAV is not required for the actual approach. You will never see a plate that says ILS 08 (GNSS 08). There is no such thing as an overlay ILS approach. All they want to be able to do is clear you direct to a point to initiate an approach.



BTD

[CID]

I don't understand the confusion here. The chart isn't suggesting you build the procedure and fly the ILS using GNSS. It's almost painfully obvious that the RNAV portion is just the transition to the ILS.