RNav and GPS Approches

[InsyleM]

What is and how do you do an RNAV and GPS Approch?
I was going to ask this in the Rnav discussion in Outer Marker, however
I figured If I post here, other people may benifit from the wisdom :)

And since you dont have an RNAV in FSX? How would you do an FSX Rnav approch? Use the GPS Display? If so then whats the diffrence between that and a GPS approch?

I Know GPS can give you altitude,
but I dont think RNAV can.
-Jonathan

[tigisfat]

What is and how do you do an RNAV and GPS Approch?
I was going to ask this in the Rnav discussion in Outer Marker, however
I figured If I post here, other people may benifit from the wisdom :)

And since you dont have an RNAV in FSX? How would you do an FSX Rnav approch? Use the GPS Display? If so then whats the diffrence between that and a GPS approch?

I Know GPS can give you altitude,
but I dont think RNAV can.
-Jonathan

RNAV is a generic term for area navigation. It describes navigational systems that can be used not just on approved airways and approaches. GPS is RNAV, so you can consider FSX as having RNAV. An RNAV approach means that it is open to all kinds of approved IFR RNAV, and a GPS approach means just that; only approved IFR GPS. Until recently, all RNAV and GPS approaches were non precision approaches, that is, without vertical guidance.

A non-precision approach simply guides you to a missed approach point through a series of waypoints and step-downs in altitude. Once you've reached that missed approach point, you have to try again, but you can hang out at that low altitude for a little while if you get down after the last waypoint quick enough. This is different from ILS and precision approaches with vertical guidance which aim to place you coming down a specific vertical and lateral path to one point, decision height, where you must go around immediately if you can't see the runway.

GPS approaches can be found in FSX by (on the GPS) selecting PROC page, select approach, (then select your approach), activate approach. selecting FLT PLN a few times should bring you back to the map screen. Be careful when selecting your transition, because there is usually a waypoint for every direction of arrival. Find these waypoints ahead of time on the main map screen.

To use them with the correct altitudes, you must download the approach plate online at a source like aopa.org. The GPS will display the plan view of the GPS/RNAV approach just like the plate, and all the waypoints are just like in real life with correct names and locations.

[stuarty1874]

Can I jump in here and ask a few questions? I'm a newbie and trying to understand GPS and GPS approaches.

I'm flying my Learjet from Edinburgh to Glasgow using GPS.
Before I depart Edinburgh I configure my GPS with Glasgow EGPF
I set my Speed
I set my Altitude
I take off
I enable auto pilot
I enable GPS and press NAV and the GPS takes over.
The AP then fly's me to Glasgow

When I'm about 15 miles from Glasgow I configure my approach in GPS
I pres PROC
I select runway ILS 5
I'm then asked to supply a way point (Vectors, GLW ot GOW)?
I'm not sure which one I should choose... so I choose GLW.
I then activate the approach in GPS

AP then continues to fly me towards the approach.

I then see the green approach paths marked on the GPS, and when I'm directly above the approach path I select APPROACH on the Learjet panel.

Should I then be automatically guided to the runway? Should the aircraft descend automatically?

The reason I ask is that it doesn't appear to.

[deepsea345]

stuarty1874, you need to program the ILS frequency to the nav 1 radio for the autopilot to fly down to the runway:

steps:

15 miles from Glasgow, configure approach in GPS
pres PROC
select runway ILS 5 (find it using the map [in flight, or while flight planning])
supply a way point (Vectors, GLW ot GOW) choose any, depending on how you want your approach
tune ILS freq. on NAV1 and turn on the NAV1 Ident
I then activate the approach in GPS
when you hear the Ident code (morse code), switch NAV/GPS to NAV and arm (press) the APP (approach) button (tip, make sure you are below the Glideslope: try 2,500 ft. AGL)
when you are on the glideslope, the autopilot will automatically disengage ALT. Hold
follow to the runway

don't forget flaps, gear, ATC clearance, etc...

[stuarty1874]

stuarty1874, you need to program the ILS frequency to the nav 1 radio for the autopilot to fly down to the runway:

steps:

15 miles from Glasgow, configure approach in GPS
pres PROC
select runway ILS 5 (find it using the map [in flight, or while flight planning])
supply a way point (Vectors, GLW ot GOW) choose any, depending on how you want your approach
tune ILS freq. on NAV1 and turn on the NAV1 Ident
I then activate the approach in GPS
when you hear the Ident code (morse code), switch NAV/GPS to NAV and arm (press) the APP (approach) button (tip, make sure you are below the Glideslope: try 2,500 ft. AGL)
when you are on the glideslope, the autopilot will automatically disengage ALT. Hold
follow to the runway

don't forget flaps, gear, ATC clearance, etc...

Good man. Worked a treat

[deepsea345]

Good man. Worked a treat

glad to help!:)