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Flying A-NAV SIDS and STARS RNAV

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Is it possible to fly A-NAV SIDS and STARS especially ones where you intercept a radial with RNAV equipment?  Thanks.

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I'm not familiar with A-NAV as an acronym, but I'm assuming you mean conventional navigation.

 

If so, absolutely, but you must have the relevant navaids tuned, identified and displayed and use them to confirm you are tracking correctly.

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This may or may not be confused with the acronym RNAV (area navigation) substituted with "A-NAV" which in theory would make more sense  :huh:

 

I'm not familiar with A-NAV as an acronym, but I'm assuming you mean conventional navigation.

 

If so, absolutely, but you must have the relevant navaids tuned, identified and displayed and use them to confirm you are tracking correctly.

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This may or may not be confused with the acronym RNAV (area navigation) substituted with "A-NAV" which in theory would make more sense  :huh:

"Area navigation used to be called "random navigation", hence the acronym RNAV"

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What I mean is can I fly non-RNAV SIDS and STARS with FMC or GPS, where you have to intercept radials?  Sorry that A-NAV confused you.  

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No problem, that's what I thought you meant -- as I say, you can but you must tune, identify and display the raw data as well, and use it to confirm your tracking (so, for instance, if a procedure requires you to track outbound on the 075 radial from the XYZ VOR you can use the FMC to fly the procedure in LNAV but you must also tune and identify the XYZ VOR and display the needles to confirm that you are in fact tracking along the 075 radial).

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Skelsey's  point about the requirement for raw data to be presented is absolutely correct. If the procedure requires a VOR, you must have that radio frequency tuned to confirm your position. That said, many FMCs (and even Garmin GPS units) have a neat trick where they can create custom GPS-derived waypoints based on radio aids. So for instance if you wanted to created a custom position 5nm out on the 256 radial of the SLI VOR, you would enter SLI256/05 into the FMC. If you placed SLI as the next waypoint you would essentially be intercepting the VOR at radial 256, from a 5nm DME arc, and flying inbound. You can't rely solely on the GPS, however. Radio based procedures require tuning the VOR. You can drive the autopilot by GPS, but the data from the actual radio beacon must be present. 

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That's makes sense.  Do you know if it's possible to do this with the default FSX GPS?  Thanks.

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Unfortunately, the default GNS 530 is not capable of creating user waypoints. The RXP GNS 530 and the Flight1 GTN 750, however, are modeled extremely accurately, and do have this capability. They can both use a VOR radial/distance or latitude/longitude as the reference. 

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That's too bad.  The only thing that comes to mind is to use either the FSX flight planner or something like Plan-G to create a user waypoint.  Thanks.

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Skelsey's  point about the requirement for raw data to be presented is absolutely correct. If the procedure requires a VOR, you must have that radio frequency tuned to confirm your position

 

At least in the US, that's actually only true for approach procedures, and only then when inside the final approach fix, and only for the primary navaid.. From the AIM, 1-2-3 Use of Suitable Area Navigation (RNAV) Systems on Conventional Procedures and Routes 

 

a. Discussion. This paragraph sets forth policy, while providing operational and airworthiness guidance regarding the suitability and use of RNAV systems when operating on, or transitioning to, conventional, non−RNAV routes and procedures within the U.S. National Airspace System (NAS):

 

1. Use of a suitable RNAV system as a Substitute Means of Navigation when a Very−High Frequency (VHF) Omni−directional Range (VOR), Distance Measuring Equipment (DME), Tactical Air Navigation (TACAN), VOR/TACAN (VORTAC), VOR/DME, Non−directional Beacon (NDB), or compass locator facility including locator outer marker and locator middle marker is out−of−service (that is, the navigation aid (NAVAID) information is not available); an aircraft is not equipped with an Automatic Direction Finder (ADF) or DME; or the installed ADF or DME on an aircraft is not operational. For example, if equipped with a suitable RNAV system, a pilot may hold over an out−of− service NDB.

 

2. Use of a suitable RNAV system as an Alternate Means of Navigation when a VOR, DME, VORTAC, VOR/DME, TACAN, NDB, or compass locator facility including locator outer marker and locator middle marker is operational and the respective aircraft is equipped with operational navigation equipment that is compatible with conventional navaids. For example, if equipped with a suitable RNAV system, a pilot may fly a procedure or route based on operational VOR using that RNAV system without monitoring the VOR.

Emphasis mine. 

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^^^ this is true. I'm currently working with a 777 pilot from a large Gulf airline and there is no requirement to tune or monitor a VOR on a VOR approach as the aircraft derives its position without the ground aid.

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^^^ this is true. I'm currently working with a 777 pilot from a large Gulf airline and there is no requirement to tune or monitor a VOR on a VOR approach as the aircraft derives its position without the ground aid.

 

Again, at least in the US, that's not correct. As per AC 90-108, RNAV cannot substitute for conventional navaids that provide lateral guidance on the final approach segment, or localizer based navaids. This means that for a VOR or ADF approach the raw data must be displayed and monitored. However, this does not mean the autopilot has to be coupled to them (which is what I assume your contact was getting at). For instance, using CRJ procedures at a major US regional, you'd have the PM go green needles as you were getting vectors. The PF would stay white needles and the flight director would be coupled to the FMS for lateral guidance. The PM would monitor the raw data throughout the approach, fulfilling the regulatory requirement. 

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We require the raw data to be displayed at the organization I fly for, yet we allow the FMS to still handle the navigation. We put the VOR up as a second needle on our EHSI so we can reference it. This is regulation based.

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