Another approach to consider: VOR/DME RNAV

Troy Whistman said:
This approach has BOTH VOR/DME and RNAV in the title... I don't recall seeing that before. Does that mean you can't fly it with GPS alone, unless you also have VOR/DME equipment?

http://204.108.4.16/d-tpp/0504/05070VDR33.PDF

Troy

Since the approach title contains neither "... or GPS" nor "GPS RNAV", it means you can't fly the approach at all using GPS as the sole navigation means, nor, for that matter, may you legally fly the approach with simple VOR & DME equipment. The aircraft must be equipped with IFR approach mode approved VOR/DME RNAV equipment in order to legally fly this approach. If you pulled this approach out of a GNS430 database, for example, the GNS430 would display "GPS for information only" (or whatever the actual warning wording Garmin chose). For those who haven't seen a VOR/DME RNAV box the equipment essentially moves a VOR/DME station a radial/distance as entered by the pilot. The radial/distances are shown plotted at each waypoint. As an example, the FAF is 112.3 (GGG) 87.9 degree radial at 26.4 DME. The user would tune the NAV to 112.3 (GGG), enter 87.9 into the "radial" window and 26.4 into the "distance" window, and select "APPROACH" on the mode selector. The VOR/DME RNAV would then alter the NAV display and DME reading so that they would function as if the VOR/DME station was located on the FAF.

I have a KN74 VOR/DME RNAV in my Mooney. I use it to obtain direct navigation much as folks use GPS. The advantage of the VOR/DME box is that it is IFR enroute and approach approved without the $400-800 annaul database update costs of any IFR approved GPS receiver. The disadvantage of the box is that AOPA long ago sold out to the GPS box manufacturers and AOPA has for quite some time allowed the FAA to selectively abandon VOR/DME RNAV approaches without any objection at all.
 
Ed Guthrie said:
Since the approach title contains neither "... or GPS" nor "GPS RNAV", it means you can't fly the approach at all using GPS as the sole navigation means, nor, for that matter, may you legally fly the approach with simple VOR & DME equipment. The aircraft must be equipped with IFR approach mode approved VOR/DME RNAV equipment in order to legally fly this approach.

Excuse me while I slap myself on the forehead....

<SLAP!!>

Duh, I knew that!! Thanks for reminding me.

Troy
 
Troy Whistman said:
Excuse me while I slap myself on the forehead....

<SLAP!!>

Duh, I knew that!! Thanks for reminding me.

Troy

I would have dragged out my demeaning humor bucket, but you fly a Mooney...:)
 
Ed Guthrie said:
The advantage of the VOR/DME box is that it is IFR enroute and approach approved without the $400-800 annaul database update costs of any IFR approved GPS receiver.

A nice advantage, indeed!!

Ed Guthrie said:
The disadvantage of the box is that AOPA long ago sold out to the GPS box manufacturers and AOPA has for quite some time allowed the FAA to selectively abandon VOR/DME RNAV approaches without any objection at all.

We had a KNS-80 RNAV in the Turbo Mooney the club had (just sold it). Same deal.

What do you mean by "AOPA long ago sold out to the GPS box manufacturers"? Did they accept some funds we don't know about? Or are you just referring to a philosophical stance they've taken? Have you expressed to them your displeasure that they aren't challenging the removal of these approaches? I'd be interested in what they've said. I think you're right that they [the approaches] should be kept around while the equipment is still in common use.
 
Troy Whistman said:
What do you mean by "AOPA long ago sold out to the GPS box manufacturers"? Did they accept some funds we don't know about?

Check the AOPA magazine advertisers and what they peddle.

Or are you just referring to a philosophical stance they've taken?

I am referring to the total lack of request for member comments and the total lack of concern on the part of AOPA, plus the obvious financial conflict. How much to you suppose King, Garmin, et al contribute to the AOPA coffers?

Have you expressed to them your displeasure that they aren't challenging the removal of these approaches? I'd be interested in what they've said.

~10-14 years ago when I noticed the trend I broached the subject at several levels within AOPA. In all cases the response was either polite silence or a facial expression one would experience after committing flatulence in church.

I think you're right that they [the approaches] should be kept around while the equipment is still in common use.

I agree. Furthermore, I'd be interested in knowing how many IFR VOR/DME RNAV installations there are versus IFR GPS installations. I went for many years only knowing of the one VOR/DME RNAV installation in my Mooney, but lately I have seen as many VOR/DME RNAV boxes as I've seen GPS boxes.
 
Ed Guthrie said:
Furthermore, I'd be interested in knowing how many IFR VOR/DME RNAV installations there are versus IFR GPS installations. I went for many years only knowing of the one VOR/DME RNAV installation in my Mooney, but lately I have seen as many VOR/DME RNAV boxes as I've seen GPS boxes.
I am in the process of buying into a Cardinal with a KNS-81 coupled to a HSI, and a VFR-only Trimble GPS, hoping to do my instrument training in that.

The RNAV also has other nice uses besides approaches - such as putting a waypoint over the center of a TFR, or an airport for which the GPS database still has only the old ID, the one that no one remembers...

Liz
 
Liz, just be sure to rememeber that which DME the DME is locked onto- it can be uncoupled from teh active display and will hang on an old VOR until it loses it....
 
Ed Guthrie said:
I have a KN74 VOR/DME RNAV in my Mooney. I use it to obtain direct navigation much as folks use GPS. The advantage of the VOR/DME box is that it is IFR enroute and approach approved without the $400-800 annaul database update costs of any IFR approved GPS receiver. The disadvantage of the box is that AOPA long ago sold out to the GPS box manufacturers and AOPA has for quite some time allowed the FAA to selectively abandon VOR/DME RNAV approaches without any objection at all.

Before you get all sentimental about the slow disappearance of Rho-Theta RNAV approaches, consider that the mins for the VOR/DME RNAV at ASL are 644-1 vs 434-1 for the GPS approach to the same runway. And having flown both R-T and GPS approaches, I strongly prefer GPS, even if it does cost me an extra $300 or so per year. And on that note, I do keep hoping to see the day when GPS DB updates are downloaded automatically via satellite from free government sources. The notion that we should have to pay a private corporation (Jeppesen) to massage the government supplied data into a form that the avionics manufacturers can use makes as little sense to me as the current nonsense about prohibiting the government from suppliying weather data.

Personally, I don't see that AOPA has "sold out" to any avionics manufacturers. I believe their position WRT R-T approaches if they actually have one would be based on what the majority of their members want and I doubt very much that the majority are pushing for R-T over GPS approaches.

Ed, I get the feeling that if you were flying IFR 50+ years ago you would be pushing for the continuation of four-course ranges and approaches so you wouldn't have to upgrade to one of those "newfangled" ADF's! :)
 
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azure said:
I am in the process of buying into a Cardinal with a KNS-81 coupled to a HSI, and a VFR-only Trimble GPS, hoping to do my instrument training in that.

The RNAV also has other nice uses besides approaches - such as putting a waypoint over the center of a TFR,

You can do that with any GPS as well, and some will even plot the circle on the moving map.

or an airport for which the GPS database still has only the old ID, the one that no one remembers...

Of course if you had an IFR GPS with current DB the new ID would be there.:)

One thing to remember WRT Rho-Theta RNAV is that to be legal you need to calculate and file waypoints along the route which are within the service volume of the referenced VOR's. A lot of pilots skip this step and rely on their VFR GPS for actual course guidance. Chances are you can get away with this indefinetly as long as it doesn't result in your straying into a conflict of some sort.
 
bbchien said:
Liz, just be sure to rememeber that which DME the DME is locked onto- it can be uncoupled from teh active display and will hang on an old VOR until it loses it....
Hi Bruce, are you referring to the DME Hold feature by any chance? So far I have not had occasion to use it - but could get into it accidentally for sure, switching the DME selector from Nav1 to Nav2 and back (center position is HLD). I *try* to cross check all readings whenever possible, but I'm sure I will screw myself up good at some point during the IR training when the workload is high.

Liz
 
lancefisher said:
And having flown both R-T and GPS approaches, I strongly prefer GPS, even if it does cost me an extra $300 or so per year.

This is all in jest, right? Okay, then:

Did you add that GPS box to an existing airframe? Better add cost of capital (interest or lost income) plus depreciation for the $8000-$10000 acquisition cost to that $300. Probably closer to $1000 per year if you do the accounting any where near accurately. How often do you use that extra 200'? Maybe once every other year or so? $2000 grand to make the intended airport versus an alternate? Whew. Your time is valuable.:)

Personally, I don't see that AOPA has "sold out" to any avionics manufacturers. I believe their position WRT R-T approaches if they actually have one would be based on what the majority of their members want and I doubt very much that the majority are pushing for R-T over GPS approaches.

That logic is why I pondered the question of how many VOR/DME RNAV equipped aircraft there might be. Could very well be that the existing fleet is better served by VOR/DME RNAV versus GPS approaches. I don't know. What I do now is that no one asked, no one knows for certain, and no one seems to care.

Ed, I get the feeling that if you were flying IFR 50+ years ago you would be pushing for the continuation of four-course ranges and approaches so you wouldn't have to upgrade to one of those "newfangled" ADF's! :)

Nope. I'd be lamenting the fact that the skill of IFR (I follow roads) was vanishing with the introduction of these new fangled instruments procedures.:)
 
lancefisher said:
You can do that with any GPS as well, and some will even plot the circle on the moving map.

I know you can do it with the Trimble too, but it's more tedious IMO (no moving map either, I'm afraid :() And you have to keep switching between NAV mode and WPT mode. It just seems easier to use the GPS with the HSI to navigate, and DME from the waypoint on the KNS-81 to stay comfortably outside the TFR.

Of course if you had an IFR GPS with current DB the new ID would be there.
:) And if one of us wins the Lotto, maybe we'll get one. :)

Liz
 
Ed Guthrie said:
This is all in jest, right? Okay, then:

Did you add that GPS box to an existing airframe? Better add cost of capital (interest or lost income) plus depreciation for the $8000-$10000 acquisition cost to that $300. Probably closer to $1000 per year if you do the accounting any where near accurately. How often do you use that extra 200'? Maybe once every other year or so? $2000 grand to make the intended airport versus an alternate? Whew. Your time is valuable.:)

Now Ed, you know it's against the rules to make any attempt to account for the cost of flying and/or justify said cost. The true purpose of the airplane and anything in the panel isn't to save time, it's to enjoy and (attempt to) master.
 
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