Victor Airways in Clearance

"Ron Rosenfeld" wrote in message =
...
On Thu, 15 Jan 2004 23:14:05 -0800, "C J Campbell"
wrote:
=20

"Ron Rosenfeld" wrote in message
.. .
| On Wed, 14 Jan 2004 10:18:44 -0800, "C J Campbell"
| wrote:
|
| It would be even easier if some genius would put the airways into =
the
| database so you could program the GPS just the way the clearance =
was
given.
|
| It is in the CNX80

I am beginning to like this unit more and more. I obviously have not =
spent
enough time playing with it.

=20
Mine is being installed as we speak. I've been reviewing the computer
aided training disk that comes with it.
=20
=20
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle =
bearing.

The manual (pg.13) implies this VOR behavior exists only for OBS mode,
but it's the case in any mode whenever a VOR is the current waypoint.

I received a private communication to the effect that they will make the
manual agree with the CNX80's behavior instead of fixing the problem.

My work-around is to create a User Waypoint at the same Lat/Lon
as any distant VOR I want to navigate toward.
I regret needing to do that.

I was told this choice was forced upon GarminAT by outside influences.
It was not the choice of GarminAT engineering.

I really hope they will find some compromise which will allow VORs
to become useful as waypoints. Right now, they are not.
Perhaps it could help if more CNX80 users told GarminAT they'd like
to navigate toward distant VORs.
---JRC---

On Sat, 17 Jan 2004 01:34:37 GMT, "John R. Copeland"
wrote:



A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle bearing.

The manual (pg.13) implies this VOR behavior exists only for OBS mode,
but it's the case in any mode whenever a VOR is the current waypoint.

I received a private communication to the effect that they will make the
manual agree with the CNX80's behavior instead of fixing the problem.

My work-around is to create a User Waypoint at the same Lat/Lon
as any distant VOR I want to navigate toward.
I regret needing to do that.

I was told this choice was forced upon GarminAT by outside influences.
It was not the choice of GarminAT engineering.

I really hope they will find some compromise which will allow VORs
to become useful as waypoints. Right now, they are not.
Perhaps it could help if more CNX80 users told GarminAT they'd like
to navigate toward distant VORs.
---JRC---

Flying mostly in the NE in a small GA airplane, I don't think that'll be a
problem, but it sure could be in other parts of the country where I could
get cleared for longer legs.

I wonder about the rationale behind that requirement. Perhaps if we ever
get "free flight" it'll be relaxed. I do like your work-around, though.

Thanks for the heads-up.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

On Sat, 17 Jan 2004 01:34:37 GMT, "John R. Copeland"
wrote:

A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle bearing.

John,

Have you noticed this statement in the approved AFM:

============================
2.4 NAVIGATION
No navigation authorized north of 89º (degrees) latitude or south of 89º
(degrees) latitude.
===========================

I know there's a missing word, but, as written, it does seem to limit its
usefulness g.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

"Ron Rosenfeld" wrote in message =
...
On Sat, 17 Jan 2004 01:34:37 GMT, "John R. Copeland"
wrote:
=20
A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle =
bearing.
=20
John,
=20
Have you noticed this statement in the approved AFM:
=20
=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D
2.4 NAVIGATION
No navigation authorized north of 89=BA (degrees) latitude or south of =
89=BA
(degrees) latitude.
=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
=20
I know there's a missing word, but, as written, it does seem to limit =
its
usefulness g.
=20
=20
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Yes, I noticed that, too.
Sometimes we just have to resort to dead reckoning.
---JRC---

Ron Rosenfeld writes:
On Sat, 17 Jan 2004 01:34:37 GMT, "John R. Copeland"
wrote:

A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle bearing.

John,

Have you noticed this statement in the approved AFM:

============================
2.4 NAVIGATION
No navigation authorized north of 89º (degrees) latitude or south of 89º
(degrees) latitude.
===========================

I know there's a missing word,

Or two missing words.

but, as written, it does seem to limit its usefulness g.

It's fine as long as you're at 89°. WTP?

I once received a call from our company's field rep saying
that some programs I'd revised weren't working correctly for
March through December. I just told him to restrict usage
to January and February. There was a long silence from the
other end of the line...

Nathan Young wrote:

On Wed, 14 Jan 2004 04:07:01 GMT, "Wyatt Emmerich"
wrote:

I fly with a Garmin 530. Great box, but I cannot for the life of me
understand why they would fail to include Victor Airways. Anyway, I often
get a clearance such as 210BA cleared to Yodoo, Clear City, Victor 245,
Bogur.

Now if I program the Garmin 530 for Yodoo, Clear City, Bogur, 19 times our
of 20 I'm fine. ATC was just throwing in the Victor 245 for--I don't
know--clarification? However, one in 20 times there's a kink in the airway
and I'll screw up if I don't check the low altitude chart.

So instead of simply programming the Garmin 530 with the waypoints, I've got
to unfold the chart, figure out where the heck I am on it and make sure
Victor 245 doesn't have a bend in the road. In real IMC involves a lot of
looking down and head movement when I would rather be focused on my scan.

My point being: It would be a heck of a lot easier for Garmin 530 users if
ATC would dispense with the airway part of the clearance and just route us
base on waypoints.

Probably a bit late, but the CNX80 can accept victor airways in its
flightplans. Hopefully Garmin will borrow this piece of code from the
CNX80 and port it to the GNS series.

-Nathan

I'll wager that the 400/430/500/530 don't have sufficient memory for airways.

wrote:

I'll wager that the 400/430/500/530 don't have sufficient memory for airways.

How much memory could it possibly take? Let's do a back of the envelope
calcultion. Assumptions:

500 airways in the country
Each airway is 1000 miles long on average
There's a waypoint every 20 miles on average.

So, you've got an average of 50 waypoints per airway times 500 airways,
equals 25,000 data points. The waypoints themselves are already in
memory, you just need references to them, say 4 bytes for a reference.
That's 100 kbytes of memory to store all the airways in the continental
US. Figure a Mbyte to store them for the entire world.

I'm typing this on a laptop with 256 Mbytes of ram. My digital camera
has the same. It's just absurd that memory limits in a $20k box should
prevent you from storing airways.

I'm not saying it's not true. Just that it's absurd :-)

Roy Smith wrote:

wrote:

I'll wager that the 400/430/500/530 don't have sufficient memory for airways.

How much memory could it possibly take? Let's do a back of the envelope
calcultion. Assumptions:

500 airways in the country
Each airway is 1000 miles long on average
There's a waypoint every 20 miles on average.

So, you've got an average of 50 waypoints per airway times 500 airways,
equals 25,000 data points. The waypoints themselves are already in
memory, you just need references to them, say 4 bytes for a reference.
That's 100 kbytes of memory to store all the airways in the continental
US. Figure a Mbyte to store them for the entire world.

I'm typing this on a laptop with 256 Mbytes of ram. My digital camera
has the same. It's just absurd that memory limits in a $20k box should
prevent you from storing airways.

I'm not saying it's not true. Just that it's absurd :-)

Then there is the issue of firmware and processor time to sort out all those
waypoints and nail them together correctly. And, where do you then place them for
a long, or complex route, when the box has a 30 waypoint limitation per flight
plan?

Also, there are many, many, mid-route airway transitions, such as V-264 joining
V-137 eastbounc, east of Ontario, California. Those all have five numbers, rather
than 5 letters, and I bet you can't find them in a 400/430/500/530.

Here is the one I mentioned, which is part of the V-264 route description in NACO's
Digital Aeronautical Information database. This waypoint would be used only for
the eastbound flight on V-264 that is cleared to transition onto V-137. That takes
some software smarts to figure all that out. Then again, a Boeing 767 was able to
perform such a sort in 1980.

V137 15419 34 05 49.8 116 54 33.5 ZLA AWY INT

SeeAndAvoid wrote:

The point of ModeS and Datalink was for this, communication-less ATC.
That's where many of the mistakes occur, readback/hearback errors. First
heard about this at least 10 years ago. But the idea was a display/printout
of a clearance, not having that clearance go directly into the GPS/FMS.
Do we really want that? Maybe after accepting it, then pasting it over into
your flight plan.

The FAA had big plans for ATC communications datalinks dating back to the late
1960s.~

On Sat, 17 Jan 2004 01:34:37 GMT, "John R. Copeland"
wrote:

A disappointment in the CNX80 is in navigating to a distant VOR.
No matter how far away, it displays the fixed inbound VOR radial,
but calls it "Bearing to Waypoint".
In truth, it becomes the bearing only when you are near the VOR.
All other types of waypoints always display the correct great-circle bearing.

The manual (pg.13) implies this VOR behavior exists only for OBS mode,
but it's the case in any mode whenever a VOR is the current waypoint.

I received a private communication to the effect that they will make the
manual agree with the CNX80's behavior instead of fixing the problem.

My work-around is to create a User Waypoint at the same Lat/Lon
as any distant VOR I want to navigate toward.
I regret needing to do that.

I was told this choice was forced upon GarminAT by outside influences.
It was not the choice of GarminAT engineering.

I really hope they will find some compromise which will allow VORs
to become useful as waypoints. Right now, they are not.
Perhaps it could help if more CNX80 users told GarminAT they'd like
to navigate toward distant VORs.
---JRC---

John,

I've finally had some time to play with my new CNX80 as well as the
simulator recently posted on their web site. And I'd like to add a few
things to your observation, and possibly a different work-around.

As I played with things more and more, I decided that I'm actually OK with
how it works!

1. As you note, the "Bearing" on Map 1 represents the final course to the
VOR. However, (I think this next is true) since VOR radials follow a great
circle route, it also represents the VOR radial (reciprocal, actually) that
you would be flying were you to be navigating to that VOR.

2. The CNX80 will still navigate along the Great Circle route. So, for
example, if I were to set up a flight plan from my home base (KEPM) to the
POMona VOR (NE of KLAX), the "Bearing" on Map 1 is 224° but my actual
course, at the beginning of the flight, will be 291°.

3. You can customize one of the other pages to show the Desired Track (DTK)
which will, indeed, be 291° when starting out.

But thanks for bringing up the point. It got me thinking about things I
might not otherwise have considered in using this box.




Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)