Flight Plan Amendment with GTN 750

the400kid

the400kid

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I'm relatively new to the GTN and was wondering the proper way to handle amendments.

Let's say for example that I'm on a flight plan from KPSC with the routing SUNED, GUBSE, BTG direct KHIO.

I'm between SUNED and GUBSE when ATC calls "Cessna 123X, I have an amendment to your flight plan. Following GUBSE join Victor 448 to Battle Ground direct.

My question is, with the original flight plan already programmed, how should the routing be changed to reflect intercepting V448?
 
You would open the flight plan page, tap GUBSE, select "add after", enter the VOR and then "load airway". Page 32 of the cockpit reference guide.
 
cheap weenie said:
You would open the flight plan page, tap GUBSE, select "add after", enter the VOR and then "load airway". Page 32 of the cockpit reference guide.
Click to expand...

When I do that in the simulator, by adding YKM (the GTN needs to VOR's in order to load an airway) after GUBSE and then loading airway (V448), it's taking me up to YKM from GUBSE. The ATC instruction was to "join".
 
In that situation, I would possibly use the rubber-banding feature on the map page. First, make sure airways are turned on in the Map Overlays....then once you start to drag the map, an option to graphically edit FPL appears. Select that then adjust the route. Done.

Your MEA would then become 14,500!
 
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Why do you need the GTN to show your exact course?

Insert YKM V448 BTG. Fly a HEADING to intercept.

Unless GUBSE were on V448, the heading must be part of your intercept clearance. If it isn't, make one up (say, 260) and read it back.

The MEA isn't always the lowest altitude. You can be vectored below it. Though V448 goes right over Mt. Adams, so that's not very likely.
 
What about joining V448 at ANGOO?
 
the400kid said:
What about joining V448 at ANGOO?
Click to expand...
Then your amended clearance would contain ANGOO.

You MUST learn how to intercept an airway with a GPS. It's really not hard unless you insist the magenta line shows your actual ground track at all times.

Approaches with this will blow your mind otherwise.
 
the400kid said:
When I do that in the simulator, by adding YKM (the GTN needs to VOR's in order to load an airway) after GUBSE and then loading airway (V448), it's taking me up to YKM from GUBSE. The ATC instruction was to "join".
Click to expand...

You would intercept the airway just like you would if you were actually tracking the VOR instead of using GPS. Fly an appropriate intercept course and wait for the needle (and magenta line) to center.
 
Not really a clearance you should get. GUBSE direct [simco, oxnas, angoo, learn, ojumu] V448 BTG rest of route unchanged is valid. After GUBSE fly heading [something kinda westerly] join V448 BTG is likely. Exactly what buttons you push in a 750 I ain't got a clue. That rubber banding feature sounds cool. No more click, click, click, click.................................enter. Sheet, I missed one click, ok here we go again, click, click, click, click.............................................
 
Atc isn't going to give you an airway to join without a heading or a waypoint to join at. If a waypoint, just insert it into your flight plan. If it's a heading, add a waypoint further back along that airway and fly the heading until the airway is intercepted. In your case add Yakima then Angoo then then add the airway to angoo. Activate the leg, and intercept.
 
Can't you select the VOR and use OBS function, I believe if you have GPSS it will intercept the magenta line automatically.
Note to self, try this next flight.
 
teejayevans said:
Can't you select the VOR and use OBS function, I believe if you have GPSS it will intercept the magenta line automatically.
Note to self, try this next flight.
Click to expand...
Sure, if you don't mind being off course by up to 6 deg.

Look up VOR twist. VOR radials are not exactly equal to courses.

The GTN series support airways, and it's kinda silly not to use them. If you have an older GNS, you'll need to enter BOTH VORs plus any bends.

If you have a nav capable autopilot, you'll have to arm the nav mode and fly a heading.
 
There is not a way to program a heading as an airway entry point. That would be really cool, but not currently a feature. Fly the given heading and try to survive, until you intercept the airway, without the magnets line.
Like Makg1 said, it's a simple hdg with nav intercept if you are using an AP.
 
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You can create a user waypoint via VOR radial and DME (miles) from and then add that to your flight plan. You'd have to get those off of the enroute chart the old fashioned way (measure the miles using tics) etc. Probably more trouble than its worth, but doable if you have a copilot who knows how to do it.
 
coloradobluesky said:
You can create a user waypoint via VOR radial and DME (miles) from and then add that to your flight plan. You'd have to get those off of the enroute chart the old fashioned way (measure the miles using tics) etc. Probably more trouble than its worth, but doable if you have a copilot who knows how to do it.
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I've yet to see a user waypoint specified by a VOR radial. Courses, sure, but that's not the same.

I estimate VOR twist of 4 deg off YKM. That won't get you a violation at the distances involved THIS time, but it might get you a WTF from Center if you turn inbound more than a mile off center.

Why is there so much resistance to flying a heading to intercept? That's how it's done.
 
This is for the Garmin 430, but others are similar:
7.11 USER WAyPOINT PAGE
In addition to the airport, VOR, NDB, and intersection
information contained in the Jeppesen NavData Card,
the GNS 430 allows the pilot to store up to 1,000 user-
defined waypoints. The User Waypoint Page (Figure
7-37) displays the waypoint name (up to five characters
long), identifier, radial from two reference waypoints, and
distance from one reference waypoint, along with the user
waypoint' s latitude/longitude position.
 
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coloradobluesky said:
This is for the Garmin 430, but others are similar:
7.11 USER WAyPOINT PAGE
In addition to the airport, VOR, NDB, and intersection
information contained in the Jeppesen NavData Card,
the GNS 430 allows the pilot to store up to 1,000 user-
defined waypoints. The User Waypoint Page (Figure
7-37) displays the waypoint name (up to five characters
long), identifier, radial from two reference waypoints, and
distance from one reference waypoint, along with the user
waypoint' s latitude/longitude position.
Click to expand...
Yes. And if you assume the course from a VOR (which is what Garmin means in this context) is equal to a radial as published on the chart, you will fly to the wrong place.

If you're going to roll your own procedure, you have to understand what the pieces do in detail. You will make a user waypoint that looks like it's on the airway, but isn't.

And have you actually tried this? The workload is a LOT higher than just flying a damn intercept.
 
MAKG1 said:
Yes. And if you assume the course from a VOR (which is what Garmin means in this context) is equal to a radial as published on the chart, you will fly to the wrong place.

If you're going to roll your own procedure, you have to understand what the pieces do in detail. You will make a user waypoint that looks like it's on the airway, but isn't.

And have you actually tried this? The workload is a LOT higher than just flying a damn intercept.
Click to expand...

I think the point is that you can use radial and distance to ESTABLISH the user Waypoint. It could be a radial and distance from some point a 1000 miles away if you knew that that was exactly where the point is you were establishing. Once that was done, now you could just go Direct to the User Waypoint you just established. You could even use the OBS button to fly to the newly established Waypoint via a particular course that you wanted to. Of course you would probably use a radial and distance from the VOR that defines the Airway you were establishing a "roll your own" fix on.
 
luvflyin said:
I think the point is that you can use radial and distance to ESTABLISH the user Waypoint. It could be a radial and distance from some point a 1000 miles away if you knew that that was exactly where the point is you were establishing. Once that was done, now you could just go Direct to the User Waypoint you just established. You could even use the OBS button to fly to the newly established Waypoint via a particular course that you wanted to. Of course you would probably use a radial and distance from the VOR that defines the Airway you were establishing a "roll your own" fix on.
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Actually, no it can't. The distance field won't go over 99 miles.

I've used distance/course user waypoints to establish photo grids. I'm quite familiar with them. It's also a trick for defining a search pattern across a known course (using the distance and XTE fields) when a SAR package is not available.

The context here is to find a point on the airway. Conveniently, the radial defining the airway is printed on the chart. But that's what you dial into a VOR, and it is NOT equal to the course.
 
MAKG1 said:
Actually, no it can't. The distance field won't go over 99 miles.

I've used distance/course user waypoints to establish photo grids. I'm quite familiar with them. It's also a trick for defining a search pattern across a known course (using the distance and XTE fields) when a SAR package is not available.

The context here is to find a point on the airway. Conveniently, the radial defining the airway is printed on the chart. But that's what you dial into a VOR, and it is NOT equal to the course.
Click to expand...

Ah. 99 miles is the limit. That makes sense. I was going with the context of creating a User Defined Waypoint. Creating one that you could then fly to. Of course if you were trying to Create one where you are right now, and you were using a VOR to figure out where you are right now, then the +/- 4 or 6 degrees error is going to be a factor.
 
luvflyin said:
Ah. 99 miles is the limit. That makes sense. I was going with the context of creating a User Defined Waypoint. Creating one that you could then fly to. Of course if you were trying to Create one where you are right now, and you were using a VOR to figure out where you are right now, then the +/- 4 or 6 degrees error is going to be a factor.
Click to expand...
No, the VOR receiver error is not the issue.

Break out a chart and plotter, and measure the course from the station defining an airway. Then look at the labeled radial. They are not the same.

Magnetic declination changes on the order of a degree per decade, worse the closer you get to the magnetic pole. A VOR several decades old is misaligned with magnetic north by several degrees. Airway definition includes this. The charts are labeled to compensate for it. But your GPS isn't because it only applies to VORs.
 
Ah. Got it. I remember the explanations now of why the "desired track" seems a little off sometimes.
 
MAKG1 said:
Actually, no it can't. The distance field won't go over 99 miles.
Click to expand...

I just constructed a user defined waypoint using the 400/500 trainer at KBIH using DRK. It was over 300 miles away. Worked fine.


DRK 286.9 radial, 327.9 n.m. N 37 22 23.2, W 118 21 49.0

Than I relocated to DRK and set up direct KBIH: 328 miles.
 
MAKG1,

As long as one uses a VOR as the "active waypoint" a GPS will use the VOR declination and not the current variation. That has the effect of lining up the white/magenta line with the radial to within 1 degree. The same is true if you enter a user waypoint, the value is a radial as defined by the VOR alignment. However, this does not apply to a course to a waypoint or airport, as the current variation is used by the GPS.
 
John Collins said:
MAKG1,

As long as one uses a VOR as the "active waypoint" a GPS will use the VOR declination and not the current variation. That has the effect of lining up the white/magenta line with the radial to within 1 degree. The same is true if you enter a user waypoint, the value is a radial as defined by the VOR alignment. However, this does not apply to a course to a waypoint or airport, as the current variation is used by the GPS.
Click to expand...
OK. Is that any GPS, or just Garmin panel mounts?

It doesn't seem to be the way Foreflight behaves, for instance (but they also seem to have fairly large rounding errors). And there still seem to be a lot of Apollo and King GPSs around.

I've made a lot of user waypoints, but never in direct reference to a VOR.

Even so, it sure seems like a lot of work compared to just intercepting an airway bracketed by two VORs, on a heading.
 
I think it is for panel mounts, certainly after WAAS, it is part of the TSO.

As far as ForeFlight is concerned, if you specify a radial/radial or radial/distance with respect to a VOR, the location of the point is based on the VOR declination. As an example, on ForeFlight, enter the route CLT/232/32 to CLT093/CTF349. This should generate a route between LOCKS intersection and LOCAS intersection. Then drag the route to the CLT VORTAC and you will see it falls along V54 to the east and connects to V454 on the 232 radial of CLT. The magnetic CRS will be based on the current variation, but the magenta line will align with the radial. You have to set the date forward a few days on ForeFlight and go to display the route log to see the no-wind CRS. The point is that you set your CDI to the radial on the chart, but you will find yourself tracking the CRS value on a no wind day to keep the needle centered.

What is described above only works when you are setting a point based on the location of a VOR, otherwise the point relative to a Non VOR waypoint or NDB will use the current variation for plotting the location of the fix. It all has to do with setting an OBS radial for the CDI and flying a course that keeps the needle centered. Most likely what you are referring to large rounding errors is when winds aloft are taken into account and a magnetic HDG is displayed in the NavLog rather than the magnetic CRS.

It may be a lot of work for a GNS530W, but it is childsplay for the GTN. If you have a FlightStream 210 with a GNS530W, and using ForeFlight to rubber band the route, then send to the GNS530W, it is back to childsplay.
 
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