Flying the magenta line?

[airdale]

I am surprised at the number of pilots I've flown with as a safety pilot or just talked with whose normal mode of operation with a GPS is to just fly the little airplane along the magenta line. This for enroute and holds especially, but even on approaches.

I have always considered this to be sloppy flying at best and dangerous at worst. The accuracy depends on screen magnification, you lose over time the ability to fly using the needles, and you lose over time the ability to maintain situational awareness if the little map is not available.

The way I fly with a GPS is to use TRK, DTK, BRG, and the CDI or HSI. The Nav 1 screen on a 430. I'll occasionally switch to glance at the map as a reference but it would hardly matter to me if I lost it. This is true even in a G1000, though having that beautiful color tv with WX right there is certainly nice.

Am I out to lunch on this?

 

[TangoWhiskey]

I fly GPS as you do, with TRK, DTK, and Track offset numbers. Makes wind correction automatic, and if you fly by the numbers, you'll be "on the purple line" automatically.

 

[tonycondon]

no not really

 

[Cap'n Jack]

When I was studying for IFR, I found the projected track to be useful with the other information. I'd have the needle centered and be right on the MLOD, but the projection would show me getting ready to drift off and I could quickly correct before a large correction was required.

I just considered it another bit of information to be used and cross checked with other data, but it sure helped me stay on course.

 

[TMetzinger]

The map on the MFD is useful for "big picture" stuff (do I have a turn coming up, how big a turn, where's the terrain, where's the weather, etc), so it's definitely in my scan, but I navigate using the DTK, TRK, and XTE and the CDI. The G1000 has the little diamond that shows track on the HSI, so it's easy to put the green diamond on the course pointer or the RMI pointer and track right to/from the waypoint.

Now if you're flying VFR? maybe following the magenta line is "good enough". But not for IFR.

 

[poadeleted20]

Am I out to lunch on this?

No. And it is a disturbingly common problem.

 

[olasek]

I would have a hard time believing that an instrument rated pilot would do that as his 'primary' means of navigation, perhaps it is a misinterpretation by the observer - he is not really "following" the magent line, he may be cross checking it.

 

[Lawreston]

Good post, airdale. In my limited experience with the big toy(430-W) -- and VFR -- I'm with Tim. I like those numbers which tell me that I'm holding course or deviating by 3 or 4° for which I can readily correct.

During one flight which normally takes 25 or 30 minutes I stretched it to 1½ hours. ???????
I repeatedly veered haphazardly off-course, intentionally, for 8 or 10 minutes. That gave me the opportunity to "play" with the various pages, maps, and/or screens, sometimes being a greater distance from KIWI(destination) from where I started at another airport. I like that instrument, though the primary attention remains outside.

HR

 

[bbchien]

Man, oh man. I am old.

I remember being taught to "fly the line" which was a D.R. perpendicular to the route of flight, usually at the +30' point drawn by a dividier on a compass line.

I remember flying the line defined by a trianglular box contained between three Cnav sight fixes, defined by the perpendicular of the longest side of the triangle.

Why have aviators become the Jaywalk of the stars?!!

Shame on pilots.

 

[PilotAlan]

I am surprised at the number of pilots I've flown with as a safety pilot or just talked with whose normal mode of operation with a GPS is to just fly the little airplane along the magenta line. This for enroute and holds especially, but even on approaches.

I have always considered this to be sloppy flying at best and dangerous at worst.

Agreed.
I fly with GPS as my sole navaid, but I fly pilotage with the GPS for SA.
Anything outside of the metro area I plot the course (not GPS direct, but using airports as checkpoints) and fly pilotage and using GPS for groundspeed, SA, and ETA to destination.

 

[kevin47881]

The "magenta line of death"?

 

[Lawreston]

Let me redefine "Veered Haphazardly off-course," Bruce; as in diverting with no particular revised destination(and after appropriate clearing turns), for the express purpose of practice with both pilotage and the GPS. Said diversions were not knee-jerk alterations.

HR

 

[azure]

Good post, airdale. In my limited experience with the big toy(430-W) -- and VFR -- I'm with Tim. I like those numbers which tell me that I'm holding course or deviating by 3 or 4° for which I can readily correct.

"Me too"... I don't like staying on map page for very long. When I'm relying on the GPS for navigation it's mainly the DTK, TRK, and external CDI, so default NAV page is where I'm most comfortable. The main thing I use map page for is situational awareness w.r.t. airspace boundaries. I haven't used the VORs in the club planes much yet. That comes next, I'm still getting used to the 430 and all its quirks. The Cardinal I used to fly didn't have any kind of moving map GPS, but I felt a lot more at home in it than with all the neat modern toys I have now.

And yep, I should practice pilotage more. I used to be proud of how well I kept track of where I was visually. Those skills deteriorate over the years, gotta work on getting them back.

 

[Henning]

Man, oh man. I am old.

I remember being taught to "fly the line" which was a D.R. perpendicular to the route of flight, usually at the +30' point drawn by a dividier on a compass line.

I remember flying the line defined by a trianglular box contained between three Cnav sight fixes, defined by the perpendicular of the longest side of the triangle.

Why have aviators become the Jaywalk of the stars?!!

Shame on pilots.

Accuracy and reduced workload. First off, when you were flying Cnav, you were flying in a plane that had a 4 crew cockpit correct? Cpt, FO, FE and Nav? Now even in an airliner doing twice+ the speed of your P3 we have a 2 pilot cockpit, and I don't care how good you are with a sextant, you're not nearly as accurate as a GPS. On a really good day, my triangle of doubt on a three star running fix is about 3 miles across. Then there's the factor that there are only so many fixes available in a day. I forget, does HO 249 even give you the moon? The reduction in workload also gives us more time to monitor engine functions and fuel states. The reality is that this equipment is a lot more reliable than humans are and if you have a redundant unit with redundant emergency power to keep them running to the next available landing, following the magental line is probably safer than anything else for most people since it's not normally the nav end of things that get you in trouble, rather the systems end, running out of fuel, burning up an engine.... much of which can be avoided by being able to devote more attention to monitoring the plane rather than the path. And to all of those of you who fly IFR on Autopilot, all I have to say to that is "pot...kettle..." But I'm not knocking it. You need to be able to hand fly with a chart and a single VOR, and if you intend to fly passengers around in IMC, you should spend 1/4 of your solo IMC time doing so. But when it comes down to hauling the Pax in IMC, it's time to couple up to the magenta line and let the equipment fly the plane so you can monitor the equipment.

 

[flyingcheesehead]

Excellent points, Henning.

Personally, I like to put the 430W on the map page at 20nm (shows all details and even the smallest public fields), mainly to help in an emergency. The needle is there for keeping on course, and I will often just put the plane on autopilot in cruise and play the "find-the-private-unpaved-strip" game with a sectional. Provides even better awareness for emergencies, and keeps the eyes outside, too!

Hand-flying, I often won't even bother putting the destination into the GPS if I have a general idea where I'm going. I know southern WI pretty well from driving and flying it so much, and there are many other areas where I can recognize intersections, warehouses, truck stops, whatever that I've been to and thus know exactly where I am. Ask Pete.

 

[MikePapa]

I personally don't see why someone would want to fly an approach exclusively by the magenta line. I've actually tried this and it's not as easy as it sounds. If you don't believe it, try it sometime. Completely ignore (or better yet cover up) the DG, CDI, HSI, compass, and all over forms of lateral guidance and try flying the magenta line. It's pretty difficult, particularly on an approach past the FAF where accuracy counts, especially if you don't have a vector line option to make reasonable wind corrections.

 

[dmccormack]

Excellent points, Henning.

Personally, I like to put the 430W on the map page at 20nm (shows all details and even the smallest public fields), mainly to help in an emergency. The needle is there for keeping on course, and I will often just put the plane on autopilot in cruise and play the "find-the-private-unpaved-strip" game with a sectional. Provides even better awareness for emergencies, and keeps the eyes outside, too!

That's the ONE big improvement Garmin made to the 396/496 series over the 430 -- a single button for NRST.

It takes a few presses and scrolls to find nearest airport in the 430 (depending on what nearest fix you had in last).

As far as the GPS for primary nav -- I like having the finer resolution the DTK/TRK shows -- as others have said, 1-2 degrees off course shows up.

I do fly VOR-only from time to time to keep the trend observation eyeballs calibrated, but I'm still can't keep within 1 degree of course (47-year-old eyes, perhaps?)

Anyway, while the old school tools should be understood and used, it's wise to employ all tools when flying pax in IMC. Otherwise, why not go partial panel and disconnect the comms? In the old days it was needle, ball, airspeed.

 

[dmccormack]

I personally don't see why someone would want to fly an approach exclusively by the magenta line. I've actually tried this and it's not as easy as it sounds. If you don't believe it, try it sometime. Completely ignore (or better yet cover up) the DG, CDI, HSI, compass, and all over forms of lateral guidance and try flying the magenta line. It's pretty difficult, particularly on an approach past the FAF where accuracy counts, especially if you don't have a vector line option to make reasonable wind corrections.

Yikes... that's a definite PITA!

 

[bbchien]

Accuracy and reduced workload. First off, when you were flying Cnav, you were flying in a plane that had a 4 crew cockpit correct? Cpt, FO, FE and Nav? Now even in an airliner doing twice+ the speed of your P3 we have a 2 pilot cockpit, and I don't care how good you are with a sextant, you're not nearly as accurate as a GPS.

I'm not talking airliner here. I'm talking Cessna 182.

Last weekend I heard a guy callup Chicago Center and Loc'd himself 15 E of the Joliet VOR. He was 15 West in another sector. The guy cannot work a Vertical omnirange.

No wonder controllers regard fliv operators as "OMG" cases.

So when you get an intermittent electrical bus short, and the I-nav hits the bunker, and there are no "landmarks" for a couple three thousand miles in each direction.....your fall back is not a VOR.

GA pilots as a whole need to have the ability to work a backup navigation routine. Occasionally the magenta line wil GO AWAY. So I am increasingly concerned these last ten years that the typical Joe Pilot has NO backup routine when the magenta goes away. We see the results with some frequency- the guy has typed in the wrong identifier....

 

[wabower]

What's the BFD? They are the same guys who never knew where they were before GPS anyway. Fact is, the pilot population is heavily weighted towards the lower end. Even the guys that you think should be pretty good are often lighter than a June frost.

I think it's a fact of life and have moved on. Nothing I'm going to be able to do (nor the FAAST team or all the other erstwhile efforts) is going to change these nitwits. Darwin will claim some, mortality will do its thing, but like the poor they will be with us always.

I am surprised at the number of pilots I've flown with as a safety pilot or just talked with whose normal mode of operation with a GPS is to just fly the little airplane along the magenta line. This for enroute and holds especially, but even on approaches.

I have always considered this to be sloppy flying at best and dangerous at worst. The accuracy depends on screen magnification, you lose over time the ability to fly using the needles, and you lose over time the ability to maintain situational awareness if the little map is not available.

The way I fly with a GPS is to use TRK, DTK, BRG, and the CDI or HSI. The Nav 1 screen on a 430. I'll occasionally switch to glance at the map as a reference but it would hardly matter to me if I lost it. This is true even in a G1000, though having that beautiful color tv with WX right there is certainly nice.

Am I out to lunch on this?

 

[SCCutler]

I was fortunate enough to have an instructor on a "brush-up" flight who allowed me the "luxury" of over-using the MLOD on an approach, and I learned first-hand the inherent risk of disregarding the primary means of navigati8on. Not pretty, but very instructive. Now, the GPS' map is for general situational awareness, unless I am flying a GPS approach.

---

Yesterday, Tommy and I were flying ADS to AUS, departed into a solid cover at 1,200', top at 3,000-ish. A guy checks on with my controller's sector (wish I'd taken down his tail number), "level 9500 feet," eastbound. Yikes. There was no VMC for a couple hundred miles around.

Then he asks the controller (DFW Regional Approach), "Can you give me the ILS frequency for Gregg County..." (GGG is about an hour east). Controller replied pretty much as I expected, with "...ummm, OK, I'll see what I can do."

I wonder how that all worked out.

Cue Dr. Bruce's patented... "Sigh."

 

[Ted]

Stupid is as stupid does. There have always and will always be stupid people. Modern technology has just made it easier for stupid people to be stupid and not kill themselves off at as rapidly a rate as was once possible. That is the problem. The good part is that those of us with intelligence levels higher than a duck (once of the less intelligent creatures I have come across) can use these tools to our advantage.

To me, the magenta line is another good tool to help situational awareness. That said, I never fly it. I'm continuously flying my CDI, whatever I happen to have that tuned to. The handheld GPSs are good tools as well. The AnywhereMap I recently bought has a feature in it that will give you a virtual ILS that you program in. Last night I tried it out coming into Williamsport on a perfectly clear night to test it. Sure enough, it works pretty nicely. I like it. I would never under any circumstances fly it instead of a real ILS. I would, however, use it to get me on the ground if I had a complete electrical failure in the soup and that was my only good means of getting back on the ground. The way it's programmed, you can program it with the characteristics of the real ILS, making it very close to the real thing.

 

[airdale]

I would have a hard time believing that an instrument rated pilot would do that as his 'primary' means of navigation, perhaps it is a misinterpretation by the observer - he is not really "following" the magent line, he may be cross checking it.

Nope. There is not, of course, a bright line between using the map for SA and flying the magenta line, but people really do fly the line. And, btw, the latest situation that prompted the post was a CFII who became quite annoyed when I "failed" his map while on the initial leg of an RNAV tee approach.

I am not a nazi about this either. When flying a 430 I'll sometimes flip from NAV1 to NAV2 for SA, but there have also been flights where I was on NAV1 flying TRK and CDI for 100% of the time. As someone said, the map another tool in the kit.

... when it comes down to hauling the Pax in IMC, it's time to couple up to the magenta line and let the equipment fly the plane so you can monitor the equipment.

Agree. When I'm practicing I hand fly and when its for real I use the AP if one is available. BTW when I talk about flying the magenta line I am not talking about using the AP to do it. I am talking about hand flying.

I personally don't see why someone would want to fly an approach exclusively by the magenta line. I've actually tried this and it's not as easy as it sounds.

I haven't seen exactly that and certainly it would not be all that easy if you had the magnification set so that the little airplane's deviations were clear, because then the critical waypoints would not be visible. But I have seen people fly holds from the map.

... TRK, DTK, and Track offset numbers. Makes wind correction automatic, and if you fly by the numbers, you'll be "on the purple line" automatically.

Yes, and what is not immediately apparent to some people is that flying the CDI or the magenta line you can't take action until you see an off-course situation. Flying TRK, you see the problem before you actually go off-course by any significant amount. Flying a localizer I keep one eye on TRK, one on the needle, and one on the heading bug, which I set to whatever heading seems to be making TRK work out.

<thread drift>

It takes a few presses and scrolls to find nearest airport in the 430 (depending on what nearest fix you had in last).

Actually not. Assuming the cursor is not active, just give the big knob a spin to the right and the little knob a spin to the left -- without looking at the screen. Same-o to return to the NAV/MAP 1 page, spin 'em both to the left. I believe this is why the knobs don't "roll over" at the ends of the chapter and page lists and also why the less-important chapters are in the middle of the chapter list. Thoughtful designers.
</thread drift>

 

[Palmpilot]

Lately I have taken to flying approaches in VMC, because even if I can't log it due to the lack of a hood and safety pilot, I feel that it contributes to proficiency, especially with GPS approaches, which I don't feel confident with yet. This paid off a few days ago when it exposed a potentially fatal weakness in my knowledge of the 430.

I was trying to fly the Palo Alto GPS approach, and had been given direct DOCAL (an IF), and cleared for the approach.

http://www.naco.faa.gov/d-tpp/0911/09216G31.PDF

After passing DOCAL, it was clear from the hillside in front of me, as well as the calls from ATC, that I was getting seriously off course, although the CDI was reasonably centered, so I abandoned the approach and went back for another try to figure out what went wrong. It turned out that the problem was caused by loading the approach without activating it.

After I got home, I looked through the manual to find out what would be the indications on the GPS screen of an approach not having been activated. This was a subject of vital interest to me, since in IMC I would not have the advantage of being able to see the hillside in front of me. One thing I found is the statement that "the active leg of the flight plan always appears in magenta." During the flight, the course line ahead of me was white after passing DOCAL on the first attempt, so that would have been an obvious indication that something was wrong. The white line in front of me was merely the entension of the course I had flown while I was inbound to DOCAL.

So for that reason I think there are lots worse things than flying the magenta line, although it obviously should be combined with monitoring the CDI, especially on approaches.

No doubt there are other ways of detecting that an approach has not been activated. For example, I would expect that the next waypoint on the approach would not be displayed, although I didn't notice whether this was the case during the flight.

 

[airdale]

,,, the problem was caused by loading the approach without activating it ,,, So for that reason I think there are lots worse things than flying the magenta line ,,,

Yes. Except for trivial go-tos, my practice is to check the map after I have loaded a flight plan and after I've activated an approach -- to make sure I have what I expect. I guess that is sort of a situational awareness thing.

I would expect that the next waypoint on the approach would not be displayed, although I didn't notice whether this was the case during the flight.

I don't think it would have been and I also think that the little triangle on the CDI would have been "From" --- pointing back to DOCAL with the distance number counting up. Maybe one of the GPS gurus here can correct me if I am wrong. I am not where I can check it on the simulator right now.

 

[MikePapa]

After I got home, I looked through the manual to find out what would be the indications on the GPS screen of an approach not having been activated. This was a subject of vital interest to me, since in IMC I would not have the advantage of being able to see the hillside in front of me.

There's no requirement to activate the approach and in some cases doing so will get you in trouble if you are not certain where you are going. Once the approach is loaded you can select any fix on the approach, select direct-to, and away you go. Once you get on the approach everything will sequence as it should and you can legally fly the whole approach without "activating" anything. The only real advantage to activating an approach is it saves a very small amount of time spent on keystrokes so long as whatever you're activating is where you want to go. If ATC directs you to something other than a IAF or a FAF, activating the approach will actually take more time because you're then going to have to do a direct-to anyway.

Personally I very rarely, if ever, activate the approach because I always want to be sure where I am going. It's worth the extra keystroke or two to me to double check what fix I am navigating towards. That's where people get into trouble with the magenta line. They might know where they are, but they don't know where they are going, which is equally as important.

 

[olasek]

I absolutely confirm no need to activate approach. I once attended Max Trescott's (the one who wrote the G1000 book) seminar on G1000 and it was one of the points he stressed - there is no need to activate approach. Since then I purchased the G1000 PC trainer and already flew quite a few approaches (on my PC) and indeed - you don't need to activate anything. I can only assume that the logic in 430 is very similar.

the course line ahead of me was white after passing DOCAL on the first attempt,

I can only guess you inadvertently pressed the OBS mode because this would exactly be the case - the line in front of you would remain white. But since you were flying with 430 I can't be 100% sure, I can only offer plausible explanation based on G1000's behavior.

 

[airdale]

I can only assume that the logic in 430 is very similar.

Yes. G430/530/G1000 are virtually identical in the way the navigation is handled.

There's no requirement to activate the approach

Interesting. I never thought of that. So now, mulling it over: It makes great sense to me unless I am in a VTF situation. In that case it seems to me that I would want to activate VTF so that I can see (on the map or the CDI) the final approach course to make the intercept. Going Direct-To the FAF would not give me the course that ATC expects me to fly. And when I am released to intercept I am outside the approach gate, maybe 5 miles from the FAF, so the difference in courses may be significant. Or am I missing something?

 

[olasek]

Yes. G430/530/G1000 are virtually identical in the way the navigation is handled.
Going Direct-To the FAF would not give me the course that ATC expects me to fly. And when I am released to intercept I am outside the approach gate, maybe 5 miles from the FAF, so the difference in courses may be significant. Or am I missing something?

Not sure if this is what you have in mind but vectors to final are meant to be intercepted outside of FAF. For example if you are overflying the airport, coming from the opposite direction the GPS-WAAS will be put into SUSP mode until you get on the outside of FAF and then turn around to intercept the VTF magenta line. Actually this is one of the 'gotchas' Max explains in his book. If you prematurely try to 'unsuspend' - you will get into trouble, this may even cancel your approach. I am not sure if any harm can arise from going directly FAF if you remain on the correct side of it.

 

[MikePapa]

Interesting. I never thought of that. So now, mulling it over: It makes great sense to me unless I am in a VTF situation. In that case it seems to me that I would want to activate VTF so that I can see (on the map or the CDI) the final approach course to make the intercept. Going Direct-To the FAF would not give me the course that ATC expects me to fly. And when I am released to intercept I am outside the approach gate, maybe 5 miles from the FAF, so the difference in courses may be significant. Or am I missing something?

If you activate VTF, you will not see the final approach course on the map outside of the FAF. For this reason, many people do not ever activate VTF and instead chose an IAF or an IF that lines up on the approach course. The only problem with this method is that there isn't always another fix on the approach that lines up with the final approach course.

There is a way around that problem, at least on the G1000. I assume the 430/530s will do the same thing, but I have no experience with them. On the G1000, when you select direct-to the FAF, you then have the option of entering a course to that fix. If you select the final approach course, it will extend the line past the FAF and you get both course guidance on the HSI and an indication on the map, regardless of where the other fixes are. It takes a bit of time to do this, since you have to manually enter the course, but generally you know you're going to get vectors to final well in advance.

 

[Palmpilot]

I can only guess you inadvertently pressed the OBS mode because this would exactly be the case - the line in front of you would remain white. But since you were flying with 430 I can't be 100% sure, I can only offer plausible explanation based on G1000's behavior.

I just looked at the locations of the buttons, and what you're suggesting is quite possible. I do remember hitting the button to the left of the MSG button when I wanted the latter at one point, so that must have been it. Activating the approach cleared the problem, but it sounds like I was mistaken in assuming that lack of activating it was the original cause.

In any case, I'm glad to have learned that not having a magenta line ahead of me is a red flag.

 

[Henning]

I'm not talking airliner here. I'm talking Cessna 182.

Last weekend I heard a guy callup Chicago Center and Loc'd himself 15 E of the Joliet VOR. He was 15 West in another sector. The guy cannot work a Vertical omnirange.

No wonder controllers regard fliv operators as "OMG" cases.

So when you get an intermittent electrical bus short, and the I-nav hits the bunker, and there are no "landmarks" for a couple three thousand miles in each direction.....your fall back is not a VOR.

GA pilots as a whole need to have the ability to work a backup navigation routine. Occasionally the magenta line wil GO AWAY. So I am increasingly concerned these last ten years that the typical Joe Pilot has NO backup routine when the magenta goes away. We see the results with some frequency- the guy has typed in the wrong identifier....

Well, I've only been flying for 20 years, but I don't see where the situation has changed one iota in that time. People didn't know where they were back then either.

 

[Everskyward]

Well, I've only been flying for 20 years, but I don't see where the situation has changed one iota in that time. People didn't know where they were back then either.

I agree with you there. Technology has changed. The bell curve, not so much so.

 

[bbchien]

I agree the bell curve is still there. What we hve done is built a better tractor. Now we just do the back 40 which we never could do before.

So, the bell has shifted a bit- and includes some who are even dumber than 20 years ago.

Sigh.

 

[flyingcheesehead]

I just looked at the locations of the buttons, and what you're suggesting is quite possible. I do remember hitting the button to the left of the MSG button when I wanted the latter at one point, so that must have been it. Activating the approach cleared the problem, but it sounds like I was mistaken in assuming that lack of activating it was the original cause.

In any case, I'm glad to have learned that not having a magenta line ahead of me is a red flag.

So what you're saying is that if you had been in the habit of following a magenta line, you would have been fine.

 

[airdale]

If you activate VTF, you will not see the final approach course on the map outside of the FAF. For this reason, many people do not ever activate VTF and instead chose an IAF or an IF that lines up on the approach course.

Well, you may not see the extended final approach course when VTF is activated, but I always do. From the Garmin manual: "The ‘vectors’ option extends the final inbound course beyond the final approach fix, allowing the pilot to intercept the final course segment beyond its normal limits."

Maybe your sim is broken.

... I am not sure if any harm can arise from going directly FAF if you remain on the correct side of it.

If you're "not sure" whether any harm can come from not doing what ATC tells you to do, you need more help than you can get here.

 

[gismo]

There's no requirement to activate the approach and in some cases doing so will get you in trouble if you are not certain where you are going. Once the approach is loaded you can select any fix on the approach, select direct-to, and away you go. Once you get on the approach everything will sequence as it should and you can legally fly the whole approach without "activating" anything. The only real advantage to activating an approach is it saves a very small amount of time spent on keystrokes so long as whatever you're activating is where you want to go. If ATC directs you to something other than a IAF or a FAF, activating the approach will actually take more time because you're then going to have to do a direct-to anyway.

Personally I very rarely, if ever, activate the approach because I always want to be sure where I am going. It's worth the extra keystroke or two to me to double check what fix I am navigating towards. That's where people get into trouble with the magenta line. They might know where they are, but they don't know where they are going, which is equally as important.

I must admit I'm confused by this. While I'm not a frequent user of the 430W I do have some experience with them (and the simulator) and I was under the impression that until you activate the approach the GPS will not engage approach mode scaling of the CDI or validate the HPL/VPL for the approach, nor will the GPS provide guidance beyond the lines drawn on the map. What am I missing here? Are we talking about flying a GPS approach or just providing "situational awareness" on some other type of approach?

 

[gismo]

Well, you may not see the extended final approach course when VTF is activated, but I always do. From the Garmin manual: "The ‘vectors’ option extends the final inbound course beyond the final approach fix, allowing the pilot to intercept the final course segment beyond its normal limits."

Maybe your sim is broken.

If you're "not sure" whether any harm can come from not doing what ATC tells you to do, you need more help than you can get here.

I believe that the FAC only shows up if you are reasonably close to it (e.g. within 30 nm) but the depicted course line does extend well beyond the FAF and it should as it's never expected that you would be vectored to the FAC inside the FAF.

 

[MikePapa]

Well, you may not see the extended final approach course when VTF is activated, but I always do. From the Garmin manual: "The ‘vectors’ option extends the final inbound course beyond the final approach fix, allowing the pilot to intercept the final course segment beyond its normal limits."

Maybe your sim is broken.

I have no idea what sim you're using, but behind an actual G1000 if you activate vectors-to-final all your inbound fixes and legs disappear from the moving map except for the leg from the FAF to the MAP and the missed approach. The HSI works as you described, but depending on where you are and what range you have selected on the MFD, you may not even see the final approach course.

 

[twdeckard]

I was under the impression that until you activate the approach the GPS will not engage approach mode scaling of the CDI or validate the HPL/VPL for the approach

I believe the 430 will switch from terminal to approach mode within 2.0 of the FAF (and CDI scaling goes to .3) even if the approach is just loaded.

Let me fire up my simulator and play with it a bit.