Flying the Magenta Line

In the 737's I have been in. I have never seen them switch a page to an HSI type of display.

I took this on a jumpseat from BUR to OAK

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That is the typical setup I have seen SWA pilots do. What you can't see is both the the far left and the far right displays. That is set up as a typical PFD would be. I am sure they can switch to an HSI display but I have not seen it. I am not meaning to get in a ****ing contest, just to show that some modern flight decks in aircraft, can be flown without an HSI. No matter what, you are either trying center a needle, center a triangle, or deviation indicator to a reference line.
 
Inverted said:
What I was meaning, was that a full glass avionics suite might not have a typical HSI.
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Here's ours.

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Inverted said:
as you can see, even on that HSI, it is flying an airplane on a magenta line
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Sure the needles are magenta and we are flying off the FMS data, but when I think of flying the magenta line I think using the MFD to steer, which I don't do.

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Unfortunately I don't have a picture of the MFD in flight.
 
Inverted said:
In the 737's I have been in. I have never seen them switch a page to an HSI type of display.

I took this on a jumpseat from BUR to OAK

2f0d7ph.jpg


That is the typical setup I have seen SWA pilots do. What you can't see is both the the far left and the far right displays. That is set up as a typical PFD would be. I am sure they can switch to an HSI display but I have not seen it. I am not meaning to get in a ****ing contest, just to show that some modern flight decks in aircraft, can be flown without an HSI. No matter what, you are either trying center a needle, center a triangle, or deviation indicator to a reference line.
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Yes, you can change the navigation display to a traditionl HSI type, but most don't bother because while you can't see it in that photo, the CDI 'Needles' (and G/S) are actually built into the attitude display on the left side of the moving map display.
 
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I have observed those types of displays and they indeed have an HSI on the main setup. The difference is that it is on the bottom of the screen and on an horizontal mode. The garmin perspective can display it the same way.
 
Everskyward said:
I fly with a glass cockpit and set the display to HSI. So do the other people I fly with. Even if you set the display to ARC you still get the top half of the needles.
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Huh? An Aspen Evolution display (well, its bottom half) looks a whole lot like an HSI.
 
I doubt avionics could be certified for IFR without some sort of needle display, HSI, ARC mode, or CDI. How else would you steer if the autopilot was inop? Oh that's right, you would fly the magenta line on the MFD. :goofy:
 
If you zoom in enough, the magenta line on the map screen is way more precise than either the onscreen CDI or the physical CDI. That's how I was able to hold cross-track error to under 10 meters over a 50 mile course when flight testing some radio equipment for work.
 
airdale said:
I just read a couple of posts this morning talking about flying the magenta line or the equivalent, flying the little airplane around a georeferenced plate.

I have always considered this to be a sign of sloppy piloting. First, the accuracy of flying the magenta line depends on the scale setting of the moving map display. This means you can be far off course and looking good. Second, it creates reliance on a single gadget and over time IMHO weakens the pilot's ability to use the rest of the panel to navigate.
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In IFR operations, how do you know the pilots involved aren't including the CDI in their scan?

In VFR operations, I'm more concerned that my bearing not wander too much, so that I am not unnecessarily adding to the length of the trip. A moving map set to track up indicates that very effectively, regardless of the scale setting. If there is some airspace that I need to avoid, I zoom in as needed if my route takes me close enough for it to be an issue.
 
airdale said:
When flying as safety pilot I frequently see people flying holds using the moving map.
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Why is that a problem? I imagine that would improve the precision of flying the hold for many pilots, me included (although I would adjust the leg length to get the desired timing). And of course the CDI is available at a glance. (Or is that not the case with glass panels?)

What stimulated my question was a mention here (another forum) by a student pilot of "flying the magenta line" on an approach.
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Are you talking about an instrument approach? If so, they definitely need to be including the CDI in their scan. If you mean a VFR student pilot making a VFR approach, they obviously need to know how to do it by looking out the window.
 
Everskyward said:
There is no source difference, but there is definitely a difference in technique based on whether someone is primarily looking at the needles as opposed to steering the airplane symbol.
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AS long as the GPS is in "track up." you can use the magenta line VERY much like an HSI. You do not steer with the airplane symbols whatsoever.

All that needs to happen is that the airplane symbol starts out on ML and then the pilot keeps the ML line ABSOLUTELY VERTICAL.
 
kgruber said:
All that needs to happen is that the airplane symbol starts out on ML and then the pilot keeps the ML line ABSOLUTELY VERTICAL.
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Interesting technique. I'm sure I've never heard anyone advocating using it.
 
I fly a Champ so I can't stray THAT far off the magenta line without having to stop for lunch.
 
kgruber said:
All that needs to happen is that the airplane symbol starts out on ML and then the pilot keeps the ML line ABSOLUTELY VERTICAL.
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Ever fly with a crosswind?
 
Wow, OP here. You leave a thread for a day and it becomes unrecognizable!

Just for the record, by "flying the magenta line" I meant using the moving map to determine whether one is on or off course and making correction accordingly. Hand flying, not looking at needles or pointers of any kind. Sorry that I was not clearer.

Re HSIs, arc HSIs, needle CDIs, and digital CDIs, those are what I think are the preferable tools for determining position and making corrections when flying a GPS course. The main reason is that their sensitivity doesn't change as the map scale changes. 5nm scale is as numb as they get. The second reason is that in some cases (ILS, airplanes with no GPS) they are the only tool, so it is better to be comfortable using them.
 
pericynthion said:
Track up.
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Having just flown 700-some-odd-miles yesterday with a serious crosswind, well, my point-of-view is more than slightly different.

My magenta lines are on the 430w and the Aspen. They are not equal.
 
Clark1961 said:
Having just flown 700-some-odd-miles yesterday with a serious crosswind, well, my point-of-view is more than slightly different.

My magenta lines are on the 430w and the Aspen. They are not equal.
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How are they "not equal?" Equal to what?
 
kgruber said:
How are they "not equal?" Equal to what?
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The magenta lines are not equal to each other in displaying the heading and track of the aircraft. Track is up on the 430 and heading is up on the Aspen.
 
Clark1961 said:
The magenta lines are not equal to each other in displaying the heading and track of the aircraft. Track is up on the 430 and heading is up on the Aspen.
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My method works on "Track up." As I indicated on my first post.

BTW, remember where you heard it first. APS teaches one of my methods that I posted on Avsig nearly 20 years ago. I have yet to be given any credit.
 
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kgruber said:
Never mind. my mistake.
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Sure. No big deal. It was sorta fun yesterday watching the displays and navigating by looking out the window. My "base" leg was more of a 45 to join final. :)
 
For IFR flight, doesn't the 430 and 530 require a connected CDI? The aircraft I have flown have the CDI connected to the Garmin with a switch to select either the GPS of the NAV.
In order to get my 89B ifr certified I have to add a CDI that tracks my desired path even though the 89B has a digital cdi as one of the screens.
 
Clark1961 said:
The magenta lines are not equal to each other in displaying the heading and track of the aircraft. Track is up on the 430 and heading is up on the Aspen.
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If there is no way to display track up on the Aspen, then you would have to use another method of compensating for crosswind.
 
Everskyward said:
Interesting technique. I'm sure I've never heard anyone advocating using it.
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I use that method as an efficient way of determining if my bearing is correct. I figure that it reduces the number of times I have to make a correction to recenter the CDI needle.
 
Palmpilot said:
If there is no way to display track up on the Aspen, then you would have to use another method of compensating for crosswind.
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Centering the bar on the e-HSI works just fine.
 
Clark1961 said:
Centering the bar on the e-HSI works just fine.
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Thanks. I thought I remembered something like that from my Aspen ground school, but I ended up not flying Aspen-equipped planes enough to remember what it was.
 
Palmpilot said:
I use that method as an efficient way of determining if my bearing is correct.
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Do you mean your heading?

Palmpilot said:
I figure that it reduces the number of times I have to make a correction to recenter the CDI needle.
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Is that something you were taught or something you came up with on your own? I always figured that the CDI needle was what you should be mainly using, and the moving map was just for general reference. I don't think it matters if you are VFR since you don't need moving maps or needles at all but it's interesting to me that people would even consider the moving map as the primary means of navigation when IFR.
 
kgruber said:
Ditto 430
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And you would fly an approach that way?

I am by no means 430/530 expert, but I suspect from a Human Factors standpoint, that an HSI type display is much easier to use when flying an approach.

Do you have a photo you can post of that display?
 
Fearless Tower said:
And you would fly an approach that way?

I am by no means 430/530 expert, but I suspect from a Human Factors standpoint, that an HSI type display is much easier to use when flying an approach.

Do you have a photo you can post of that display?
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For the approach, you don't use an HSI-like portrayal on the screen. You use the real life HSI in the 6-pack in front of you.
 
JHW said:
For the approach, you don't use an HSI-like portrayal on the screen. You use the real life HSI in the 6-pack in front of you.
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That is my point. You have a couple people here that somehow feel the moving map is far superior and HSI or CDI display is archaic, but they are really two independently different tools.
 
Everskyward said:
Yes. Personally I think it's much less accurate to "fly" the airplane symbol than to fly the needles.
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I've never seen a magenta line used without Current Track, Desired Track and Cross Track Error shown, which is far more accurate information than any CDI has ever delivered.
 
LDJones said:
I've never seen a magenta line used without Current Track, Desired Track and Cross Track Error shown, which is far more accurate information than any CDI has ever delivered.
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Would you fly an instrument approach only looking at that display rather than a CDI or HSI? If you had to choose one or the other, which would you choose?
 
Everskyward said:
Would you fly an instrument approach only looking at that display rather than a CDI or HSI? If you had to choose one or the other, which would you choose?
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After 35 years needles are pretty well engrained, but I've made approaches both ways for training purposes, and backed up VOR approaches with a Garmin 295 for over a decade and the magenta line coupled with the data fields was far more accurate than the needle.
 
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LDJones said:
After 35 years needles are pretty well engrained, but I've made approaches both ways for training purposes, and backed up VOR approaches with a Garmin 295 for over ask decade and the magenta line coupled with the data fields was far more accurate than the needle.
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If you have cross-track error as well as DTK and TRK, the ML can probably be more precise. But as I'm sure you know, there are often significant differences between the GPS-calculated course and the actual radial of a VOR approach, probably because of not taking into account station declination. The ML my 480 generates for the VOR 27 @ KFNT, for example, is about 5 degrees north of the real approach course. On my instrument checkride the DPE made sure I was using the CDI coupled to the NAV receiver.
 
LDJones said:
After 35 years needles are pretty well engrained, but I've made approaches both ways for training purposes, and backed up VOR approaches with a Garmin 295 for over ask decade and the magenta line coupled with the data fields was far more accurate than the needle.
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I also learned exclusively with needles. I've never tried just using just the magenta line. I find that I only glance at the moving map for a general reference but would never try to fly off of it. I'm not even sure what people are taught as far as using the moving map any more. It seems that some use it as their primary instrument for navigation which is the opposite of anything I ever learned.

If you were teaching a new instrument student, what technique would you tell them to use regarding the CDI/HSI vs. the moving map?
 
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