Tips for VOR/LOC position questions on IR exam?

MuseChaser

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MuseChaser
I'm working through a course to prep me for taking the IR exam, and it's all going great.. pretty much ready..but the questions where they give you a couple CDI readings, frequencies, then a chart and ask you to describe where you are in relationship to a fix bug me. Not because I can't do them.. I get them right every time.. but because it takes me SO long to figure each question out. In an airplane, it'd be worthless because by the time I figured it out, I'd be a mile or two away from there.

To be clear, I understand how they work, and have been using VORs for navigation for years as a VFR-only pilot. There's just something about the difference between being given the readings and data first, rather than deciding to track a certain VOR, putting in the frequency, and tracking the radial that slows things down for me. I know the heading of the plane has nothing to do with it's location relative to a VOR, LOC, or fix, that the backcourse of a LOC is reverse-sensing, to check the TO-FROM indicator on the CDI... the basics I get. I'm just so slow at it.. and I'm not usually a slow guy. Any tips from any of you... or is it just a matter of keeping at it until my pea-brain can process the info faster?
 
Had to dig this out of the mothballs because VOR's messed with me too on my instrument training.

For me, I like to visualize the to/from indicator as a cone and I use the top of the VOR as outbound headings, bottom of the VOR are inbound headings. The opening of the cone shows me where I am.

If I was to fly 210 so my DG matched what my VOR is showing, I would be 030 inbound to the station (opening of the cone pointing to 030 and 030 at the bottom of the VOR). If I rotated the OBS to have the 030 at the top, and turned the plane so that it matched the VOR I would be on the 030 outbound (030 top = outbound, flip flop would also show the opening of the cone pointed that way too)

With practice you can with accuracy of about 80 degrees tell exactly where you are in relation to a VOR without ever turning the OBS knob. Even with a full deflection of the needle.
 
Don’t let this worry you.

In the air you have had time to arrive at this point in space. Your situational awareness has been working for the last XX minutes leading up to now.

On the exam you’re being given this information cold, and being asked where you are. It takes time to digest.

Get through the exam. Sounds as if you’re doing great!
 
Sympathies! I hated this part of the IR exam as well, and yes, it took me time to complete the problems. Stick with it, and you'll get it done.
 
The point of these questions is to see if you actually understand how the indicators work and what they mean. Because there is no pretextual context, it will take longer to figure out than if you were monitoring your actual position continuously. So don't worry as long as you can figure it out.

The real fun will be figuring out your hold entry without using the magic box. If you can do that in flight--and you do get quite a few minutes to figure it out--you have sufficiently good spatial comprehension skills. :cool:

Flying the 430W is almost like "cheating." But I don't miss the old ways that much, other then to stay proficient enough to do it in an emergency.
 
Memorize the following drawing and regurgitate it on scratch paper (or even better, on one of the transparencies) during the test. It depicts a VOR station in the center of the cross with the appropriate CDI picture in each quadrant. Turn the drawing so it points in the direction of the OBS (e.g., upside down if the OBS is set to 180°). Match the CDI(s) given on the test to the one on the drawing to determine which corresponds to which aircraft location.
Screen Shot 2019-09-25 at 4.40.49 PM.png
 
You guys are the greatest...thanks. The tips help a bunch, but knowing I'm not the only one who doesn't enjoy those questions helps at least as much!
 
I'll add another quick one. You can answer a surprising number of the HSI questions by eliminating the choices where the heading of the airplane doesn't match the HSI heading. You'd think the FAA would make it more difficult, but many times all 3 choices have different headings.

Otherwise, an HSI is just a CDI superimposed on a heading indicator which rotates with the heading. You can unrotate it in your mind and use the same technique (whichever that technique happens to be) to answer HSI questions as you do for CDI questions.
 
I'm working through a course to prep me for taking the IR exam, and it's all going great.. pretty much ready..but the questions where they give you a couple CDI readings, frequencies, then a chart and ask you to describe where you are in relationship to a fix bug me. Not because I can't do them.. I get them right every time.. but because it takes me SO long to figure each question out. In an airplane, it'd be worthless because by the time I figured it out, I'd be a mile or two away from there.

To be clear, I understand how they work, and have been using VORs for navigation for years as a VFR-only pilot. There's just something about the difference between being given the readings and data first, rather than deciding to track a certain VOR, putting in the frequency, and tracking the radial that slows things down for me. I know the heading of the plane has nothing to do with it's location relative to a VOR, LOC, or fix, that the backcourse of a LOC is reverse-sensing, to check the TO-FROM indicator on the CDI... the basics I get. I'm just so slow at it.. and I'm not usually a slow guy. Any tips from any of you... or is it just a matter of keeping at it until my pea-brain can process the info faster?

This is a different (easier) way to visualize the CDI: http://sarangan.org/aviation/2003/10/26/vor-as-a-course-instrument/

But it is hardly relevant today with GPS navigation.
 
This is a different (easier) way to visualize the CDI: http://sarangan.org/aviation/2003/10/26/vor-as-a-course-instrument/

But it is hardly relevant today with GPS navigation.

Very interesting article.. thanks! Gotta admit I had to stare and think about the last example (finding the headings to fly towards an intersection of two radials) for a while before I could come to grips as to why it doesn't matter which way the TO/FROM indicators where pointing, and still took me forever to figure out, from those readings, where exactly the airplane WAS in relation to the intersection. I think the part I was missing, and this may seem obvious, is that when the radial is at the top (or bottom) of the OBS selector, the centerline of the OBS IS the radial on the diagram, and the airplane is on the opposite side of that radial from the needle deflection. Using that, it was a lot easier to place the airplane in relationship to the two radials, even though it's still impossible to pinpoint its exact location. Hopefully, I've got this right.. I've attached a snip with where I think the airplane is...

As far as making real-world faster selections of appropriate courses to fly in order to intercept a radial... very cool! Much easier and faster.VOREx.JPG
 
Practice practice practice. If you are getting them all right who cares how long it takes you.
 
You are figuring it out. That's all that matters. I knew a pilot who thought if the VOR needle was to the left it meant to turn left, and turn, and turn, and turn. He couldn't figure out that he would never get to the centerline of the track if he was more than one turning radius away from it. Would just keep flying circles. No clue...flying XC with this pilot was an exasperating experience.
 
I knew a pilot who thought if the VOR needle was to the left it meant to turn left, and turn, and turn, and turn.
I had to pink slip a mathematician who did that on a private flight test. He was not happy with me for bruising his ego and never returned.
 
I get them right every time.. but because it takes me SO long to figure each question out.
I'm not too interested in slick tricks you might forget by the time you need them. Solving puzzles isn't a speed test it's a test of your methodology. If you simply place your back to the station (at the center of the dial facing up) with a "From" or face the station (looking inward from the edge of the dial also facing up) with a "To" I think you'll deduce the answer fast enough. Remember, the written questions make you figure out four answers before you can can select the best one, so it takes you four times as long as it would in flight.
 
Don’t let this worry you.

In the air you have had time to arrive at this point in space. Your situational awareness has been working for the last XX minutes leading up to now.

On the exam you’re being given this information cold, and being asked where you are. It takes time to digest.

Get through the exam. Sounds as if you’re doing great!

Here is your answer. Those stupid VOR and HSI questions take a long time because it's like you're getting dropped somewhere on the planet and now you have to figure out where you are (which will never happen). Just struggle through them and move on.
 
The vor questions take me 2 seconds in the plane and 5 minutes on the test.
That's why I hated those questions. Apparently the FAA doesn't realize that an indicator comes with a knob you can spin, to center the VOR. I get that with these questions they are testing that you understand the concept of how a VOR works, I just question that THEY (the FAA) understand the usage.
 
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Forget about "reverse sensing" on the localizer. It's immaterial to the questions on the exam and even in real life screws people up. Reverse sensing has nothing to do with the "back course." The back course Left/Right indication is the same as the front course. The only thing "reverse" that happens is if you are flying in the opposite direction as the localizer is designated (whether you are on the front or back course). Because you're turned 180 degrees your understanding of left/right is backwards.

The only LOC question if I recall correctly uses HSIs. It's this one where there is a picture of an ILS and BC on a runway with about 13 arrows in various orientations. First thing is to eliminate all the ones that are the wrong heading based on the HSI. Then look at the ones remaining and then the needle will be the runway and the center of the HSI will be the plane after you turn the picture so it is oriented the same way as the aircraft arrow.
 
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