Airspace & Navigation - Tracking a VOR | Training Blog

How do you avoid reverse sensing when tracking a VOR? How do you correct for wind drift?

AI-generated editorial illustration of VOR tracking over Eastern Iowa. The shaded panel, illuminated CDI, blue course lines, and GCAC wings emphasize the training concept; the image is not a navigation chart or a depiction of an actual flight.

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Keep the Course and Indication Together
A VOR station defines 360 magnetic lines called radials, and every radial extends from the station. The 180° radial, for example, extends south. If you are on that radial and want to fly north to the station, your inbound course is the reciprocal, 360°. For the outbound trip south, your course is 180°.
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The omnibearing selector (“OBS Knob”) sets the course you want to fly. The course deviation indicator, or CDI, shows whether that selected course lies left or right of the airplane, while the TO/FROM indication identifies the course's relationship to the station. A centered needle alone does not prove that the receiver is set correctly; the CDI can center on either direction of the same course line.

Despite their seeming complexity, CDIs are simple - select the course you intend to fly, then confirm TO for an inbound course or FROM for an outbound course. In the example, set 360° and confirm TO when flying north to the station; set 180° and confirm FROM when flying south away from it. If the course is set for the opposite direction, the CDI will command corrections in the wrong direction.
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Tip: Keep the head of the selected VOR course and the airplane's nose generally pointed in the same direction, then verify the TO/FROM indication before trusting the needle.
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For wind drift, use the needle as course information rather than a steering command. If it moves off center, turn toward the selected course with a modest intercept angle. As the needle returns, reduce the intercept and establish a small wind-correction angle into the wind. Adjust that crab a little at a time. Chasing every needle movement tends to produce overshoots and S-turns instead of a stable track.

The FAA example shows the airplane drifting left of course, intercepting back toward the course, and then holding a smaller wind-correction angle. Source: FAA Pilot's Handbook of Aeronautical Knowledge, Chapter 16, Figure 16-32, p. 16-25.

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Apply It Near Green Castle
The current Chicago Sectional provides a useful local picture. Green Castle Airport (IA24) lies southeast of the Cedar Rapids VOR/DME (CID), close to the facility's 156° radial. A pilot using that line toward CID would select the reciprocal course, approximately 336°, and confirm TO. Flying southeast away from CID would call for approximately 156° with FROM.

The FAA Chicago Sectional shows IA24 near the CID 156° radial, making the reciprocal inbound course about 336°. This excerpt is for instruction; use a current chart and verify the facility before flight.

This local example connects three ideas that are easy to blur together: a radial names the line from the station, a course names the direction you intend to fly along that line, and heading is where the nose points. The related GCAC refreshers on VOR, DME, TACAN, and VORTAC and course, heading, and track explain those building blocks.
Before trying it in the airplane, use the VOR Trainer on GCAC's E-Teaching Tools page. Change the selected course and aircraft heading, then predict the CDI and TO/FROM indications before looking at the result. In flight, identify the station, verify a usable signal, and make smooth corrections. Near station passage, allow for rapid or unreliable indication changes rather than chasing the needle.

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FAA Sources and References
Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25C, Chapter 16, pp. 16-24 to 16-26 and Figure 16-32
Aeronautical Information Manual, Chapter 1, Section 1, paragraph 1-1-3
FAA VFR Raster Charts, Chicago Sectional chart

Next Week
Regulations - Airworthiness Directives
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What are airworthiness directives (ADs), and when are they issued?

A maintenance record can look complete and still leave an essential compliance question unanswered. Next week, we'll examine why the FAA issues airworthiness directives and what a pilot should confirm before flight.