Wind, Navigation, and You, Part 3

If you’re just joining us for this Pilot Knowledge series on The Training Aviator, you might want to read the first two parts of Wind, Navigation, and You before proceeding, unless your grasp of basic meteorology, airspeed definitions, and the wind triangle is strong. Again, no harm no foul if you refer back to those articles in any event.

Using the E6-B Flight Computer

The E6-B is a mechanical analog computer designed specifically for aviation navigation problems. It allows you to solve the wind triangle quickly and accurately.

To use it for wind correction, flip it over to the “wind side.” You set the wind direction under the true index, mark the wind speed, rotate the device to your true course, and then align your true airspeed. The device will provide both the wind correction angle and groundspeed. The process reinforces the geometry of the wind triangle and builds intuition. The FAA highlights the continued relevance of these manual tools even in the age of electronic computation (Weight and Balance Handbook Chapter 10, p. 10-2).

Electronic Flight Computers and Applications

Modern pilots often rely on electronic flight computers, apps, and avionics systems to compute wind correction angles automatically. These tools integrate GPS data, winds aloft forecasts, and aircraft performance to provide real-time solutions.

However, reliance without understanding is risky. If the system fails or inputs are incorrect, the pilot must still be able to recognize and correct errors. This aligns with the FAA’s emphasis on risk management and situational awareness (Risk Management Handbook Chapter 1, p. 1-1).

Understanding the underlying math allows you to verify results and maintain control over navigation.

True North, Magnetic North, and Variation

All the calculations you’ve done have been regarding true north, but the compass in your airplane is aligned with magnetic north. How do we convert from true to magnetic?

True north is the geographic North Pole. The local horizontal component to the earth’s magnetic field is what a compass aligns with. These two are not the same, and the difference between them is called magnetic variation.

In Fig. 6, we can see the location of the North Pole (marked “TN”) and the Magnetic North Pole (marked “MN”). The curved red lines emanating from the Magnetic North Pole are magnetic meridians. Lines that connect places having the same magnetic variation are called isogonic lines, and are printed on VFR sectional charts. Each line is depicted as a magenta dashed line with a magnetic variation (9° west, in this case) printed periodically along the line.

To convert between true and magnetic directions, pilots use the rule: “East is least, west is best.” In other words, subtract easterly variation and add westerly variation when converting from true to magnetic.

• If you wanted to fly due west (true) over Ashtabula, you would need a magnetic heading of 279° (270° + 9° = 279°).

• If you were flying over Ashtabula on a 144° magnetic heading, you could find your true heading by subtracting 9 from 144 (144° – 9° = 135°).

We use true directions as a starting point in flight planning because variation changes geographically. If we tried to navigate using only magnetic values, the math would become significantly more complex as we moved across regions. Likewise, because winds aloft are forecast over a wide area, they are reported as “true.” The PHAK discusses this in detail (Chapter 16, p. 16-6).

As a final step, we then apply compass deviation in order to get to the course to fly.

Final Thoughts

Wind correction angles are not just a theoretical concept—they are a practical necessity. Every cross-country flight requires you to account for wind to maintain an accurate ground track and predictable arrival time.

By understanding how wind affects your aircraft, how headings differ from courses, and how airspeed differs from groundspeed, you gain the ability to navigate with precision. Whether you use manual tools like the E6-B or modern electronic systems, the principles remain the same.

Master the fundamentals, and the tools become enhancements rather than crutches.