Relative Bearing

What is Relative Bearing?

Relative bearing is the angle between the aircraft's longitudinal axis (the direction the nose is pointing) and the direction to an object or station, measured clockwise from the nose. It ranges from 0° (dead ahead) through 360°.

Relative Bearing Calculation

To find the true or magnetic bearing to a station, add the aircraft's heading (true or magnetic, as required) to the relative bearing:

• True Heading + Relative Bearing = True Bearing to the station (QUJ)
• Magnetic Heading + Relative Bearing = Magnetic Bearing to the station (QDM) If the sum exceeds 360°, subtract 360° to keep the result within the 0–360° range.

ADF and Relative Bearing in Aviation

When using an Automatic Direction Finder (ADF) with a Non-Directional Beacon (NDB), the instrument displays the relative bearing to the station. Pilots must add their current heading to the indicated relative bearing to determine the actual bearing to the NDB. This is crucial for accurate navigation, especially when plotting positions or intercepting bearings.

Relative Bearing vs Magnetic Bearing

• Relative Bearing: Measured from the aircraft's nose.
• Magnetic Bearing: Measured from magnetic north. Converting between them requires knowing the aircraft's heading and applying the correct calculation.

Common Causes and Symptoms of Relative Bearing Errors

Errors can occur if the pilot misreads the instrument, uses the wrong heading (true vs magnetic), or forgets to adjust for values over 360°. These mistakes can lead to incorrect plotting, loss of situational awareness, and navigation errors.