What effect does steering by magnetic compass have on lateral separation?

Steering by magnetic compass can lead to wider approaches compared to using a gyrocompass due to the inherent limitations and errors that come with magnetic guidance. A magnetic compass is subject to magnetic variation and deviation, which can cause fluctuations in course direction. These variations can lead to inaccuracies, especially in navigating tight turns or when approaching a specific destination.

As a result, operators often have to compensate for these inaccuracies by widening their approach paths to ensure safety and maintain sufficient lateral separation from other vessels or obstacles. This need for a wider approach allows navigators to account for any potential drift or errors the magnetic compass may introduce, ensuring a more cautious and secure navigation process.

In contrast, a gyrocompass, which is less affected by external magnetic influences and provides more stable and precise directional information, allows for narrower approaches. Therefore, using a magnetic compass necessitates wider approaches to maintain safety and accuracy in navigation.