When taking an ADF bearing close to the coast, when is coastal error minimized?

The correct response highlights that coastal error is minimized when the bearing from the ADF crosses the coast at a right angle, or 90 degrees. This is crucial for accurate navigation because the ADF (Automatic Direction Finder) is susceptible to various types of interference, one of which is the distortion caused by landmass proximity.

When the ADF bearing is perpendicular to the coastline, it reduces the effect of land-based reflections that can lead to erroneous readings. The signals received are less likely to be reflected away from the true bearing, thus providing a more reliable location reference.

In contrast, when a bearing approaches the coast at any angle other than 90 degrees, there’s a higher risk of distortion from both the coastal landmass and various radio signal reflections that can mislead the navigator about their true position. This is especially pertinent when navigating close to features such as cliffs or large coastal structures.

The other options, while they may have some relevance to navigation practices, do not specifically address the issue of minimizing coastal error in relation to ADF use.