On an approach chart, how can you differentiate between LOC/LDA Course and SDF Course?

The distinction between the LOC/LDA Course and the SDF Course on an approach chart primarily concerns the shading and presentation of the course lines. A LOC (Localizer) or LDA (Localizer Type Directional Aid) Course is typically represented with a half-shaded line on the chart, while the SDF (Simplified Directional Facility) Course is shown without any shading. This visual difference is essential for pilots to quickly identify the type of course they are navigating, as it impacts how the aircraft is aligned for the approach.

The shading helps distinguish between the two types of navigation aids, aiding in situational awareness during an approach. An understanding of these markings is crucial for effective navigation and ensuring compliance with approach procedures. Thus, being able to recognize a LOC/LDA by its half-shaded representation versus the SDF which has no shading is key to correctly interpreting the charts.

While other choices may mention additional features or symbols, they do not accurately depict the simplest and most visual differentiation between these course types as indicated by the shading.