Which component of flight navigation helps identify checkpoints during the flight?

The correct choice is the data box. In the context of flight navigation, the data box serves as a critical tool for pilots to keep track of their current position, upcoming waypoints, and various flight parameters. It typically displays dynamic information such as headings, distances to the next waypoint, altitude, and time estimates, which are essential for maintaining situational awareness during the flight. By continuously updating this information, pilots can easily identify checkpoints along their route, ensuring they stay on track and make timely adjustments as necessary.

While the flight plan outlines the intended route and includes checkpoints, it does not actively provide real-time data during the flight. The flight log records the actual progress, but it is more about documenting the journey rather than facilitating navigation in real time. Navigation charts provide essential geographical information and help with reference points, but they do not specifically highlight checkpoints dynamically as the data box does.