What should you note on your route that can be used as a time check or as a position check?

The correct choice for identifying a reference that can be used as a time check or position check during a flight is landmarks. Landmarks are distinct geographic features such as mountains, rivers, or cities that are easily recognizable and can serve as visual references during navigation.

By observing these landmarks, pilots can confirm their position relative to their intended route and estimate their progress, which can be particularly helpful in visual flight rules (VFR) contexts. Recognizing specific landmarks also provides the opportunity to cross-check estimates of flight time by assessing how long it takes to reach these features along the planned route.

While waypoints are also significant in navigation, they typically represent specific points defined by coordinates in a navigation system rather than visual references. Altitudes are critical for maintaining safety and adherence to air traffic control requirements but do not serve as visual indicators for geographic checks. Flight paths pertain more to the planned trajectory and less to identifiable features in the environment. Hence, landmarks are the most effective for time and position checks during a flight.