Which phraseology is used to obtain altitude reports from an aircraft?

The phraseology "report leaving odd altitudes" is commonly used in air traffic control communications to require pilots to provide updates on their altitude changes when transitioning through specific altitude levels, particularly when flying at odd altitudes. This is especially important in airspace where altitude assignments are critical for maintaining safe separation between aircraft.

The purpose of this communication is to ensure that controllers can maintain an accurate picture of the airspace and manage aircraft efficiently. It prompts pilots to report when they depart from an altitude that is classified as "odd," which typically consists of altitude levels that end in 1, 3, 5, 7, or 9. By having pilots report this information, controllers can verify that aircraft are adhering to their assigned altitudes, especially in environments where traffic may be dense and altitude separation is crucial for safety.

In contrast, the other options do not effectively serve the same function. For instance, asking pilots to report cruising altitude or current altitudes does not specifically focus on changes that might affect separation between aircraft. Additionally, requesting reports on leaving even altitudes may not align with standard operational protocols, which often emphasize odd altitude reports for specific traffic situations. Therefore, the wording of the correct choice directly addresses the need for situational awareness