What phrase is used to inform a pilot that they are no longer under ATC control?

• A. "Go around."
• B. "Contact approach."
• C. "Frequency change approved."
• D. "Resume own navigation."

Answer: (C)

The phrase "Frequency change approved" is used to inform a pilot that they are no longer under ATC control. This phrase indicates that the pilot has permission to switch to a different frequency, typically to communicate with another facility or to operate independently.

When ATC uses this phrase, it implies that the pilot can now proceed on their own, managing their navigation and operations without further direction from the controlling ATC. This transition is crucial for the pilots to understand that they have entered an area where they will not receive further instructions from the tower or approach control. It helps facilitate a smooth handoff of responsibilities and ensures pilots are aware they need to follow their flight plans or procedures independently.

In contrast, other phrases like "Go around" and "Contact approach" involve active instructions from ATC to the pilot, while "Resume own navigation" suggests a different context where ATC might still maintain some level of oversight or guidance prior to fully handing off control.