Final answer:
Pilots must "cancel IFR" at an uncontrolled airport to switch to VFR operations and update ATC. This cancellation is important for air traffic flow and safety.
Step-by-step explanation:
When an aircraft is operating under Instrument Flight Rules (IFR) and wishes to transition to Visual Flight Rules (VFR) while approaching an uncontrolled airport, the pilot must "cancel IFR" to inform Air Traffic Control (ATC) that they will no longer require the IFR services and are now operating under VFR. This cancellation is necessary so that ATC can update their traffic management system and advise other traffic accordingly. It's critical for maintaining proper air traffic flow and ensuring safety. At uncontrolled airports, which do not have an operating control tower, pilots are responsible for the see-and-avoid principle and for announcing their intentions on the common traffic advisory frequency (CTAF) so that other pilots in the vicinity are aware of their presence and intentions.