Final answer:
Pilots must report specific situations to Air Traffic Control (ATC) without request, such as unforecast weather, safety issues, inability to meet flight parameters, missed approaches, and deviations from clearances for airspace safety and operational efficiency.
Step-by-step explanation:
The question relates to aviation regulations regarding communication between pilots and Air Traffic Control (ATC). There are certain reports that a pilot must make to ATC without being specifically requested to do so. These mandatory reports include, but are not limited to, unforecast weather conditions or weather changes, any safety-related issues or emergency situations, inability to climb or descend at a rate of at least 500 feet per minute, missed approach, leaving a holding fix or point, and any deviation from an air traffic control clearance.
When encountering these scenarios, it is crucial for the safety of the aircraft and the efficiency of the airspace system that a pilot proactively communicates the situation to ATC, so they can respond accordingly and provide necessary assistance or directions. While in controlled airspace, maintaining clear and continuous communication with ATC is a vital component of flight operations.