If taking a VFR flight of 123 nautical miles, what must the pilot-in-command ensure?

The pilot-in-command must ensure that the airworthiness certificate is legible because this document is crucial for confirming that the aircraft is in a condition for safe operation. An airworthiness certificate indicates that the aircraft meets safety standards and is compliant with regulations. This certificate also needs to be readily available for inspection by authorities and should be clear to ensure that all necessary information is visible.

While having sufficient fuel and excellent weather conditions are certainly important for a successful flight, they are not specific requirements that must be documented or verified like the airworthiness certificate. Similarly, while it is prudent to file a flight plan, it is not a requirement for Visual Flight Rules (VFR) flights under certain conditions, assuming the pilot meets all necessary regulations and safety standards. Thus, ensuring that the airworthiness certificate is legible is a fundamental responsibility of the pilot-in-command that directly affects the legality and safety of the flight.