What documentation is required for an aircraft flying into Mexico?

When flying an aircraft into Mexico, there are specific documentation requirements that must be met to ensure compliance with international aviation regulations. The correct answer identifies essential documents, which include an Instrument Flight Rules (IFR) flight plan, an Advance Passenger Information System (ADCUS) declaration, a radio operator certificate, and a valid passport for the pilot.

The IFR flight plan is necessary as it indicates the planned route and helps air traffic control manage safe navigation and operations in controlled airspace. The ADCUS declaration is important for customs and immigration, summarizing passenger and crew information for authorities. A radio operator certificate demonstrates that the pilot is qualified to use the aircraft's communication equipment, which is critical for safety and compliance during international operations. Lastly, a valid passport is required for identity verification and legal entry into the country.

This combination of documents ensures that not only are safety and operational requirements met but also that pilots and aircraft are compliant with the legal and regulatory standards set by Mexican authorities.