What documents must a flight instructor have while operating an aircraft?

In order to operate an aircraft as a flight instructor, it is essential to possess both an appropriate pilot certificate and a flight instructor certificate. The pilot certificate ensures that the instructor has met all necessary training and experience requirements for the type of aircraft being operated, while the flight instructor certificate specifically authorizes the holder to instruct other pilots. This combination not only confirms the instructor’s qualifications but also ensures compliance with aviation regulations that mandate the necessary credentials for instructional flight operations.

The other options, while related to aviation qualifications, do not fully encompass the specific requirements for flight instructors. Having a current pilot certificate and a medical certificate is important for all pilots, but it does not include the necessary specifics of the flight instructor role. A pilot logbook with endorsements is important for tracking flight experience and verifying qualifications; however, it is not a regulatory document required for operation of the aircraft. Personal identification and a medical certificate are also important but do not provide the specific authorization to instruct and operate as a flight instructor. Hence, the correct response emphasizes the crucial combination of both an appropriate pilot certificate and a flight instructor certificate.