Licensing and Aircraft Registration
This domain covers who may fly, who may certify, and how an aircraft acquires legal nationality. Understand the licensing structure: the private pilot licence as the baseline, the commercial and airline transport licences with their progressively higher experience and privilege thresholds, and the ratings (class, type, instrument, instructor) that extend privileges. Know the difference between privileges (what the holder may do) and requirements (what must be met to hold or exercise them), and be able to state the common validity and recency concepts: licence validity periods, medical certificate classes and their durations, and the fact that a rating's validity and a licence's validity are separate things.
For registration, know that an aircraft has the nationality of the state in which it is registered, must carry its nationality and registration marks, and that registration is recorded in a national register. Understand the certificate of registration and certificate of airworthiness as distinct documents: one establishes nationality, the other establishes airworthiness. Know the concept of transfer of registration between states and that an aircraft cannot be validly registered in two states at once.
Traps: questions conflating medical certificate validity with licence validity; assuming an airline transport licence automatically confers instructor privileges; and items that treat the certificate of airworthiness as proof of nationality. Watch for wording about "current" versus "valid" - recency requirements can lapse while the licence remains valid.
Rule of thumb: nationality comes from the register, airworthiness from the certificate of airworthiness, and permission to fly from the licence plus valid ratings and medical - four separate links in one chain.
Worked example: A pilot holds a valid licence but the class rating lapsed last month. The licence is still valid, but the pilot may not exercise the privileges of that rating until it is renewed - validity of the licence document does not cure a lapsed rating.