Aircraft Nationality and Registration Marks
Nationality
Every aircraft engaged in international navigation must have a nationality, determined by registration in a State (Chicago Convention Articles 17-21). The State of registry exercises jurisdiction over the aircraft. An aircraft cannot be validly registered in more than one State; transfer of registration must follow the laws of both States. The registration mark and nationality mark together identify the aircraft.
Marks and display
ICAO Annex 7 governs nationality and registration marks. Nationality marks are letters (e.g. G-, N-, D-), registration marks are letters/digits. Marks must be painted or affixed permanently, with specified size and contrast, on the fuselage and, for some aircraft, under the wings. The certificate of registration must be carried on board under Article 29.
Traps
- Confusing the nationality mark with the registration mark - questions often ask which part identifies the State.
- Assuming the operator's State is the State of registry; they can differ (e.g. leased aircraft).
- Forgetting that a temporary registration or ferry permit may exist but still requires a State.
- Sizes/positions: examiners test whether marks must be visible from the ground and sides, not just the tail.
Worked example
An aircraft registered as G-ABCD: "G" is the nationality mark (United Kingdom), "ABCD" is the registration mark. If asked where the marks must appear, answer: on the fuselage (both sides) and, where required, on the lower surface of the wings - permanent, legible and contrasting.
Rule of thumb
Nationality = State; registration = individual aircraft. No dual registration allowed.