Država, katere ladje plujejo pod njeno zastavo, lahko zahteva, da so mednarodni radijski razpoznavni znak (IRCS) ali pa črke in številke registracije napisane na vrhu krmarnice, tako da so dobro vidne iz zraka, v barvi, ki je v kontrastu z osnovno barvo plovila.
The flag State may require the international radio call sign (IRCS), or the letters and numbers of registration, to be painted on top of the wheelhouse, so as to be clearly visible from the air, in a colour contrasting with the ground on which it is painted.