Manoeuvring characteristics of the vessels at the head-on situation are examined in this study. The meetings between the power-driven vessels are considered based on their propellers. These vessels can either have a single propeller or double propellers. A vessel with a single right-handed propeller alters her course to port side easier than the starboard side. There exists an unnoticed gap, therefore the authors discuss the International Regulations for Preventing Collisions at Sea, 1972 (COLREGs), Rule 14, considering the vessel orientation based on its propeller walk. After presenting all possible cases and their probable consequences, this paper offers authorities to embed the information of propeller characteristics into the Automatic Identification Systems (AIS) in order to prevent misunderstandings during the VHF communications, probable collision risks and discussions on liability issues in case of marine accidents.