Specifically, the recently launched "ABS Advisory on Autonomous Functionality" notes that autonomous vessels are still not in line with regulations of Flag states.

Traditionally, the United Nations Convention for the Law of the Sea (UNCLOS) assigns the obligation to ensure safety at sea with regards to the construction, equipment and seaworthiness of ships to the Flag States. Flag States carry out this responsibility by utilizing a certification and inspection regime in accordance with IMO rules and regulations to govern vessels flying its flag. In practice, a portion of this work is then delegated to the Classification Societies acting on their behalf.

Port States are responsible for vessels in its ports or domestic waters whether they be foreign or domestic vessels. Concerning foreign vessels, Port States have inspection powers to inspect and enforce compliance of these vessels to the applicable IMO regulations.

The advisory notes that

However, these vessels will have to comply with domestic regulations which are administered by the Port States. Where autonomous functions intended to be used onboard vessels are used only to augment and assist the crew’s duties, this would likely be allowed under the existing rules and regulations.

An example of the challenges arising from autonomous functions is an autonomous navigation system performing the duties of a Look-Out as required by COLREG (International Regulations for Preventing Collisions at Sea 1972) will present a challenge as this would be in conflict with the regulations. In most cases, the current rules and regulation will not allow the use of such autonomous functions.

Therefore, engagement with the vessel's flag state or port state is crucial for efficient operations. Overall, the designer would need to demonstrate to the relevant authorities that the safety level of the proposed autonomous function is equivalent to that when the task is being carried out by humans. An exemption from the affected regulation(s) would most likely be needed.

Concluding, the advisory highlights that the existing regulations can not be applied to the development of autonomous functionality; Yet, it is stated that a number of Flag Administrations have shown flexibility and are working with industry.