Port and starboard vessel's starboard side by green and its port side by red. Aircraft are lit in the same way. Port and starboard Port and starboard are nautical and aeronautical terms of orientation that deal unambiguously with the structure of vessels and aircraft. Their structures are largely bilaterally symmetrical, meaning they have mirror-image left and right halves if divided long-ways down the middle. One asymmetric feature is that on aircraft and ships where access is at the side, this access is usually only provided on the port side. To understand which is which, when a person is facing the bow on a
Mistral-class amphibious assault ship scaled-down versions of the BIP-19 design and with a common beam of : BIP-13 (13,000 tonnes, ), BIP-10 (10,000 tonnes, ), and BIP-8 (8,000 tonnes, ). BIP-8 incorporated features of the Italian amphibious transports, but included a helicopter hangar. At the design stage, the NTCD concept featured an aircraft lift on the port side (like the U.S. ), another on the starboard side, one in the centre of the flight deck, and one forward of the island superstructure. These were later reduced in number and relocated: a main lift towards the aft of the ship was originally located to starboard