ABP Southampton: NOTICE IS HEREBY GIVEN that some ships have a pilot transfer arrangement consisting of an accommodation ladder / pilot ladder combination with a trapdoor that does not meet IMO standards in effect since at least 2012.
A portable pilot unit (PPU) is a portable navigation aid system designed specifically for ship pilots, such as the SIRIUS series from TRENZ in Germany (www.trenz-ppu.com).
Pilots are expert ship handlers who possess detailed knowledge of local waterways. They are transported by high speed "Pilot Boat" or helicopter from shore to an inbound ship and from an outbound ship back ashore. Most ports have compulsory pilotage.