Kombuispraat

RELATIVE MOTION ILLUSION

City of Rotterdam’s pilot’s spatial awareness was distorted during the 5 minutes preceding the vessel’s collision with Primula Seaways. During this period, he had been drawn to the bridge window located directly above the starboard VHF radio that was angled off the perpendicular to the vessel’s centreline. As a result, the pilot experienced a relative motion illusion in which the vessel appeared to be heading in the direction in which he was looking. The likelihood of the pilot experiencing this illusion has been confirmed through an analysis of the information recorded on the vessel’s VDR, simulation (paragraph 1.12), the experiences of pilots who have worked on board either City of Rotterdam or City of St Petersburg (paragraph 1.10), and the experiences of MAIB inspectors and an ergonomist during pilotage transits in and out of Newcastle, UK (paragraph 1.11). During the passage along the Bull Channel, City of Rotterdam’s pilot had moved between the navigation workstation and the forward conning position as he monitored the vessel’s position by eye, radar and ECS. The pilot had recognised that the car carrier had been set to the north of its intended track by the wind. He had also realised that he needed to manoeuvre the vessel further to the south in order to pass Primula Seaways port to port. However, between the pilot calling the VTS at 2035 and the collision, it is likely that he would have spent much of the time looking through the window above the starboard VHF radio. Relative motion illusion deceives a viewer into thinking that the observed view is the direction of travel. In this case, the pilot was looking through the window above the starboard VHF radio, which was 33° off-axis from the centreline. As it was dark, the inward slope of the window removed all objects in the periphery, and there were no visual clues, such as a forward structure or bow tip, the illusion would have been compelling.