On December 20th, 1997 the Sikorsky S-76B helicopter PH-KHB was conducting a serie of shuttle flight sorties between rigs and platforms over the North Sea in the K5 and Pentacon field area. During the fifth sortie, after sunset and in dark night conditions the final approach to production platform L7-A resulted in a go-around. After a left turn a second approach was initiated. After power reduction to loose height and speed in a relatively short time the helicopter lost almost all forward speed and entered a steep descent towards the sea. The application of collective power could not prevent the helicopter entering the water. Crew and passengers were able to evacuate the helicopter. After approximately one hour in the water they were picked up by a supply vessel. During this period one passenger deceased.