Crew transfer
Usually crew transfers in the North Sea is operated with helicopters. This form of transportation has strict demands when it comes to weather conditions, and as everyone knows the weather can be very unstable in the North Sea. Cancelations of helicopter departures results in very high extra costs for the operators as they can't get crew going of duty back home and the next crew out.
Using high speed vessels which is specialized this crew transfers although can be completed in a safe and comfortable way.