The latest edition to the Østensjø fleet was delivered from Astilleros Gondan SA, Spain on June 10, 2010.

The unique Voith Schneider tug, Vortex, is a Robert Allan design – AWT 37/80 – with a bollard pull of 73 tons, and can manage a speed of 14.5 knots. Vortex is equipped with Voith Schneider propulsion – is design for escort operations, harbour works as well as ocean towage. She is equipped with oil recovery and fire fighting equipment (FiFi1). Furthermore the tug is fully equipped for salvage in open waters.