Originally Posted by
Maclovin
Pumaboy makes a fair point. In 2009 a dive support vessel recovered a Superpuma from 100 meters of water in the Millar field in the North Sea in under 2 days. But they were not using navy divers breathing air, with a bottom time of 10 mins. They were using teams of commercial saturation divers which gave them the capability to keep the divers working at depth around the clock continuously until the task was completed. While the Grainneuail is more than capable of lifting 7 tonnes from the seabed she is not equipped to support saturation divers. I think Pumaboy is correct in his assertion that the wreck would be recovered by now in the North Sea (which btw isn't exactly renowned for calm weather or slack tides). You have to wonder if naval service divers and the Grainneuail are the right choice for this particular task, given the depth and the restrictions of their capabilities, and the fact that time is a factor where families are concerned.
Couldn't agree more. A proper DSV has dynamic position so it can 'hover' in a fixed position close to a hazard (rock, platform etc.) and withstand significant weather (wind, waves, current etc.) due to powerful engines and bow/azimuth thrusters. The dive bell is 'heave compensated' so the divers are immune to the heave of the vessel due to the waves. And the saturation divers can stay on the bottom for hours. The vessel would have the job done is a day or two.