There may just be a possibility that the solution to long offshore flights, with an ability to hold a "hover" at the business end, could come in a completely novel way - HAV?
Loads of of problems to overcome, of course, and the discussion would move off the Rotorheads site on PPrune, but the oil industry may have to think laterally to move forward, or go further.
I flew the B 609 simulator back in 1998 and liked it immensely, my organistaion (corporate aviation) placed an order, but withdrew when the project became prolonged and somewhat indistinct. Whatever happens, the future will be fascinating and we must still be prepared for surprises. UG