But they underestimated how fast the industry would embrace ultra-large turbines and move into greater water depths. The vessels they had built were suddenly looking too small for the task at hand.

Some major contractors, such as Fred Olsen Windcarrier and A2Sea, have subsequently fast-tracked upgrades to their flagships, adding longer legs and taller, beefier cranes to meet developer demands on high-profile projects including East Anglia, Hornsea and Dudgeon.

Others