Measuring 270 metres long by 52 metres wide and with process and export capacity up to 130,000 barrels per day of oil and storage of up to 800,000 barrels, the Glen Lyon unit is one of the largest harsh-water FPSOs in the world.

But as BP floating systems engineer Karthik Nookala puts it, part of the reason the Glen Lyon is a “step-up technologically” was not only because of its size but also because a vessel so large has been deployed in the extremely harsh waters found to the west of Shetland.

“Glen