NAVAL divers tried in vain to rescue the crew of the oil rig support tug Bourbon Dolphin which capsized off the Shetland Islands.

A four-strong team from Northern Diving Group battled horrendous conditions to try to get inside the upturned hull of the vessel, which capsized while working with the rig Transocean Rather.

Five crew from the support ship were still unaccounted for as the NDG team arrived from Faslane, via RAF Lossiemouth.

They had barely arrived back at HM Naval Base Clyde from a call-out dealing with suspected unexploded ordnance when the SOS came from the rig in the Rosebank oil field, roughly 75 miles west of the Shetlands.

At first the divers tried to manoeuvre a robot submarine inside the stricken vessel.

Currents and Atlantic swell made it impossible for the submarine to enter, so it was left to the NDG divers – WO Steve Strange, CPO Willie Sharp, LD ‘Faz’ Farrell and D1 John Anderson – to do it manually.

With the hull moving violently up and down in the heavy swell, there was a great danger of the frogmen being sucked into the ship.

They managed to get inside the Bourbon Dolphin’s bridge – where there was no sign of the missing crew – but after three dives, the team decided it was too dangerous to continue.

“This was not a run-of-the-mill job – this was extreme diving. My team did a bloody amazing job,” said Lt Cdr Andy ‘Sharkey’ Ward, NDG’s Commanding Officer.

“Swell makes things tricky and the currents were intense. You’ve got an upturned hull, water being sucked in and out, doors opening and closing.”

All the time there was the threat of the tug sinking, taking any divers down with her to the bed of the ocean, one thousand metres below.

“There was still some hope that there might be someone alive in an air pocket – if it had not been a question of saving lives, then my team would not have gone in,” Lt Cdr Ward added.

“In the end, they realised that it was far too difficult.”

Five people died in the tragedy, including the son of the tug’s skipper, who was on work experience with the vessel. Four days after capsizing, Bourbon Dolphin defeated salvage efforts and sank.