Interocean II

Rig:

Interocean II Jack-up

Date:

08 November 1989

Location:

Southern North Sea, UK Continental Shelf

Activity:

Rig move

Summary

Whilst on tow to a new location in the North Sea, the Interocean II ran into a gale with 85 mph winds and 25 foot seas. After losing one of its towlines, the UK coast guard was notified and two choppers were scrambled from Bristow's North Denes base in Norfolk to extract 43 of the rig's 51 crew. The first chopper reached the rig 30 minutes later to find the rig pitching and rolling, with the helideck tilted at 10 degrees. In driving rain, with the rig heaving up to 25 feet, the first 10 crew were airlifted and flown to a neighbouring platform.

The second chopper arrived to find the rig corkscrewing in heavy seas, resulting in the need for the pilot to reverse his chopper onto the helideck. After two more extractions, only 11 men were left on board, of which eight were expecting to remain behind as a skeleton crew. The first chopper returned for the last extraction but was unable to find the rig as the final towline had parted, allowing the rig to drift away. It became obvious that this would be the last landing attempted and the remaining crew were advised to abandon the rig due to the increasingly difficult conditions. The last 11 men had to crawl across the helideck before the chopper departed. Several minutes later, the Interocean II capsized and sank as a result of structural failure and flooding.

Helicopter Captains Gregg, Wood, Moon and Williams all received the Queen's Award for Gallantry for the courage shown during the rescue.

Sources:

Swiss Airline Pilots Association: Newsletter PDF document
International Maritime Organization: Sub-Committee on Stability and Load Lines PDF document

Photos
1. Fleumer Aerophoto