The Iolair (Gaelic for eagle) is an oil rig that served as an emergency support vessel (ESV). She was built by BP to assist oil platforms in the field. The Iolair is a a self-propelled, twin hull, semi-submersible type vessel and can operate as a dynamically positioned (DP) drilling vessel.
In her early years, she was positioned in the BP Forties Oilfield. In 1995, she was sold to US drilling company Reading & Bates. She was converted to a workover/well intervention vessel and was stationed west of Shetland. The modifications included removal of some of the top structures, removal of the fire-fighting systems, closing of the dive tube and wave surge tank and the addition of a large derrick set and well stimulation equipment.
The Iolair can operate up to a water depth of 488 m, is 102 m long and 51 m wide, and has 207 beds with single and double occupancy.