Borr Drilling jackup Prospector 5 sinks off Gabon after punch-through, one dead and four missing
The rig had 115 people on board and was preloading for BW Energy's Dussafu programme when its leg broke through the seabed
Borr Drilling's jackup rig Prospector 5 sank off the coast of Gabon late on Saturday 24 October, killing one worker and leaving four missing. There were 115 people on board, and 110 were rescued. The rig was on location in the Dussafu Marin licence off Mayumba, near BW Energy's MaBoMo production facility, and was preparing to drill for BW Energy.
"Preliminary information indicates that the rig experienced a punch-through event during preload activities, resulting in loss of stability and the subsequent sinking of the rig," Borr Drilling said. The 2014-built unit had not yet started drilling.
The dead worker was an Indian national, said Sylvain Mayabi Binet, secretary general of Gabon's National Organization of Petroleum Employees. The four still missing are three Gabonese nationals and one other expatriate.
What is a punch-through?
When a jackup arrives on location it lowers its legs and preloads them, pumping in ballast to push the spudcans at their feet into the seabed until they hold more than the rig will ever put on them in operation. A punch-through happens when a leg breaks suddenly through a firmer layer into softer sediment below. The leg drops, the hull lists, and the rig can lose stability within moments. It is one of the most serious hazards in jackup operations, because it can come without warning, especially where a stiff crust lies over soft clay or the silt is uneven and the seabed appears stronger than it is.
What happens to the search and to production?
Borr chief executive Bruno Morand said the company is concentrating on the search and on the welfare of everyone involved. "We are deeply concerned for those who remain unaccounted for and everyone affected by this incident," he said. Gabon's Ministry of Petroleum and Gas has set up a crisis unit with the navy, the state oil company Gabon Oil, BW Energy and Borr, told the navy to reinforce the search, and ordered a technical investigation.
Production on the licence has been halted. Panoro Energy, which holds 17.5% of Dussafu Marin against BW Energy's 73.5%, said there were no reports of damage or accidental discharges. The ministry said no discharge of harmful substances had been seen and that pollution-response equipment has been deployed to protect the coastline and Mayumba National Park.
Prospector 5 went to Gabon under a binding award from BW Energy announced in April, covering four firm wells over a minimum of 320 days with options for another 220.
This story is part of the Maritime Briefing of 28 October 2026.
