SpaceX semi-submersible heads to yard for ‘space age’ refit

The semi-submersible Deimos was towed from SpaceX’s Starbase facility in Brownsville, Texas to the Mississippi shipyard, arriving 5 March, according to the vessel tracking site MarineTraffic.com. Images and video posted on Twitter by @SpacePadreIsle showed Deimos being towed from Brownsville by the offshore towing vessel Signet Warhorse II, owned by Houston-based Signet Maritime.

Last year another ENSCO 8500 series semi-submersible, Phobos, arrived at the shipyard for conversion under the same contract from SpaceX. Both Deimos and Phobos are being converted to floating launch platforms to support launches and landings of SpaceX’s Starship next generation launch vehicle. Incorporating a spacecraft and super heavy rocket, Starship is a fully reusable transportation system designed to carry crew and cargo to Earth orbit, the Moon, Mars and other interplanetary flight.

“Ocean spaceport Deimos is under construction for launch next year” said SpaceX chief executive Elon Musk in a tweet in May 2021.

Through a subsidiary, SpaceX purchased both ultra-deepwater semi-submersibles (ex Valaris 8500 and 8501) from Houston-based drilling contractor Valaris, which received net proceeds of US$4M for each vessel.

Based on ENSCO 8500 Series designs, the semi-submersibles were capable of drilling in up to 2,600 m of water, with a 2M lb quad derrick, offline pipe handling capability, automatic station-keeping ability, and 150-person living quarters. Conversion work involves removing the drilling equipment.