Seaworker

Rocket Lab

Seaworker during an Electron recovery operation – Rocket Lab

Seaworker is a multi-purpose support vessel owned and operated by Seaworks. The vessel is periodically chartered by Rocket Lab in New Zealand to recover the Electron first stage booster, following splash down in the Pacific Ocean.

Electron is a two-stage small-satellite rocket. Initially planned as an expendable design, Rocket Lab pivoted towards reusability in 2019. The plan was to catch the first stage booster mid-air as it descended to Earth under parachutes. On early flights the company made no attempt to catch the booster, instead allowing it to soft-splashdown in the ocean to be recovered by a waiting ship. Seaworker was first used for the ‘Return To Sender’ mission in November 2020, which resulted in the first successful recovery of Electron.

Seaworker recovering the Electron first stage during the first recovery attempt, November 2020 – Rocket Lab

Seaworker has continued to be periodically chartered by Rocket Lab for recovery operations in New Zealand however the company does not currently make attempts to recover the booster for every flight. As Seaworker is a charter vessel, Rocket Lab installs and removes its recovery equipment each time. The recovery equipment primarily consisted of OCRA – Ocean Recovery & Capture Apparatus. This design was a hydraulic cradle that was used to haul the booster from the water and secure it for the voyage back to land.

Rocket Lab is still developing its recovery techniques and debuted an alternative recovery system in July 2023. Seaworker has a sister ship, Seasurveyor, which was chartered for launch 39 as Seaworker was not available.

Meet ORCA, our Ocean Recovery & Capture Apparatus for today's Electron recovery mission. This hydraulic cradle acts as a recovery-optimized strongback to safe Electron's booster, bring it out of the water, and keep it in place onboard our vessel for the trip home. pic.twitter.com/avFqjZ12ud
— Rocket Lab (@RocketLab) May 15, 2021

Rocket Lab was set to shift to mid-air recovery – catching Electron with a helicopter – under these plans, there would have been no requirement to charter a recovery vessel for each attempt. In 2023, following a number of unsuccessful catch attempts, Rocket Lab scrapped plans to catch the booster and focus on recovering Electron from the water instead, as they were already doing successfully.

Rocket Lab stated, “Extensive analysis of returned stages shows that Electron withstands an ocean splashdown and engineers expect future complete stages to pass qualification and acceptance testing for re-flight with minimal refurbishment.” As a result, Rocket Lab is abandoning the helicopter recovery concept in favor of the ship-assisted rescues.”