A 7-meter autonomous surface vessel (ASV) was recently deployed to support offshore services provider Subsea 7 during pipelay operations off the coast of Egypt.
The C-Worker 7 vehicle manufactured by U.K. firm ASV Global was fitted with a survey suite comprising a multibeam echosounder and side scan sonar in order to carry out touchdown monitoring in support of the pipelay vessel Seven Antares.
A custom payload frame was designed to house the survey suite specified for the mission. The modular frame slotted into the C-Worker 7’s moonpool to mount and deploy the sensors. Extensive testing confirmed that repeated sensor deployment was achieved within millimeter accuracy ensuring that no further survey sensor calibrations were required. Vessel trials and testing took place in the Solent, U.K. before the vessel was mobilized from ASV’s U.K. headquarters.
The C-Worker 7 was operated for a total of 37 days. Throughout the operation the vehicle was controlled and monitored using the ASView control system from a control station set up onboard the Seven Antares. Subsea 7 Survey personnel piloted the C-Worker 7 and operated the survey sensors to ensure data accuracy and quality.
Use of the vehicle replaced the need for an additional survey vessel, thereby resulting in significant cost savings and also providing greater operational flexibility due to its better endurance and improved availability compared to an equivalent manned vessel. In addition, use of the vehicle resolved the technical challenge of surveying in very shallow waters while also removing the risk to personnel working at sea in small craft.
“The C-Worker 7 has proven to be a very capable vessel providing an excellent stable survey platform controlled by the Pipelay Vessel,” said a spokesperson from Subsea 7.
Richard Daltry, Technical Director at ASV Global, said, “We are delighted to be supporting Subsea 7 in their quest to increase operational efficiency through the use of autonomous surface vessel technology. This operation marks a huge step in realizing the potential of this technology and goes a long way to prove its operational readiness, particularly in a demanding offshore environment.”