AF447 Atlantic Search
Date: Q1 2010
Prior to the acquisition of Seabed AS by Swire Pacific Offshore in February 2012, Seabed AS, was awarded a contract by Bureau d’Enquêtes et d’Analyses (BEA) to support the search and recovery of the AF447 aircraft.
Stage 1 – Desktop Study
Seabed AS worked with BEA during the desktop study investigation phase. The appropriate available data, maps and images were gathered and examined to assess the exact location of the target.
Stage 2 – The Spread & Mobilisation Phase
Seabed AS mobilised a fibre rope wreckage recovery solution, deployed from the 30 tonne winch and operated over a customised tower from Seabed Worker’s deck. The vessel then sailed from Bergen to Cape Verde where project personnel were placed onboard. Thereafter, Seabed Worker transited to Recife in Brazil, where three unique ultra-deepwater Remus autonomous underwater vehicles (AUVs) were fitted onboard. This equipment was sourced from Woods Hole Oceanographic Institute and Geomar, with the capability of pinpointing wreckage at depths down to 6,000m. Three vehicles were chartered due to the added efficiency this provided, the need for which was driven by the large surface area that had to be surveyed.
Seabed Worker back deck arrangement during deepwater cargo recovery operations, using a 6,000m fibre rope deployed through a customised winch and tower system
Swire Seabed’s Triton XLX ROV was maintained onboard and was to have been utilised in case of the search continuing into recovery phase. A deep-towed side scan sonar array was then mobilised onto a third party vessel, meaning the two vessel spread was prepared to cover all phases of the operation: towed side scan sonar for trawling a vast space at good speed during the search phase; AUVs for pinpointing the location of the wreck; and ROVs to take close-up video footage and then to position slings around specific parts of the sunken plane prior to lift and recovery using the fibre rope. Seabed AS was instrumental in defining and project managing the spread required for the search operation.
Stage 3 – The Search
Seabed Worker undertook the search phase at or close to maximum accommodation capacity throughout the operation. The vessel’s 66 berths were occupied by regular ROV and marine crews as well as specialist project personnel, client representatives, French naval personnel and various other stakeholders. The vessel undertook AUV operations for a period of 60 days, with the greatest challenges being the undulating seafloor terrain, significant operating depths down to 6,000m and the logistical complications of coordinating a wide range of parties in a foreign environment. The AUVs generally functioned smoothly throughout and there were no major breakdowns, which was impressive in the context of the large number of dives undertaken.
