OceanGate was contracted by Argus Expeditions to provide a manned submersible and marine operations team on an expedition to survey the iconic wreck of the Andrea Doria, an Italian flagged passenger liner that sank near Nantucket after colliding with the Stockholm, a Swedish passenger vessel outbound from New York.
The primary objective of the Andrea Doria Survey Expedition was to capture sonar images of the shipwreck to document its current condition. The expedition goal was to establish accurate and reliable baseline data so explorers and scientists can better assess the decay of the wreck over time.
This iconic shipwreck has been explored by scuba divers and mixed-gas divers for decades – with the first dive occurring within hours of the sinking. These scuba dives have resulted in limited views of the wreck due to the short bottom time available to divers (approx. 20 minutes per dive) and limited visibility.
Because divers can only spend a few minutes at depths of 240 feet, and because water turbidity limits visibility to a few dozen feet, it is nearly impossible for divers to capture images of the full scope of this 697 foot long shipwreck. Divers just cannot spend enough time or see well enough to fully view the wreck. Plus, as the ship decays, the familiar landmarks that divers use to navigate around the vessel are changing or disappearing. As a result there are no images that fully illustrate the scope of the wreck in its current state.
The expedition team boarded the offshore support vessel Warren Jr. and departed Boston, Massachusetts on June 2, towing Ms.Lars and Cyclops 1 to the site of the Andrea Doria.
Dive operations commenced and Cyclops 1 became the first manned submersible to explore the legendary shipwreck since 1995. Due to diver reports of fishing nets floating above the center of the wreck, the team chose to approach the wreck at the bow. Use of the iXblue PHINS inertial navigation system allowed the pilot to approach the wreck at the planned point.
The expedition plan called for first sonar scanning the wreck from a safe distance (30 meters) to better assess any entanglement hazards before approaching the wreck for visual inspection. The ship is laying on her starboard side with much of the superstructure having collapsed to the sea floor, leaving the keel side of the vessel relatively clean and free of hazards. Beginning at the bow, the team planned to circumnavigate the wreck, first working along the keel side of the wreck, making sonar scans at specified spots, to create a virtual map of the entire wreck.
The dive team conducted dives of nearly four hours and performed 17 sonar scans of the wreck – focused on the bow of the vessel. Subsequent dives to continue exploration of the wreck were scrubbed due to adverse weather conditions. A combination of high winds, heavy seas, and thick fog prevented the team from conducting more dives. At times, the fog limited visibility to a few hundred feet. Safe submersible operations require surface visibility of one mile so that the surface operations team can see the submersible at the end of the dive. Heavy seas also limit the team’s ability to see the submersible at the surface due to its low profile in the water.
Although weather conditions prevented the team from conducting as many dives as planned, the crew did successfully capture the first detailed sonar scans of a portion of the wreck and of seabed scouring around the wreck.
From the data that we did collect, it appears that the wreck continues to decay, possibly at an increasing rate. Although this conclusion is uncertain due to the limited exploration of the entire wreck. Comparing our results to previous low-resolution sonar scans, it does appear as if pieces of the wreck have fallen away.
We plan to revisit the wreck in 2017 and beyond to continue mapping the wreck.