The weekend marked 75 years since Australia’s worst maritime disaster. Only now are the ill fates of HMAS Sydney and its German counterpart HSK Kormoran being understood- all thanks to recent 3D modelling and analysis by a team of international researchers.

All 645 of the crew of HMAS Sydney were lost.

On 19th November 1941, the pride of the Australian Navy, HMAS Sydney II, a state of the art cruiser that had already won several battles, disappeared in home waters off the Western Australian coast. When a search for the famous ship was commenced, hundreds of sailors were rescued from small boats… but they were all German Navy crewmen.

These enemy sailors told an improbable story of how their disguised and heavily armed converted merchant ship HSK Kormoran had taken Sydney by surprise, and that the two ships had mortally wounded each other in a close range fight. They claimed they had last seen Sydney on fire and headed south, before they abandoned their own cripple vessel. For many people, the fact that hundreds of Germans had survived while no Australians had seemed very suspicious.

Only two weeks later, Japan attacked Pearl Harbour, and the world was plunged even deeper into the largest war to have ever occurred. In the chaos and aftermath of a global war, no formal investigation was ever held, even though this was the worst loss of life in the history of the Australian Navy.

In the absence of physical evidence or formal conclusion, the events of that day moved into the realm of folklore and tabloid sensationalism for almost seventy years, with claims of war crimes and government cover-ups that made the lack of resolution for thousands of family members a life-long burden. The loss of HMAS Sydney with all 645 of her crew stands as a marker for when the Second World War came to affect Australia very directly.

To get stories like this delivered to your mailbox every week,

subscribe to the weekly Spatial Source newsletter.

In 2008, after a years-long struggle to raise enough funds, the wrecks of both Sydney and Kormoran were found by the not for profit Finding Sydney Foundation, who employed renowned shipwreck finder David Mearns to plan and execute the search. In a process very similar to the recent search for MH370, the wrecks were located using deep tow side scan sonar, and then inspected with both still image and video cameras mounted on an ROV (Remotely Operated Vehicle). The wrecks are 2500 meters deep, lying 20 km apart on an essentially flat seabed. At these depths there is no light, very little current and few species of marine life.

The results of the 2008 expedition were approximately 1,500 still images and hours of video footage that revealed the horrifying damage that both ships suffered. It was also clear that the German account was true, confirming that the battle that had occurred was one of the most unusual in the history of naval warfare. The success of the 2008 mission in locating and photographing both wrecks brought resolution to the whole community of families and experts involved in the Sydney and Kormoran story.

In 2011, Dr Andrew Hutchison of Curtin University’s School of Art and Design decided to see if the archive of visual material from 2008 could be used to tell this story to a wider, younger audience who had little or no familiarity of the Second World War.

Bill Aylott was lost with Sydney only weeks after this picture was taken on Circular Quay in 1941. His two children are still alive, and have lived their whole lives with doubt about their father’s fate.

“People don’t appreciate how critical the Second World War was, in terms of human cost, and also how it has directly shaped the way we live our lives,” said Dr Hutchison. “When I was growing up in the 1970s, war veterans were everywhere. They were the plumber, the bank manager, even your own father. But of course, it is very different now. The war stimulated huge innovations such as antibiotics, radar, jet aircraft, computers and digital technology.”

The plan was to use the existing material to create a 3D environment that allowed people to explore and discover the technology of the times, and the men who lived and lost their lives using it. The technique of using many images to produce realistic 3D models is variously known as close range photogrammetry, photogrammetric 3D’ reconstruction, Reality Based Modelling, or more simply, ‘photographic reconstruction’.

“Photo reconstruction has been around for a while, but its time has now come,” continued Dr Hutchison. “Digital cameras, faster processing power in computers and peoples’ willingness to interact with virtual, spatial environments has made this possible. So I wanted to use interactive media to tell this story, as this provides a now natural means to engage an audience.”

Andrew Hutchison has previous experience using photographic reconstruction in land based archaeology, architecture, town planning and rock art, but none of these had the problems of being underwater, at such depths. When the 2008 archive was examined in detail, it became clear that the number of images available were insufficient for the creation a 3D environment of the ships.

While the camera and lighting equipment used in 2008 was state of the art for subsea applications at the time, it was simply not intended to be used for photographic reconstruction.

Taking new tech underwater

In 2011, the interdisciplinary team at Curtin University started to explore a possible return to the wreck sites with the subsea research community.  It turned out there was plenty of appetite, based on a whole range of improved technology that had come into the market since the 2008 discovery of the wrecks.

Vessels had greater capacity to operate in adverse weather, ROVs had greater power, cameras were higher resolution, and lights more powerful. DOF Subsea, a supplier of subsea services to the international oil and gas industry, made the extraordinary offer to take the team back to the wreck sites at no cost, services which would have cost many hundreds of thousands of dollars per day at commercial rates.

With a return to the sites now possible, the Western Australian Museum joined the project. A sizeable grant from the Commonwealth Government Department of Heritage ensured there was funding to create the array of lights and cameras that would take hundreds of thousands of still images, and many hours of HD stereo video.

DOF Subsea’s brand new subsea operations vessel.

Each of the ships is the size of a large building, and they have been smashed and ripped apart, and the parts scattered around the sea floor to create a debris field hundreds of meters wide. Thousands of objects that fell off the decks, or out of the broken ships, lay around everywhere. The scope of the job is not just of two ships, but more like multiple architectural sized objects in a landscape covered in very fine detail of huge interest and importance. Because of this the team had to be able to record all of this in great detail.

A special IT system was designed to allow all of this material to be recorded from the seabed to the vessel- a total of 50 Terabytes of data. A team with very diverse skills in cultural heritage, engineering, surveying, logistics, manufacturing, photography and marine sciences was assembled to deal with the task at hand.

DOF Subsea provided not only the vessel, but planning, training and engineering support for the project in the two year lead up, and provided the specialist ROV pilots who had to actually navigate the ROVs through the tasks safely, in what turned out to be adverse weather conditions that tested the capacity of even the latest generation vessels.

Multibeam sonar scan of HMAS Sydney main wreck.

In four days of operation in early May 2015, approximately 500,000 still images and 300 hours of video material were gathered from the wrecks of both Sydney and Kormoran, as well as the extensive debris fields surrounding them. In addition, a multi beam sonar scan was made of the main wreck sites, and part of each debris field.

Samples of water, soil and marine growth were also taken from the wreck sites to contribute to the management plan that the Western Australian Museum will develop to monitor and protect the sites…

This is the first instalment in a 2-part exclusive article. Part-2 will be published in the coming weeks to reveal images from the expedition clues from the ships’ final moments.

Subscribe to our free weekly newsletter to make sure you catch part-2.