While surveying the seabed in Trondheimsfjorden, the Norwegian Navy found the wreck of the legendary flying boat Blohm & Voss BV 222 Wiking, which was sunk on 10 October 1945. They also found a Heinkel He 115.
The two wrecks are located at depths of 318m and 253m, a few kilometres from Trondheim city centre, and have never been visited by divers or underwater vehicles before. The Norwegian Navy located the wrecks using a Hugin AUV, an autonomous wireless underwater robot that can be programmed to map the seabed with sonar.
Hugin is one of the world's most advanced underwater vehicles and can dive to a depth of 6,000m. However, it must maintain a certain height above the seabed to avoid the risk of getting stuck in the wrecks. As a result, the minesweeper squadron did not get any good close-ups of the aircraft, and it was only when a team from Blueye Robotics dived down with two X3 underwater drones that the wrecks could be documented.
The drones were equipped with a multibeam sonar for navigation as well as four extra lights to get the best possible images. At 318m, the wreck is the deepest ever dived by a Blueye drone.
Six-engine flying boat
Divers and history enthusiasts have been searching for the wreck of the six-engine flying boat Blohm & Voss BV 222 Wiking for decades. The aircraft was the largest seaplane built by the Germans during the war, with a wingspan of 46m and a capacity of 92 soldiers.
The second aircraft that has been found is a Heinkel HE-115, identified as S4+DK (or S4+DH, according to Chandos Publications). This type of aircraft is well known in Trondheim, as there are two such wrecks at a depth of around 40m in Ilsvika.
Both of these wrecks can be dived, and Blueye Robotics has visited them a number of times. They have published videos from these wrecks on their Facebook page.
Reminders
The wreck discoveries provide valuable insight into the wartime activities that took place both above and below the surface of the Trondheimsfjord. As we approach 80 years since the end of World War II, they serve as tangible reminders of Norway's war history and its lasting impact.
"Exploring what lies beneath the surface has been a key driver for the Blueye team since day one," said Jonas Follesø of Blueye Robotics. He said that as the company's technology has matured, it has extended its reach to go deeper and operate longer.
The integration of additional equipment, such as underwater positioning and sonar, enables the drones to locate wrecks, even at great depths, quickly. "We've gradually become familiar with some of the history at the bottom of the Trondheimsfjord," said Follesø.
