Poland's navy said Thursday that it identified a sunken shipwreck in the Baltic Sea as almost certainly being Nazi Germany's only aircraft carrier, the Graf Zeppelin — a find that promises to shed light on a 59-year-old mystery surrounding the ship's fate.
The Polish oil company Petrobaltic discovered the shipwreck on July 12 on the sea floor about 60 kilometers (38 miles) north of the port city of Gdansk. Suspecting it could be the wreckage of the Graf Zeppelin, the Polish navy sent a survey vessel Tuesday, navy spokesman Lt. Cmdr. Bartosz Zajda said.
"We are 99 percent sure — even 99.9 percent — that these details point unambiguously to the Graf Zeppelin," Dariusz Beczek, the navy commander of the survey vessel, ORP Arctowski, said after returning to port Thursday morning.
At sea, naval experts used a remote-controlled underwater robot and sonar photographic and video equipment to gather digital images of the 260-meter-long (850-foot-long) ship, Zajda said.
"The analyses of the sonar pictures and the comparison to historical documents show that it is the Graf Zeppelin," Zajda told The Associated Press.
Measurements match the carrier’s
Zajda said a number of characteristics of the wrecked ship exactly matched those of the Graf Zeppelin, including the ship's measurements and a device that lifted aircraft onto the launch deck from a lower deck.
The experts were still waiting to find the name "Graf Zeppelin" on one the ship's sides before declaring with absolute certainty that it is the German carrier, Zajda said.
The Graf Zeppelin was Germany's only aircraft carrier during World War II. It was launched on Dec. 8, 1938, but never saw action due to Hitler's disenchantment with his navy and political squabbles in the Nazi high command. After Germany's defeat in 1945, the Soviet Union took control of the ship.
On Aug. 16, 1947, Soviets used the ship for target practice, filling the hold with munitions before practicing dive bombing techniques on it. The ship eventually sank, but its exact position has been unknown ever since.
Nick Hewitt, a historian at the Imperial War Museum in London called the Graf Zeppelin "a fascinating what-if."
"Nobody really knows that much about her," Hewitt told the AP by telephone. "You get a look at what she was like, whether she had an armored deck and all that sort of stuff, and you can figure out what she might have achieved."
‘Enormous impact’ on war unrealized
Hewitt said the carrier could have had "an enormous impact" on the war, likely wreaking havoc on Britain's convoy lanes in the North Atlantic.
Polish navy researchers will continue to examine the material gathered during their two days at sea, but further exploration of the wreck will fall to historians and other researchers, Zajda said.
The Graf Zeppelin will almost certainly remain on the seabed.
"Technically, it's impossible to pull it out of the water," Zajda said.
Krysztof Grabowski, a spokesman for Petrobaltic, said one of his company's ships discovered the wreckage July 12 after taking measurements of water depth in their undersea oil fields.
"We knew that there was something lying on the seabed near our oil fields because fishermen kept losing their nets there," he said.
He said his company took measurements and pictures of the seabed, discovering the wreck 86 meters (280 feet) below the water's surface. They suspected it could be the Graf Zeppelin because of its size, and passed on their information to the navy.
"Our people are always interested in searching for shipwrecks, so when they found this huge wreck they were of course trying to see what it could be," Grabowski said.
"They are proud and happy, because it was the discovery of a lifetime."