Amprion has identified wreckage from a US B-17 bomber near the planned DolWin delta converter platform during ordnance inspections for the DolWin4 offshore grid connection.
The company said the pieces of wreckage were located about 260 metres from the platform centre and were found during routine checks last summer.
It added that the US Air Force in Ramstein and the Defense POW/MIA Accounting Agency were notified and oversaw investigation work on board the survey vessel.
Rheinmetall EOD Services examined the site from mid-November to Christmas 2025 to determine the condition of the aircraft, whether any ordnance remained onboard, whether serial numbers could identify the plane and whether there were signs of human remains.
The investigation used electromagnetic sensing to map the wreck, which lay under about 1.5 metres of sediment, before sections were exposed and inspected with DPAA assistance.
Amprion said the bomb bay was accessed through opened hatches and found to contain no bombs, and the area around the wreck has been cleared for further project work.
Additional findings and questions regarding identification and possible human remains are being evaluated in coordination with German authorities and the DPAA.
Amprion stated that protecting employees and the environment, and treating any potential war graves with dignity, are priorities.
DolWin4 and BorWin4 are scheduled to go online in 2028 with cables linking North Sea wind farms to the Hanekenfähr substation in Lingen to deliver 1.8GW of offshore wind energy.