The Prince of Wales started up a power boat that took part in the D-Day landings - and then smiled when he was told it was now powered by German engines.
MGB 81 was one of a group of boats that were brought over from Portsmouth to the Caen Canal at Pegasus Bridge to take part in the commemorations.
On D-Day it was one of the lead boats for the British and Canadian troops landing at Sword Beach.
Since then it has been immaculately restored, and equipped with V12 engines donated by the German company MAN.
“It is ironic,” said skipper Richard Hellesdon. “He grinned.”
He added: “He started the engines for us. He had a big grin all over his face. Then he pressed the hooter. There was a big smile for that.”
As the Prince toured the boats, the Duchess met a group of veterans including Joe Cattini, 91, a gunner who landed with the Hertfordshire Yeomanry on Gold Beach.
Later he described how the landing craft in front of him hit a mine and sank. “The chaps were scrambling out as fast as they could. Some of them were swimming up to their necks in water. There were a few casualties that did not make it.”
In the last few days he has teamed up with his new friend Denys Hunter, 90 - a colleague from the same gunnery company he met by chance for the first time in 70 years in a restaurant after Mr Hunter recognised his tie.
Mr Hunter, from Romsey, Hampshire, said it was his first time back to Normandy. “It’s the last time I will ever get here,” he said. “At 90 I’ve not got much chance to come again. I suppose I did leave it a bit late. But there you are.”