The Queen Mary had a serious incident in Cherbourg in the 1950s. I don't recall which captain, but it was his first command of the Queen Mary when on departure the wind pushed the Queen into a part of the harbor in which there were some WW2 submerged wrecks. The Queen Mary fouled here screw on some underwater debris, trapping her for some time.
Commodore Marr was her Master at the time.
During WW2 part of the sea bed in the harbour had been deliberately strewn with anchor cables in defence of the town.
As we sailed in and out of Cherbourg last October, it was interesting to see the entire area from the height of QM2's Observation deck