That sounds like the 'Merc Enterprise' rescue of January 1974. Five Culdrose Sea Kings, including two German a/c from the Foreign Training Unit (the others from 706 and 824 Squadrons) lifted seven crew from a 480 ton Danish coaster when hurricane force winds were blowing down the Channel, and a further four who had been picked up by a Soviet trawler. The ship had capsized off Plymouth. One of the German aircraft and the 824 aircraft suffered severe salt ingestion in the engines, and both made cautionary landings in fields on the way back to Culdrose. The turbine blades were found to have severe corrosion, and I understand the barn door FOD shield was introduced as a partial answer.
Those are the bare bones; I am sure that there is a lot more information available.