Captain Hedley Kett, who has died at 100, was anchored off Sea Eagle by Lisahally at Londonderry in command of the U-class submarine P-34 when he received an order from WWII leader Winston Churchill in January 1943.
"Give your vessel a name," was the message to Kett and all the other Royal Navy submarine commanders out there fighting at sea. The Prime Minister believed that strong-sounding names would put the Germans on edge. Hedley duly obliged and called his sub Ultimatum.
"My crew agreed there was no better name," he explained later. "We'd an ultimatum to help win WWII." So far there has been no other ship or submarine of that name in the Royal Navy.
Captain Kett remained with Ultimatum for two years patrolling in the dangerous waters off Iceland and in the Mediterranean.
Ultimatum survived the war, as did Captain Kett, who was awarded a DFC and Bar for his distinuished service. He commanded other subs but always had an affection for Ultimatum and her crew. He made several peacetime visits to Sea Eagle and was often asked about the Ultimatum name he had given his sub.
By the end of the war, one in three British submariners had lost their lives, and of 18 officers on Kett's submarine captains' course, only two survived the war.
Kett, who was born in the Lea Valley on July 28 1913, left the Navy in 1946, when he received his licence as a North Sea pilot. He continued to be an active member of the RNR, commanding the submarine Springer during his annual fortnight's training in 1950. Kett, an ADC to the Queen, married Doris May Mitchell in 1942. She died in 2006 and he's survived by their two daughters.