When nuclear submarine HMS Conqueror sped down the slipway at Birkenhead in 1969, no-one suspected it would one day sink an Argentinian battleship half way round the world.
The 5,400-ton vessel, built by Cammell Laird at a cost of £30 million, was designed to hunt down and destroy Soviet subs.
But in May 1982, it was pressed into service in the Falklands conflict.
Conqueror became the first nuclear-powered submarine to fire in anger when it launched three Mark 8 torpedoes at the armoured cruiser General Belgrano.
Two struck the ship and exploded – and 20 minutes later the Belgrano was sinking rapidly. A total of 323 men were killed.
After the war, Conqueror returned to its Faslane base flying a Jolly Roger flanked by torpedoes – customary practice for a Royal Navy submarine involved in action.
Launched by Lady Selina McGeogh and her husband Vice Admiral Sir Ian McGeogh on 28 August 1969, the Churchill-class Conqueror was the last nuclear sub built by Cammell Laird.
The whereabouts of Conqueror, nicknamed ‘Conks’, were classified for most of the submarine’s working life.
But Liverpool saw the sub again in August 1979 on a five-day stopover at Seaforth. The public were even allowed to go on board for two afternoons.
Two other nuclear submarines were built at Cammell Laird’s Merseyside shipyards in the 1960s. They were the larger ballistic-missile subs HMS Revenge and HMS Renown.
The Resolution-class vessels weighed 8,400 tons submerged and had an unlimited range. Each carried a complement of 16 Polaris missiles in two rows of eight.
Renown was launched at Birkenhead on 25 February 1967 with celebrating Cammell Laird workers riding high on her deck.
Everyone wished Renown good luck on the day, but her 27 years of service were dogged by problems.
The submarine collided with other vessels, leaked radiation from her nuclear reactor and underwent a £155 million refit which took five years instead of two.
Her sister sub Revenge was commissioned at Birkenhead on 4 December 1968.
An army of cleaners moved in before the big day to ensure Revenge was looking her best. They proudly posed, mops in hand, on the sub’s deck.
But there was no-one prouder than Chief Petty Officer Frank Parr whose two-year-old son Andrew was allowed to attend the event.
As the commissioning ceremony unfolded, Andrew sat quietly behind his Dad eating his sweets!