The largest warship ever built in the UK eased into the Firth of Forth as it set out on two years of sea trials

HMS Queen Elizabeth, the Royal Navy's new aircraft carrier, left her dock in Scotland in a delicate operation that took around three hours.

She is named after Elizabeth the first and is the second ship to carry the name - the first was a First World War battleship.

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Image: The £3bn ship and her 700 crew ease away from the dock

More than 700 crew are onboard, from seamen to aircraft engineers, dentists to force protection. The oldest crew member is 58 and the youngest 17, although the average age is in the early twenties.


In recent weeks they have been practising drills and familiarising themselves with their new ship.

Sailing her out of the basin she was built in needed precise calculations and nerves of steel. At high tide, she was guided through a narrow exit in the harbour. This had been widened but still only allowed 14 inches either side to spare.

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Under the water line there was just half a metre between the bottom of the ship and the seabed.

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The carrier then dropped anchor after just a few hundred metres.

At low tide, she will make her approach towards the three Forth bridges close to midnight, sailing at 3-4 knots; any faster and suction will pull her downwards into the river - an effect known as 'squat'.

The first two road bridges can flex by up to three metres in high winds but the third, the iconic Forth Bridge, poses its own challenge - height.

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A radar mast will be hydraulically lowered to make room for the ship to pass underneath. Even so, were a person to stand on the highest point of her, and reach up, they would be able to touch the Forth Bridge as they sailed through.

"It is like driving your car into a car park you go 'oh my god' and dip in your seat. It is exactly the same feeling as that," said Captain Jerry Kyd, who has previously commanded the UK's last two aircraft carriers HMS Ark Royal and HMS Illustrious.

The whole process could take more than 10 hours.

The following six weeks will be spent in the North Sea and Moray Firth "proving systems" - she will finally sail into her home port of Portsmouth sometime in the autumn.

Flight trials will begin off the eastern seaboard of the United States in October 2018.

Image: Royal Navy Leading Hand Claire Butler, the first crew member to join the aircraft carrier

HMS Queen Elizabeth has taken more than eight years to build and is the first of two new carriers for the Navy; a second, the Prince of Wales, will follow in two years' time.

Together they will cost over £6bn, a price tag which the ship's first commanding officer defends as value for money.

"You look at all the premier nations around the world and why is it that every nation in the top tier are investing billions of dollars in aircraft carriers? Is it just us or has everyone got it wrong here?" Cptn Kyd points out.

"The reason being is they provide the government, very simply, with an incredibly flexible tool that is not just about war fighting.

"This is about deterrence, coercion, political signalling and providing a huge sea base - don't forget it is not a ship - it is a sea base for disaster relief, humanitarian assistance, defence engagement and selling British industry abroad."