THE largest and most powerful ship ever built for the Royal Navy – part-designed by 170 Barrow shipyard engineers – has set sail for the first time.

Naval staff and contractors lined the deck of Queen Elizabeth as the 280-metre, 65,000-tonne aircraft carrier moved from Rosyth out into the Firth of Forth on Monday in a three-hour operation.

The £3bn behemoth, which is set to be the nation's future flagship, and her 700-strong ship's company are heading to the North Sea for maiden sea trials over the summer.

One of the most delicate manoeuvres of the six-week trials has already been completed just moving the ship from the dock.

Navigators, pilots and tug boats had the slimmest of margins to deal with to guide HMS Queen Elizabeth out of the Rosyth basin in Fife where she was assembled.

At high tide, the ship was taken through a narrow gate avoiding the dock walls by inches while under the water line there was just half a metre between the bottom of the ship and the seabed.

Once travelling just a few hundred metres in the Forth, the carrier dropped anchor in order to wait for the tide to lower, allowing space to pass under the Firth's famous bridges.

A total of 10,000 people worked on construction of the ship – which Furness engineers helped to design, made up in sections at yards around the UK and transported to Rosyth, where it was assembled.

Rear Admiral Keith Blount, head of the Navy's carrier programme, said: "This ship has been built in a very unique way – assembled in Rosyth but built around the UK in six different yards.

"This is the moment where that British shipbuilding expertise meets the professionalism of the Royal Navy to give us a ship to be proud of."

The second ship in the class, Prince of Wales , is being fitted out in the Rosyth dock and staff were able to look on as its sister ship set sail for the first time.

Tony Holberry, a director of the Aircraft Carrier Alliance, the group of companies that built the ship, was one of those watching on from Rosyth Port as the project he has been involved with for more than a decade came to fruition.

He said: "I was there before a contract was placed and I stood on the first piece of steel that was cut in Govan, and now look at it. It's a very proud day."

He laughed when asked if his work was now done.

"I think my job just starts actually, I've got to get the equipment on board, then transition it into the Navy, so this is just the start if the next part of the journey."

The sea trials will take place in the North Sea before the carrier returns to Rosyth for further checks and any adjustments.

Commanding officer Captain Jerry Kyd said: ''After that we're going back out for a further three weeks to test the ship on the more war-fighting capabilities - the radars, all the ship's sensors, radios and things like that.

''At the end of that period we know that all the basics work.

"She's done her test drive and after that we will go down to Portsmouth, the ship's home, and get her finally ready to join the Royal Navy fleet, hopefully at the end of the year.''

Defence Secretary Sir Michael Fallon said: "This is a historic moment for the UK as our new aircraft carrier takes to sea for the very first time.

"This floating fortress is by far the most powerful ship ever built in Britain that will enable us to tackle multiple and changing threats across the globe.

" HMS Queen Elizabeth is an enduring example of British imagination, ingenuity and invention that will help keep us safe for decades to come. She is built by the best, crewed by the best and will deliver for Britain.

"For the next 50 years she will deploy around the world, demonstrating British power and our commitment to confronting the emerging challenges from a dangerous world.

"The whole country can be proud of this national achievement."