Control tower lowered on to UK's biggest aircraft carrier

The UK's biggest aircraft carrier has moved a step closer to completion after its 750-tonne control tower was lowered on to the deck.

The aft island of HMS Queen Elizabeth was built in a yard on the River Clyde in Glasgow and sailed on a barge to Rosyth, Fife, last week to join the other parts of the ship.

It took workers in Scotstoun nearly two years to build the section which will serve as the centre of on-board flight operations.

A huge crane lifted it into place, and it was then lowered on to the deck yesterday in a ceremony with representatives from the armed forces in attendance.

A plaque with the badges of the Royal Navy, the Army and the RAF was placed under the aft island before it was lowered the final few feet into position.

Part of the plaque will remain visible and reads: "Embedded within are the emblems of the Royal Navy, the Royal Air Force and the British Army, the three services which together protect the United Kingdom, her overseas territories and crown dependencies across the globe."

Two apprentices, Gordon Currie and Chris McArthur, sounded airhorns to signal the start of the lowering.

HMS Queen Elizabeth and another aircraft carrier, HMS Prince of Wales, are the largest warships ever constructed for the Royal Navy. The first is due to be launched in 2016. They are being built by the Aircraft Carrier Alliance, a partnership of BAE Systems, Babcock, Thales and the Ministry of Defence.

Captain Simon Petitt, senior naval officer, HMS Queen Elizabeth, said: "This is a very significant moment in the making of the ship, particularly as it's an aircraft carrier, because the guys working in the aft island will be operating and controlling all of the aviation activity on this flight deck.

"It's a massive UK project, it's going to be the most automated and advanced aircraft carrier in the world and it's being built in this country and all of those involved should be rightly proud."

Abandoned plans to switch the type of fighter aircraft used on the Royal Navy’s new carriers will cost taxpayers £74m, according to the National Audit Office.

Defence secretary Philip Hammond last year decided to revert to plans by the former Labour government to acquire the jump jet version of the US-built F-35 Joint Strike Fighter.

Under proposals set out in the 2010 Strategic Defence and Security Review, the coalition had intended to switch to the F-35C carrier variant of the aircraft, even though it meant mothballing one of the two carriers on grounds of affordability.

But the costs of fitting the necessary catapults and arrester gear to the carriers had more than doubled to £2bn.

The National Audit Office (NAO) said although the department acted quickly once it had realised the problems with switching, the decision made in the defence review was based on ‘immature date and flawed assumptions’, and the subsequent work cost about £74m.

Amyas Morse, the head of the NAO, said: ‘It is good that the Ministry of Defence acted promptly, once it became clear that pursuing the option to buy the carrier variant aircraft would cost a lot more money and add another three years to the whole programme.

‘But to achieve value for money in this project, the department will have to manage significant technical and affordability risks, and be consistent in sticking to the present plan.’