The British Royal Navy has changed its mind once more and decided to go back to the original design for its two new Queen Elizabeth class aircraft carriers. The new carriers were originally (since 2002) going to have the American F-35B which, like the Harrier, can take off like a helicopter or by rolling down a carrier flight deck. But that has been changed in 2010, for economic reasons, to the F-35C, which operates like the F-18E (no vertical takeoff). The Queen Elizabeths were to have a catapult, like current American carriers do (and pre "ski jump" British carriers did as well). Then it was concluded that the catapult option was more expensive than the original concept and the carrier design reverted to the original F-35B/ski jump model.
These two decisions cost the Royal Navy about $115 million in additional expenses, which is a small part of the cost growth of the two carriers (from $5.8 billion in 2007 to over $8 billion now). The size of the ships has also grown, from 40,000 tons in the first plan (late 1990s), to 58,000 tons when construction started, to 70,000 tons now. There won’t be much more weight increases because the first ship has had its hull largely completed and will leave dry dock next year. Sea trials are planned for 2017 and initial flight operations in 2018. Commissioning is to occur by 2020. Construction on the second carrier (the Prince of Wales) began in 2011. These are the largest warships ever built in Britain and require the efforts of some 10,000 people in 90 companies and 6 shipyards (for building sections of the ships as well as other components).
There are some other problems that required more innovative solutions. For example, in 2011, the Royal Navy retired all its Harrier aircraft and the last aircraft carrier that the Harriers operated from. That presented a problem, as the first of two new carriers won't enter service until the end of the decade. The admirals knew that once the new carrier (Queen Elizabeth) entered service a new generation of pilots would have to be trained to take off and land on a carrier. While the Harriers could land and take off like a helicopter, they often took off (via a "ski jump" flight deck) so they could carry more weight (especially bombs) into action. To deal with this Britain will have four of its naval aviators serve on American aircraft carriers over the next decade, to maintain Royal Navy knowledge of how pilots operate jet aircraft off carriers. The British naval officers will learn to fly F-18s in order to do this. While Britain and the U.S. regularly exchange fighter pilots, this is a special case. The British know from experience that it's easier to train new pilots with experienced Royal Navy carrier pilots. Thus the need to maintain that experience by having British aviators flying F-18s off American carriers until the new British carriers arrive.
The current steam catapult was designed by a British naval officer in the 1950s and were essential for launching the heavier jet aircraft. The British eventually abandoned the large carriers, and steam catapults, because of cost. The high cost of the F-35B led to the order to have the new carriers return to the use of steam catapults. That was scrapped because it would have increased cost of the project by about $3 billion.
Each of these ships will carry normally 34-45 aircraft and helicopters and be able to handle about 110 flight operations every 24 hours (mainly with F-35B). The only weapons will be some 20mm Phalanx anti-missile systems and several 30mm autocannon for use against smaller craft that might threaten the ship. The carriers are highly automated, requiring a crew of only about 1,600 (most of them for air operations). Top speed is 46 kilometers an hour and max aircraft load is 50 fixed-wing and helicopter types.