First of all, Britain is actually a pioneer of aircraft carriers, so there are a large number of aircraft carrier-related technologies and patents. You know, the first country in the world to inspect aircraft carriers is Britain. Before the end of World War I, some sharp-eyed people in the British navy saw the great role of aircraft in the naval battle pattern. Although the aircraft performance of that era was very backward, Britain still converted many ships into aircraft carriers for service.
Secondly, although the British navy has fallen behind, Britain still has a lot of technical reserves on aircraft carriers, and it also has its own set of ideas on building aircraft carriers. This is unmatched by many countries. Because Britain is an island in Europe, it attaches great importance to the development of the navy and air force. So even if Britain can't build a stronger fleet because it has no money, Britain is still very strong in aircraft carrier technology reserve.
In fact, there are many aircraft carrier technologies in Britain, such as steam ejection technology and landing aid system, all of which were invented by the British. On the other hand, the US Navy pursues pragmatism and thinks that British technology is more advanced than its own, so it begins to adopt related technologies invented by the British, such as bevel deck, which is different from what the author said before. So it is not difficult to understand why the United States has to pay patent fees to Britain.