We do aerodynamics and structures rather well...and we are pretty good at R n D and avionic development ...so far so good.....but we never built aircraft with one rather essential detail..well a couple actually..in mind....maintainability and accessability...why struggle for 3 hrs to remove / refit a component when, with a bit of design, the time can be reduced considerably....as Mr Boeing showed.
A few weeks ago, I met some very nice and very clever people from Loughborough...and let them take a few spare parts of a dead aircraft...they had never done this before despite being well qualified in their fields...at the end of the day, one opined that, " we don't build aircraft for ease of access do we"...and freely admitted they had no idea as to how a design, which looks superb on CAD etc..could be a nightmare when fitted.
Then there were the production techniques / processes which hardly helped matters.
In short, the good old British class culture served to hasten the demise, sadly, of the UK aviation sector.