But if you try sometimes... Fighter aircraft became much better during the Second World War.  But, apart from the development of engines, it was not a straightforward matter of monotonous improvement.  Aircraft are a series of compromises.  Improving one aspect of performance almost always compromises others.  So, for aircraft designers in World War Two, the question was not so much "what will we do to make this aircraft better?" but "what are we willing to sacrifice?"   To explain w