How does EASA affect Norway which is not part of the EU?
That depends entirely on the Norwegian government - like Switzerland, they can pick and choose which parts of EU legislation they wish to enact. The UK, on the other hand, has ceded total control of aviation legislation and, consequently, is powerless to influence EASA. As the farming and fishing industries have found before, the UK parliament is completely incapable of protecting UK interests from the excesses of the EU.