I am travelling from Washington DC to Copenhagen ( layover 4 hours ) then to Newcastle UK. Do I need a schengen visa? I have a green card and 5 year UK visa and am a citizen of India
As stated in Timatic, the database used by airlines:
Visa required, except for holders of onward tickets transiting on the same calendar day if arriving at and departing from Copenhagen Kastrup (CPH).
So no, you do not need a visa.