So I will be in Dublin in May on a cheap Delta ticket from the recent Delta/United fare war spat. My plan was to continue on from Dublin to Sarajevo to visit a friend who is working there. Unfortunately she can not guarantee right now that she will be there due to work travel. So I am trying to make some back up plans. I was looking at where RyanAir flies and there are pretty cheap flights under $50 round trip to to Glasgow as long as I don't have to check a bag. My new carry on backpack is 1" too deep to be a legal RyanAir carry on. Because it is a backpack if I don't fill it full and I can squish it into the bag sizer will I be ok? I know there are horror stories about carry ons and RyanAir and I don't want to have to pay the sizable fee if I get "caught".