Airman

From the Publisher:

Conor Broekhart was born to fly. It is the 1890s, and Conor and his family live on the sovereign Saltee Islands, off the Irish coast. Conor spends his days studying the science of flight with his tutor and exploring the castle with the king's daughter, Princess Isabella. But the boy's idyllic life changes forever the day he discovers a deadly conspiracy against the king.