What is the author's perspective in the biography, The Wright Brothers?

The Wright Brothers by David McCullough is told in the third person with author McCullough as the narrator. It is told from several viewpoints. Firstly, it is the story of Orville and Wilbur Wright, two brothers who shared the same dream of man in flight. They weren’t an overnight success; it took ten years of hard work and dedication through many ups and downs, unrelenting criticism and ridicule until they achieved final success.