The Spad XIII was one of the better fighters in WW1, built from a French design, packing Vickers guns and up to 200 horsepower. After 1917, German fighters began to catch up, but it was still in production at the end of the war.
The Spad held it togther in a dive, something it's predecessor Nieuport couldn't do, shedding it's upper wing from time to time. Eventually every French front line squadron was equipped with these planes. They were also used by the Royal Air Force's No. 23 Squadron, and the Americans. There were plenty of notable pilots, including Georges Guynemer, Rene Fonck and even Eddie Rickenbacker.
You can see one of these planes if you visit the States, at the National Museum of the US Air Force in Dayton, Ohio. However, if you can't make it, you can sit in one (although virtually) on the Museum's web site. Early aircraft are mesmerizing, as nothing is hidden, and you can see how some things evolved by comparing them to modern aircraft. It's also amazing how well built they were, and how early on they figured out how to make something sturdy and light at the same time. It's also refreshing not to see plastic anywhere.