The movie is about the American volunteers who joined the French air corps because they wanted the adventure and wanted to learn to fly. Some of them fought for several months before the USA entered the war.
The German government protested the term "American" in the official name of the organization, so it was changed to Lafayette (actually pronounced La-feet), in honor of the French nobleman who fought for Washington and the Americans during their Revolution.
There was one initial squadron that had Americans, but actually most of the American volunteers were spread out across the air corps.
The Squadron it is based on flew Nieuport 11s for a few months before receiving S.P.A.D. 7s, which they continued to fly until the end of the war. They were mustered into the American Aircorps once the U.S. was fully involved, not unlike the Flying Tigers during WWII.
The planes depicted in the film are Nieuport 17s and the do not even get Lewis guns mounted on their top wing. This is probably due to limitations in their computer program that ran all the CG dogfights.
They are seen fighting whole flights of Red Fokker Dr.1s. Of course Richthofen was famous for his red triplane (even if he only flew a tri in the last months he fought) and many people feel it is a particularly poor choice since everyone is going to say “there was only one Red Baron, not whole squadrons of them!”
But there was one German group that did fly red triplanes. However, I doubt the film makers even knew that.
It obvious to me that having all the German planes be one type and one color and all the French planes being one type and one color is all due to the limitations of the CG programming.
But at least we will see Nieu 17s and Fokker Dr.1s in great 3-D fighting scenes.
Even the Red Baron movie has a plot that sounds ridiculous. He is in love with “nurse Katey”, who apparently does not even have a last name. Because of her and seeing his friends die he realizes the futility of war too late. Sniff, sniff.
Actually, by all accounts he LOVED it and wanted to kill as often and as many people as he could, preferring the classic “dive by shooting”, aiming directly at the pilot from as close as he could get and firing so he killed without his victim having any chance to react.