 Years of protracted legal conflict ensued with many other aircraft builders until the U.S. entered World War I, when the government imposed a legislated agreement among the parties which resulted in royalty payments of 1% to the Wrights.There are still conflicting claims today over who first invented the aileron.Other 19th century engineers and scientists, including Charles Renard, Alphonse Pénaud, and Louis Mouillard, had described similar flight control surfaces.