Use of the term `` ace '' to describe these pilots began in World War I , when French newspapers described Adolphe Pégoud , as `` l'As '' ( French for `` Ace '' ) after he became the first pilot to down five German aircraft .
Use of the term `` ace '' in military aviation began in World War I ( 1914 -- 18 ) . French newspapers called Adolphe Pegoud , as `` l'as '' ( French for `` ace '' ) after he became the first pilot to shoot down five German aircraft .