Investigators said co-pilot Andreas Lubitz, suspected of deliberately crashing a plane in the French Alps in March, practiced entering the fatal descent settings the same day as the crash.
More details have been emerging in the German press about Andreas Lubitz and the circumstances of the crash.
Investigators found the note when they searched Lubitz's flat.
Andreas Lubitz reportedly spent 18 months receiving psychiatric treatment during pilot training for German airline Lufthansa.
French prosecutors offered no motive for why the young German co-pilot crashed his plane.
A fake article gaining traction on the web claims the aviation authority praised pilot in a 2013 article.
Germanwings co-pilot Andreas Lubitz, who lived with his parents in a small town, had 600 hours of flight experience.