Andreas Lubitz modified the automatic pilot system several times to increase the speed of descent.
"the pilot in the cockpit used the automatic pilot to put the airplane on a descent towards an altitude of 100ft (30m)"
"Then several times the pilot modified the automatic pilot settings to increase the speed of the airplane as it descended," it added.
Germanwings also said it was unaware that Lubitz, 27, had experienced depression while he was training to be a pilot.
Lufthansa confirmed on Tuesday that it knew six years ago that the co-pilot had suffered from an episode of "severe depression'' before he finished his flight training.
"We didn't know this,'' said Vanessa Torres, a spokeswoman for Lufthansa subsidiary Germanwings, which hired Lubitz in September 2013.
From (and more at):-
Germanwings crash: Co-pilot Lubitz 'accelerated descent' - BBC News