Here's everything we know about the the crash of Germanwings flight 9525

Germanwings flight 9525 flying from Barcelona, Spain to Düsseldorf, Germany, crashed in the Alps on Tuesday morning near the town of Seyne-les-Alps, France. All 150 passengers and crew on board the airliner were killed. French authorities point to the apparently intentional downing of the flight by its 28 year-old co-pilot Andreas Lubitz as the most likely cause of the crash.

Here's everything we know about the crash of Germanwings flight 9525:

• Founded in 2002, Germanwings is a low-cost subsidiary of Germany's Lufthansa.
• The Airbus A320 - registration number D-AIPX - was delivered to Lufthansa on June 2, 1991.
• D-AIPX joined the Germanwings fleet in 2014
• According to a statement from Airbus, the Germanwings jet had accumulated 58,300 flight hours on 46,700 flights and was powered by a pair of General Electric/SNECMA CFM-56 5A1 turbofan engines.
• The Airbus had received maintenance attention in Düsseldorf the day before the crash.
• According to the airline, the jet took off with a clean bill of health.

• Weather conditions during the flight were clear.
• The plane dropped to a cruising altitude of just 5,000 feet from 38,000 feet in about 8 minutes.
• Contact between the airplane and French radar and flight controllers was lost at 10:53 a.m. local time at an altitude of about 6,000 feet.
• A witness nearby told the Associated Press, "The noise I heard was long - like 8 seconds - as if the plane was going more slowly than a military plane speed. There was another long noise after about 30 seconds."

• 150 passengers and crew were killed in the crash; 72 onboard were from Germany and between 35-49 from Spain.
• This includes 16 students and two teachers from a small town in Germany.
• Three Americans were also on the ill-fated flight - including a mother and her adult daughter from Virginia.
• The Airbus' cockpit voice recorder, one of the two "black boxes" on board the jet has been recovered.
• Although damaged, investigators were able to retrieve data from the recorder.
• Only the outer casing of the Airbus' second "black box," - the flight data recorder - has been found.
• The memory card containing the recorded information from the FDR became separated from its casing by the crash and was still missing.

• According to the lead prosecutor in the investigation, about 30 minutes into the flight, co-pilot Lubitz locked the captain out of the cockpit after the captain left the flight deck.
• Lubitz then put the jet into a steep, unapproved dive by instructing the Airbus' autopilot system to descend to just 100 feet.
• The captain reportedly made numerous attempts to regain entry but, according to investigators, the co-pilot made no attempt to answer the requests.
• The captain even, reportedly, used an ax to try to break down the door.

• Prosecutors said Lubitz did not make any distress calls during the 8-minute-long descent, nor did he answer any of the distress calls made be air traffic control.
• During the descent, the co-pilot's breathing remained normal.
• Lubitz joined Germanwings in September, 2013 after graduating from Lufthansa's flight training school. He had just 630 hours of experience at the time of the crash.
• According to Lufthansa CEO Carsten Spohr, Lubitz took a months-long leave of absence from training at one point. Due to Germany's medical privacy laws, the reason for the hiatus is unknown.
• A source familiar with the investigation told the Wall Street Journal that Lubitz was in treatment for depression, but hid the treatment from his employers at Lufthansa.

• The source also told the Journal that there is no evidence to suggest the co-pilot was taking any "mind-altering medications" at the time of the incident.
• Earlier on Friday, prosecutors said a doctor's note stating that Lubitz was unfit to fly on the day of the crash was found at the co-pilot's residence in Düsseldorf, Germany.
• According to the Wall Street Journal, that note is reportedly from the pilot's psychiatrist.
• A second note was also found in pieces at the residence, but its contents are unclear.
• In a statement, Germanwings said Lubitz had not submitted any of the notes to the airline.
• Lubitz apparently ignored his doctor's advice and reported for duty as scheduled.