Report: Germanwings crash co-pilot tested 100-foot descent setting

Updated 5:38 PM EDT, Wed May 6, 2015
SEYNE, FRANCE - MARCH 26:  In this handout image provided by French Interior Ministry, the Rescue workers and gendarmerie continue their search operation near the site of the Germanwings plane crash near the French Alps on March 26, 2015 in La Seyne les Alpes, France. Germanwings flight 4U9525 from Barcelona to Duesseldorf  has crashed in Southern French Alps. All 150 passengers and crew are thought to have died. (Photo by Francis Pellier MI DICOM/Ministere de l'Interieur/Getty Images)
Francis Pellier MI DICOM/Ministere de l'Interieur/Getty Images
SEYNE, FRANCE - MARCH 26: In this handout image provided by French Interior Ministry, the Rescue workers and gendarmerie continue their search operation near the site of the Germanwings plane crash near the French Alps on March 26, 2015 in La Seyne les Alpes, France. Germanwings flight 4U9525 from Barcelona to Duesseldorf has crashed in Southern French Alps. All 150 passengers and crew are thought to have died. (Photo by Francis Pellier MI DICOM/Ministere de l'Interieur/Getty Images)
Now playing
02:04
Report: Prior flight was 'practice' for co-pilot
lead dnt marsh germanwings final moments cell video_00000403.jpg
lead dnt marsh germanwings final moments cell video_00000403.jpg
Now playing
02:00
Reports: Cell phone video shows Germanwings' final moments
nr baldwin brown pruchnicki germanwings descent_00004223.jpg
AP
nr baldwin brown pruchnicki germanwings descent_00004223.jpg
Now playing
01:44
Lubitz sped up descent of Germanwings plane
Caption:FRANKFURT, GERMANY - MARCH 14:(EXCLUSIVE COVERAGE)(EDITOR'S NOTE: This photo is available exclusively through Getty Images except in Germany) In this photo released today, co-pilot of Germanwings flight 4U9525 Andreas Lubitz participates in the Frankfurt City Half-Marathon on March 14, 2010 in Frankfurt, Germany. Lubitz is suspected of having deliberately piloted Germanwings flight 4U 9525 into a mountain in southern France on March 24, 2015 and killing all 150 people on board, including himself, in the worst air disaster in Europe in recent history. (Photo by Getty Images)
Getty Images
Caption:FRANKFURT, GERMANY - MARCH 14:(EXCLUSIVE COVERAGE)(EDITOR'S NOTE: This photo is available exclusively through Getty Images except in Germany) In this photo released today, co-pilot of Germanwings flight 4U9525 Andreas Lubitz participates in the Frankfurt City Half-Marathon on March 14, 2010 in Frankfurt, Germany. Lubitz is suspected of having deliberately piloted Germanwings flight 4U 9525 into a mountain in southern France on March 24, 2015 and killing all 150 people on board, including himself, in the worst air disaster in Europe in recent history. (Photo by Getty Images)
Now playing
03:46
What effects do heavy antidepressants have on patient?
Andreas Lubitz is seen in an image taken from Facebook.
from facebook
Andreas Lubitz is seen in an image taken from Facebook.
Now playing
04:51
How can airlines detect mental problems in pilots?
ac pkg ripley germanwings copilot hometown_00004517.jpg
ac pkg ripley germanwings copilot hometown_00004517.jpg
Now playing
02:53
Germanwings copilot's hometown copes with crash
Caption:FRANKFURT, GERMANY - MARCH 14:(EXCLUSIVE COVERAGE)(EDITOR'S NOTE: This photo is available exclusively through Getty Images except in Germany) In this photo released today, co-pilot of Germanwings flight 4U9525 Andreas Lubitz participates in the Frankfurt City Half-Marathon on March 14, 2010 in Frankfurt, Germany. Lubitz is suspected of having deliberately piloted Germanwings flight 4U 9525 into a mountain in southern France on March 24, 2015 and killing all 150 people on board, including himself, in the worst air disaster in Europe in recent history. (Photo by Getty Images)
Getty Images
Caption:FRANKFURT, GERMANY - MARCH 14:(EXCLUSIVE COVERAGE)(EDITOR'S NOTE: This photo is available exclusively through Getty Images except in Germany) In this photo released today, co-pilot of Germanwings flight 4U9525 Andreas Lubitz participates in the Frankfurt City Half-Marathon on March 14, 2010 in Frankfurt, Germany. Lubitz is suspected of having deliberately piloted Germanwings flight 4U 9525 into a mountain in southern France on March 24, 2015 and killing all 150 people on board, including himself, in the worst air disaster in Europe in recent history. (Photo by Getty Images)
Now playing
04:01
Someone with severe depression 'should not be flying'
nr lklv pleitgen germanwings plane crash lubitz_00004210.jpg
Getty Images
nr lklv pleitgen germanwings plane crash lubitz_00004210.jpg
Now playing
03:10
Should co-pilot's past have disqualified him for work?
A search and rescue worker at the crash site of the Germanwings Airbus A320 that crashed in the French Alps, above the town of Seyne-les-Alpes, southeastern France, 25 March 2015. Search crews resumed helicopter flights around dawn on 25 March to the remote mountainside where Germanwings Flight 4U 9525 from Barcelona to Duesseldorf crashed after a rapid descent, likely killing all 150 people aboard on 24 March.
GUILLAUME HORCAJUELO/EPA/Landov
A search and rescue worker at the crash site of the Germanwings Airbus A320 that crashed in the French Alps, above the town of Seyne-les-Alpes, southeastern France, 25 March 2015. Search crews resumed helicopter flights around dawn on 25 March to the remote mountainside where Germanwings Flight 4U 9525 from Barcelona to Duesseldorf crashed after a rapid descent, likely killing all 150 people aboard on 24 March.
Now playing
02:33
Report: Pilot heard screaming 'open the door!'
A man stands on March 29 2015 in front of a commemorative headstone in Seyne-les-Alpes, the closest accessible site to where a Germanwings Airbus A320 crashed on March 24 in the French Alps, killing all 150 people on board.
JEAN-PIERRE CLATOT/AFP/Getty Images
A man stands on March 29 2015 in front of a commemorative headstone in Seyne-les-Alpes, the closest accessible site to where a Germanwings Airbus A320 crashed on March 24 in the French Alps, killing all 150 people on board.
Now playing
05:37
Should doctor have told pilot's employer of problems?
nr lklv pleitgen germanwings plane crash lubitz_00004210.jpg
Getty Images
nr lklv pleitgen germanwings plane crash lubitz_00004210.jpg
Now playing
01:27
Report: Ex-girlfriend recalls co-pilot's dark side
A stele and flowers laid in memory of the victims are placed in the area where the Germanwings jetliner crashed in the French Alps, in  Le Vernet, France, Friday, March 27, 2015. The crash of Germanwings Flight 9525 into an Alpine mountain, which killed all 150 people aboard, has raised questions about the mental state of the co-pilot. Authorities believe the 27-year-old German deliberately sought to destroy the Airbus A320 as it flew Tuesday from Barcelona to Duesseldorf. (AP Photo/Christophe Ena)
Christophe Ena/AP
A stele and flowers laid in memory of the victims are placed in the area where the Germanwings jetliner crashed in the French Alps, in Le Vernet, France, Friday, March 27, 2015. The crash of Germanwings Flight 9525 into an Alpine mountain, which killed all 150 people aboard, has raised questions about the mental state of the co-pilot. Authorities believe the 27-year-old German deliberately sought to destroy the Airbus A320 as it flew Tuesday from Barcelona to Duesseldorf. (AP Photo/Christophe Ena)
Now playing
01:38
Germanwings pilot identified

Story highlights

Lubitz rehearsed setting the altitude to 100 feet several times on the previous flight, report says

He is accused of deliberately crashing the return Germanwings flight into the French Alps

CNN —  

Germanwings co-pilot Andreas Lubitz rehearsed putting his aircraft into a controlled descent on the flight that preceded the crash of his jetliner into the French Alps on March 24, according to an interim report Wednesday by French air accident investigators.

The report by the French air accident investigation agency, the BEA, is based on analysis of the aircraft’s flight data recorder and cockpit voice recorder.

This indicates that on the flight out from Germany to Spain, “Several altitude selections towards 100 ft were recorded during descent on the flight that preceded the accident flight, while the co-pilot was alone in the cockpit.”

The data recorders indicate the captain had left Lubitz alone on the flight deck for less than five minutes.

On the return flight the same morning from Barcelona, Spain, to Dusseldorf, Germany, Lubitz is accused of purposely slamming Germanwings Flight 9525 into the French Alps, killing all 150 people on board, while the captain was locked out of the cockpit.

The co-pilot refused to let the captain re-enter and failed to respond to repeated contacts from air traffic controllers as the plane made its fatal descent.

Lubitz suffered from bouts of depression and the incident sparked a global debate over how to monitor the mental health of pilots.

Changing altitude settings

The preliminary BEA report details what happened on board the Airbus A320 on both the outbound and return flights. The report and a Germanwings spokesperson both indicate that the same six crew members were on both legs of the trip.

While Lubitz was alone on the flight deck on the outbound flight, he was asked to bring the plane down to a lower altitude.

At one point, “the selected altitude decreased to 100 ft for three seconds and then increased to the maximum value of 49,000 ft and stabilized again at 35,000 ft,” the report said.

Less than two minutes later, “the selected altitude was 100 feet most of the time and changed several times until it stabilized at 25,000 ft.”

At this point the captain buzzed to re-enter the cockpit and the flight continued as planned to Barcelona.

Because he had already been asked to descend, Lubitz’s apparent rehearsal of different altitude settings would have gone unnoticed by air traffic controllers since he did not diverge from the flight plan.

FAA questioned Germanwings pilot’s health

Analyst: ‘It was a dry run’

Asked if there could be any innocent interpretation of the recorded events, CNN aviation analyst Miles O’Brien said, “It was a dry run, there’s no question.”

Despite the wildly different altitude selections, he said, the plane’s altitude was going down at a steady rate, so the captain and air traffic controllers would not have been alerted to what Lubitz was doing.

He was presumably testing the parameters of what the aircraft’s systems would allow, said O’Brien.

“On the Airbus, you have a computer system that tends to overrule what the pilot wants to do if it’s outside the boundaries of acceptability for the aircraft and safety, and so this would be a good way to test where the alarm bells might go off, so you could set the selection for the intent, which of course we all know what happened,” he said.

Lubitz called unfit to work

Violent blows on cockpit door

The report also provides chilling detail of the final minutes in the cockpit on the return flight before the crash.

During the fatal descent, French air traffic controllers called the flight crew 11 times on three different frequencies without any response, it said. The French military defense system also tried three times to contact the aircraft, without any answer.

The 34-year-old captain, who had left the cockpit after the plane reached its cruising altitude of 38,000 feet, buzzed to re-enter the cockpit just over four minutes later.

The cockpit voice recorder then picks up what sounds like knocking on the door half a dozen times, the sound of a muffled voice asking for the door to be opened, and then what sounds like repeated violent blows on the door.

The plane crashes into the mountainside about half a minute later.

CNN’s Lucy Pawle contributed to this report.