Washington CNN  — 

Years before Andreas Lubitz crashed a commercial airliner into the French Alps, the Federal Aviation Administration raised questions about his mental health, declining to give him a medical certificate.

The agency switched course about three weeks later in 2010 after a physician working with Lubitz said his treatment was complete.

That and other findings are revealed in documents obtained by CNN through a public records request that cover a time frame between April 2008 and July 2010 – the period in which Lubitz was in Arizona training to be a pilot for Lufthansa, which owns Germanwings. Lubitz is accused of purposely slamming a Germanwings jetliner into the French Alps on March 24, killing all 150 people on board. He suffered from bouts of depression and the incident sparked a global debate over how to properly monitor the mental health of pilots.

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According to the documents, Lubitz suffered from “reactive depression,” which the medical examiner said was caused by “modified living conditions” and “decompensation subsequent to excessive demands.” Reactive depression can resolve itself when the individual recovers from an overwhelming event, according to Jacqueline Brunetti, who works as a medical examiner for commercial pilots.

From January through October 2009, Lubitz received psychotherapeutic treatment, which included two medications for depression – Cipralexone and Mirtazapine, both anti-depressants.

“The use of 2 drugs would suggest that maybe a single drug was not sufficiently effective,” said Burnetti, who did not treat Lubitz, but said pairing anti-depressants could indicate an inability to “cope with either day to day work and/or home demands.’”

It is not entirely clear when his depression began. But a document from April 2008 identifies Lubitz as medically fit to fly. Lufthansa CEO Carsten Sphor told reporters after the crash that Lubitz interrupted his training at some point in 2009. That break lasted several months. Medical documents do not reference that break or reveal why he took it.

But it is clear from the documents that once treatment for his reactive depression was complete in October 2009, Lubitz applied to have his medical certificate and student pilot certificate renewed.

Then, there is something of a mystery.

On a June 14, 2010 questionnaire for a medical and student pilot certificate, Lubitz checked “no” when asked whether he presently or in the past experienced “mental disorders of any sort; depression, anxiety, etc.”

There is another copy of the same questionnaire with the same June 14, 2010 date. But on this form, Lubitz checked “yes.” That second document indicated that the medical examiner modified the questionnaire to reflect Lubitz suffered from “reactive depression” from November 2008 through July 2009.

Contacted by CNN, the FAA couldn’t definitively explain the existence of the two questionnaires.

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“The questionnaire is done electronically,” said Laura Brown, a spokesperson for the FAA. “In some cases an airman may fill out the first page of the questionnaire before visiting with the doctor and once the doctor’s visit is complete the form is updated,” she said.

She added that even after it’s updated, the original form “still lives in the system.”

When asked if they were aware of the existence of two conflicting medical documents, Germanwings Senior Vice President of Communications Joachim Shöttes said “no” and that they were “unaware” if both of the documents were submitted to the airline.

“I want to point out that the (First Officer) had been medically cleared to fly and hold all the requisite licenses,” he said.

Lubitz had not always been cleared to fly, however.

A July 8, 2010 letter from the FAA’s Aerospace Medical Certification Division informed Lubitz that after reviewing his medical examination results the FAA was “unable to establish your eligibility to hold an airman medical certificate” due to his history of “reactive depression.”

Dr. Warren Silberman, who prepares FAA medical certifications, signed that letter and requested a detailed medical status report from Lubitz’ prescribing physician detailing “when medication(s) were discontinued and confirmation of no reoccurrence of the symptoms since discontinuing medication(s).”

In the letter, Silberman also requested “a diagnosis, prognosis with medication(s) and follow-up plan” before consideration of reinstating Lubitz medical certificate and student pilot certificate.

The tortuous trail to ‘Why?’

In order to fly again, Lubitz would need his physician to vouch that he had successfully been treated and was no longer suffering from reactive depression.

Lubitz’ medical records show the medical specialist treating him wrote two letters saying Lubitz had successfully completed treatment. One was addressed to Lubitz and the other to an airline medical examiner, although the name of that person was redacted.

That letter to the airline official states “considerable remission has been obtained” and “medication has been tapered.” It described Lubitz as being “without memory disorders and phobias” and “mentally stable.”

After he was cleared by his psychotherapist, the FAA sent a new letter to Lubitz stating he was cleared to fly. That letter was also signed Silberman and it included that precautions must be taken in order for Lubitz to fly.

“You are cautioned to abide by Title 14 of the Code of Federal Regulations (CFR’s), Section 61.53, relating to physical deficiency. Because of your history of reactive depression, operation of aircraft is prohibited at any time new symptoms or adverse changes occur or any time medication and/or treatment is required,” Silberman wrote.

But Silberman says this is nothing more than a self-monitoring system.

“You don’t see the airman with the number of cases so you have to rely on how good the letter is,” he said.

In other words, FAA certifiers don’t see the actual airman. CNN was unable to reach Jörg Siedenburg, the aviation medical examiner listed in the documents as the physician Lubitz visited for clearance to fly.

But the decision to approve or deny a pilot who was once deemed ineligible to fly is based on doctors’ letters, Silberman said. And in his opinion, the letter Lubitz’ physician provided “was a very complete and legit letter.”

Silberman added: I “had no reason to question its accuracy.”

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