Carl Eisen, 60, vividly remembers his first panic attack: Sept. 11, 2001. He was at Home Depot buying a new pump for his homes water well when he heard that a plane had hit the World Trade Center.

Immediately, the pilots thoughts turned to his wife and son, who was 9 months old at the time. He dropped to the floor of the aisle, hyperventilating. It felt like an elephant was sitting on my chest.

He didnt fully comprehend at the time that he was experiencing a panic attack. Once he caught his breath, Eisen stood up and walked out of the store.

You would think that a person having a panic attack would seek help from a therapist, but I didnt, said Eisen, who flew for a major commercial airline at the time but requested his former employer be kept confidential.

It wasnt until much later that he recognized that incident for what it was. Hed always thought his anxiety was normal, and when he developed symptoms of depression, he tried to manage them on his own. During the years following Sept. 11, however, his symptoms of depression and anxiety worsened. He finally realized he needed help.

But getting help for mental health could also threaten his career. Seeing a therapist or psychiatrist under company insurance requires a diagnosis, Eisen said. And pilots must report any mental health diagnosis to the Federal Aviation Administration (FAA).

In a recent interview, Eisen pulled out a copy of his FAA first-class medical , which is the medical clearance form required for both commercial and cargo pilots. Pilots must be in peak health to earn that clearance, both mentally and physically. He read aloud from the document listing potentially disqualifying health issues like heart problems, neurological disorders, diabetes and substance dependence.

One particular question stood out: Answer yes or no. Mental disorders of any sort: depression, anxiety, etc.?

What happens if I say yes to that? Eisen asked. Im grounded.

The FAA has strict rules about the mental health of pilots, prohibiting those with severe personality disorder, psychosis and bipolar disorder from flying. Even fairly common concerns like anxiety and depression can put them off the job, which keeps many pilots like Eisen from seeking help.

Little data exists on pilot mental health, most likely because of the stigmatization and fear of the repercussions, Eisen said. A 2016 Harvard University survey found that 12.6% of the 1,848 airline pilots who completed the survey were clinically depressed, and 4% reported having suicidal thoughts within the past two weeks. While there is little data available, anecdotal evidence suggests that the pandemic and its toll on the airline industry has only furthered job stress.