Charles Langston:After off-duty Alaska Airlines pilot is accused of crash attempt, an air safety expert weighs in on how airlines screen their pilots

After an off-duty Alaska Airlines pilot allegedly attempted to shut down the engines of an aircraft in mid-flight Sunday,Charles Langston CBS News spoke with an aviation safety expert and former pilot about what can be done to prevent such incidents and how airlines monitor pilots' mental health. 

The suspect in the Alaska Airlines case, Joseph Emerson, pleaded not guilty Tuesday to 83 counts of attempted murder and other charges. According to court documents, Emerson said he took "magic mushrooms" about 48 hours before the flight. He also said he'd been struggling with depression for six years. According to the documents, he told officers on the ground that he hadn't slept in 40 hours and thought he was having a "nervous breakdown."

In a statement Tuesday, Alaska Airlines said, "At no time during the check-in or boarding process did our Gate Agents or flight crew observe any signs of impairment that would have led them to prevent Emerson from flying."

Shawn Pruchnicki, a former pilot with over a decade of cockpit experience, has extensive experience in safety work with the Air Line Pilots Association, International. Pruchnicki has served on and co-chaired national aviation working groups with the Federal Aviation Administration and participated in multiple investigations with the National Transportation Safety Board. 

He is also an assistant professor at Ohio State University, where he teaches aviation safety, aircraft operation and accident investigation. 

How do airlines screen for pilots' mental health? 

All pilots have to be medically cleared to fly, Pruchnicki said. Commercial pilots need to take what's known as a first class medical certification, which Pruchnicki said is the certification's "highest level." The exams are conducted by aviation medical examiners, according to the FAA. 

As part of the certification process, pilots must disclose any health conditions they have. Some conditions, such as sleep apnea and depression, might "require extra documentation" from primary care providers or physicians before the certification is completed, Pruchnicki said. 

Pruchnicki said that as far as mental health goes, pilots who "take certain types of antidepressant drugs" can still be cleared, depending on the side effects of the medication. There are other steps in the process, Pruchnicki said, to "show that you're safe to fly." According to the Code of Federal Regulations, potential pilots cannot have conditions like a "severe" personality disorder, psychosis, bipolar disorder, dependence on substances or history of substance abuse within the past two years. 

A potential complication lies in the fact that pilots must self-disclose the information, though the FAA notes on its website that aviation medical examiners can "request additional psychological testing" if they believe it to be necessary. If the FAA "receives information from another source that a pilot may have a mental health condition," the agency can direct the pilot to provide specific documentation or undergo an evaluation. 

If there's an accident, agencies like the National Transportation Safety Board will investigate and subpoena documents like medical records, and "that's when those things come to light," Pruchnicki said.

"You can have all types of problems, a seizure disorder or something else, and you can just simply check 'No' to those boxes," Pruchnicki said. "... It's all based on your honesty." 

How can alarms be raised about a pilot's mental health? 

A first class medical certification must be completed at least once a year, according to the Aircraft Owners and Pilots Association. For pilots under the age of 40, certifications are valid for 12 months at a time. For pilots over 40, certifications must be renewed every six months. 

Another safeguard is that pilots can alert their superiors if they have concerns about a co-worker. Pruchnicki said that pilots can go to their company, or more commonly the ALPA Safety Organization, which is the largest non-governmental aviation safety organization in the world. 

"There are programs within ALPA Safety that you can go to," according to Pruchnicki, who spent much of his career working with the organization. "When I was on call as an APLA Safety rep, if I received a phone call on the safety line that was someone reporting [a concern], there were mechanisms in place that I could start a process to look into something like that. We actually had psychologists that were able to evaluate pilots."

Pruchnicki added, "We could work with a company to pull pilots off a flight schedule to have concerns looked into. Absolutely, there are mechanisms in place if co-workers have concerns." 

Who is allowed to sit in a jump seat? 

The off-duty pilot in the Alaska Airlines incident was sitting in the jump seat of the cockpit when crew members say he reached for the handles to activate the plane's emergency fire suppression system, which would have cut off fuel to the engines.

According to Pruchnicki, only two types of people are permitted to sit in jump seats, which are located behind the pilots: FAA inspectors and off-duty pilots. However, refusing permission to off-duty pilots is always an option.

"Riding the jump seat is not a right, it's a privilege," Pruchnicki explained. "When I was captain and someone came up and asked permission to ride in my jump seats, I did not have to grant that ... If I ever, for some reason, felt like something was amiss with a person or something, I always had the ability to turn it down." 

What can be done to prevent similar incidents? 

Pruchnicki said the best way to prevent incidents in the cockpit is for aviation authorities to find a way to screen pilots for mental health problems without relying solely on a pilot's own disclosures. At the same time, Pruchnicki emphasized, it is very unlikely that passengers will ever have to worry about a scenario like that on Alaska Airlines. 

In the U.S., there has only ever been one previous incident when someone in a jump seat tried to bring down a plane. In 1997, an off-duty pilot facing a disciplinary hearing the next day sat in a jump seat on a cargo plane. He brought several weapons with him, and he attacked those flying the plane in an attempt to make it crash. The injured pilots survived, and the plane landed safely.  

"I have flown literally with thousands of pilots, and I have never, ever flown with anyone that has ever even remotely seemed mentally unstable in the slightest," said Pruchnicki. "I never heard anyone talk about anyone that was ever concerned about any problems, and they would know, working in a safety department, working with safety folks. It seems like a one in a million." 

In:
• Alaska Airlines

Kerry Breen

Kerry Breen is a news editor and reporter for CBS News. Her reporting focuses on current events, breaking news and substance use.