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Normalization of Deviance

Posted 3 years 153 days ago ago by Admin

What can the helicopter world learn from NASA’s mistakes?  I’m specifically talking about the Challenger disaster and the cancer of “normalization of deviance” that was the root cause of that tragedy.

On November 3, 2014, NASA Chief of Safety and Mission Assurance Terry Wilcutt and Deputy Chief of Safety and Mission Assurance Hal Bell, put together a presentation entitled “The Cost of Silence: Normalization of Deviance and Groupthink.” 

The term was coined by Diane Vaughan, professor at Columbia University's Department of Sociology, in her in-depth study of the Challenger disaster.  She defines normalization of deviance as: “The social phenomenon that people within the organization become so much accustomed to a deviant behavior that they don't consider it as deviant, despite the fact that they far exceed their own rules for the elementary safety. To people outside of the organization, the activities seem deviant; however, people within the organization do not recognize the deviance because it is seen as a normal occurrence. In hindsight, people within the organization realize that their seemingly normal behavior was deviant.”

Vaughn developed her theory of the normalization of deviance in her book The Challenger Launch Decision. She details how, during the developmental phase of the Space Shuttle Program, the normalization of deviance resulted in a dangerous design flaw in the design of the spacecraft. The group assessing the joints on the solid rocket boosters conducted analysis to find the limits and capabilities of joint performance. Each time, evidence initially interpreted as a deviation from expected performance was reinterpreted as within the bounds of acceptable risk. The acceptance of this risk led to Challenger exploding on the morning of January 28, 1986. 

Humans have a tendency to rationalize shortcuts under pressure, especially when nothing bad happens. The lack of bad outcomes can reinforce the rightness of trusting past success instead of objectively assessing risk. Think about the five people who lost their lives strapped into the FlyNYON helicopter with known unsafe and unapproved safety harnesses.

Pilots who have accumulated years of experience and a strong sense of confidence are at risk of normalizing deviance unless they have sufficient oversight and a strong peer group. The crash of Gulfstream G-IV N121JM on May 31, 2014, is a case in point.

The pilots started the engines without using the engine start checklist and neglected one of the steps, which would have them disengage the flight control gust lock. They then skipped the engine-after-start checklist, which called for the flight controls to be checked. Had they done this, they would have realized the flight controls were locked. They also skipped both the taxi and lineup checklists, as well as the requirement to check the elevator's freedom of movement at 60 knots. With the gust lock in place, they were unable to set takeoff thrust and realized this, but still continued the takeoff never reaching the target thrust setting.

The aviation community could not understand how two pilots had been so inept. The answers were in the aircraft’s quality assurance recorder.  What was learned was this type of behavior was the norm for them. The recorder revealed that they had skipped the flight control check on 98% of their previous 175 takeoffs.

These two pilots didn’t fly in a vacuum, as they occasionally flew with contract pilots who witnessed their habitual procedural non-compliance. By tolerating their deviance, the contract crews became enablers serving to reinforce the behavior as normal.

An article in aviationchief.com, “Avoiding and Curing the Normalization of Deviance for Pilots,” stated:

At each stage of a new pilot's growth comes a time where he or she is tempted to think, "At last I know what I need to know." Some pilots may even arrive at the "At last I know everything there is to know" stage. With each new level of license and training the concept of "You Don't Know What You Don't Know" should become reinforced. The new pilot, if not careful, may end up in the "deviant pilot" class without having ever accomplished any level of expertise.
A new pilot who does not continue his or her education is at risk of stagnating into comfortable routines that do not take advantage of lessons learned by others. Poor training can be even worse than no training if you are being taught the wrong things. In either case, the pilot becomes too embarrassed to expose him or herself to further training. This is an easy trap to fall into when flying as an amateur because there is little or not oversight, outside of a biennial review. When exposed to SOPs, these pilots are likely to react negatively. "I've been doing fine without them!"

The article argues that an expert’s path to deviance is different from a new pilot because the expert should know better. 

With each pilot there are likely to be a combination of issues leading toward the normalization of deviance. These issues form a disease, which impacts the pilot's professional health.

Pilots risk professional stagnation when they feel they have ‘Seen and done that,’ which can serve to weaken motivation to revisit the books or keep up with the latest techniques and procedures. The best way to cure pilot stagnation is to always have a goal in sight. Even those pilots without the next rating or helicopter type on the horizon can motivate themselves to mentor the next generation of pilots.

            With experience comes confidence but that may often lead to over-confidence. It’s important to realize that even the best pilots make mistakes, a fact supported in accident investigations. Those pilots did not set out to crash their aircraft, but they were met by circumstances that you may one day have to confront. It’s important to realize that your actions set the tone for others. Less experienced pilots may be tempted to mimic your actions without the same base of experience to fall back on. 

An individual is unlikely to realize he or she has been infected by deviant, unsafe behavior because it’s become normal.  So ask yourself, “Is there any normalization of deviance occurring in my organization?”  

If so, identify it, and then cut it out for the deadly cancer it is. 

About Randy:
Randy Mains is an author, public speaker, and a CRM/AMRM consultant who works in the helicopter industry after a long career of aviation adventure. He currently serves as chief CRM/AMRM instructor for Oregon Aero. He may be contacted at [email protected].