Normalization of deviance

Recently, I became aware of an analysis of the Gulfstream IV crash last year in Bedford, MA (KBED), an airport where I train.

To recall, the crew attempted to takeoff with the gust lock* engaged – the plane was never airborne and crashed after overrunning the runway. All aboard died.

*gust lock is a device which prevents the control surfaces from moving to protect them on the ground from wind gusts. It is supposed to be disengaged before flight.

Besides not disengaging the gust lock, the pilots failed to perform a flight control check (that verifies that controls move in all directions that they should). This check is standard for any plane and if performed would have alerted the crew to the problem.

But the astounding revelation in the NTSB report is that the flight crew almost never performed checklists: “A review of data from the airplane’s quick access recorder revealed that the pilots had neglected to perform complete flight control checks before 98% of their previous 175 takeoffs in the airplane, indicating that this oversight was habitual and not an anomaly.”

This has been referred to as normalization of deviance and is explained here. That is, deviant behavior is so commonplace that it is no longer considered deviant. And yes, it happens in healthcare too.

For those who want more details, the NTSB report is here.