Single-pilot operations and lemon juice

Psychology researchers have found that some of the dumbest criminals and the cockiest pilots may have something in common: a hazardous cognitive bias, the Dunning–Kruger effect that hinders self-perception, clouds judgment and leads individuals to overestimate their ability. However, new psychological discoveries may provide a cure.

For the criminal, an overly optimistic assessment of the skills required to rob a bank may send them directly to jail, whereas a pilot with a false assessment of their abilities may take-off into a thunderstorm, continue to fly into degraded visual conditions, or attempt a hazardous circling manoeuvre that leads to a fatal accident.

Research into the Dunning–Kruger effect began following an attempted bank robbery that involved a unique element, lemon juice. In April 1995, McArthur Wheeler robbed two Pittsburgh banks in broad daylight without a mask. Security cameras provided good images of his five-foot-six, 270-pound (122 Kg) body and his face. Within hours of posting images on the local news, the police had a tip and he was taken into custody.

Bank robber Wheeler, a resident of a Pittsburgh suburb made an odd confession to detectives, exclaiming, “But I wore the juice.” Confused, the detectives pressed Wheeler on what he meant. The suspect stated that he knew lemon juice was an ingredient in invisible ink, thus he thought ‘logically’ that if he covered his face in lemon juice, then his face would be invisible to the security cameras. Other than his eyes burning from the juice, Wheeler was convinced that his plan would work. He was incredibly mistaken, promptly convicted and later featured in the 1996 World Almanac as the world’s dumbest criminal.