From Ars Technica
Unmanned aircraft crash. In fact, they crash a lot—though there's no recent specific data, the Congressional Research Service reported last year that despite improvements "the accident rate for unmanned aircraft is still far above that of manned aircraft." And while many of those accidents can be attributed to hostile fire or terrible flight conditions, a significant percentage of drone crashes is caused by human error. A December 2004 Federal Aviation Administration (FAA) study of Defense Department drone crashes found human factors to be a causal factor in about a third of the cases the researchers examined.
But as four human factors engineering researchers have found, sometimes the accidents are by design. That is, the design of the systems that operators use to fly the drones are so bad that they invite accidents. A recent Ergonomics in Design article reported that a small but significant number of crashes could be directly attributed to bad ergonomics on ground control station hardware. These factors may have played a major part in crashes that were attributed to other causes.
Take, for example, one drone crash in 2006. As the operator brought the drone in for a landing, he meant to flip the landing gear button on the control joystick but accidentally hit the nearby ignition switch instead—shutting off the engine in mid-flight. The $1.5 million drone plummeted to the ground, a total loss. On another occasion, glare on a screen was so bad that a drone operator couldn't read an alert and mistook it for a landing signal—again killing the engines before the drone had landed.
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