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Created May 6, 2011 20:16
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In December 1995, American Airlines Flight 965 departed from Miami on a regularly scheduled trip to Cali, Columbia. On the landing approach, the pilot of the 757 needed to select the next radio-navigation fix, named "ROZO." He entered an "R" into his navigation computer. The computer returned a list of nearby navigation fixes starting with "R," and the pilot selected the first of these, whose latitude and longitude appeared to be correct. Unfortunately, instead of "ROZO," the pilot selected "ROMEO," 132 miles to the northeast. The jet was southbound, descending into a valley that runs north–south, and any lateral deviation was dangerous. Following indications on the flight computer, the pilot began an easterly turn and slammed into a granite peak at 10,000 feet. One hundred and fifty-two passengers and all eight crewmembers aboard perished. Four passengers survived with serious injuries. The National Transportation Safety Board investigated, and—as usual—declared the problem human error. The navigational aid the pilot was following was valid, but not for the landing procedure at Cali. In the literal definition of the phrase, this was indeed human error, because the pilot selected the wrong fix. However, in the larger picture, it wasn't the pilot's fault at all.
The front panel of the airplane's navigation computer showed the currently selected navigation fix and a course-deviation indicator. When the plane is on course, the needle is centered, but the needle gives no indication whatsoever about the correctness of the selected radio beacon. The gauge looks pretty much the same just before landing as it does just before crashing. The computer told the pilot he was tracking precisely to the beacon he had selected. Unfortunately, it neglected to tell him the beacon he selected was a fatal choice.
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