At the same time they needed to pass vertically downward through the entire troposphere—the shell of air surrounding the earth, where weather happened—until the number on the altimeter matched whatever the altitude of Waco was. Again there were known procedures for achieving that, all of which needed to mesh with the series of turns dictated by those harried Texan air traffic controllers. The operation of the jet’s controls toward the systematic achievement of those objectives, the terse, pithy, but utterly calm exchanges with Johan and with the voices on the radio, all combined to put her into a state of being that the Dutch referred to as normal with the accent on the second syllable. A different thing altogether from the English "NORMal."