Singapore Airlines plane dropped 178ft in five seconds, black box data reveals BBC.comSingapore Airlines flight that hit deadly turbulence fell 178 feet in 4.6 seconds Fox BusinessWhat causes turbulence on flights and which routes around the world are most affected? The GuardianGravitational changes, 178-feet drop caused injuries on Singapore Airlines jet that hit turbulence The Associated PressTurbulence-hit Singapore Airlines flight fell 54 meters in less than five seconds, investigation finds CNBC