Quieter, cleaner airplane landings on the way | Science Blog

Quieter, cleaner airplane landings on the way | Science Blog: "The new procedure, called a continuous descent approach or CDA, keeps aircraft at cruise altitude until they are relatively close to an airport. At this point, the aircraft make an even, continuous descent to the runway. The result is an average noise reduction of four to six decibels. A three-decibel difference is appreciably noticeable to the human ear while a 10-decibel reduction equates to 50 percent less noise. Side benefits include reduced fuel burn and emissions, and slightly shorter flights, as aircraft operate at lower power settings, stay at higher altitudes, maintain higher speeds, and take more direct--and thus shorter--paths to the runway."