Are large planes less loud than small ones?
It depends mostly on the type of engine rather than the size of the airplane. Traditionally, jet engines have always been louder than other types of engines, but that is not true today. High-bypass turbofan engines (a type of jet) are surprisingly quiet. Jet airplanes are louder if they have older engines that make more noise, especially pure turbojet engines that can make a great deal of noise. The worst is military jet engines on supersonic aircraft with the afterburner lit, which are earsplitting in their noise production. These days, though, propellers tend to be major sources of noise. The type of engine driving them is less of a factor than the propeller itself, which can produce a great deal of noise as the blade tips approach the speed of sound at high RPM. Propellers can be very efficient under the right circumstances, but they still aren’t used on large commercial airliners in part because they are just incredibly noisy. Turbofan jet engines essentially have a huge fan in the
