Originally Posted by jrl22

care to elaborate?

are you talking about the EPNDb (Effective Perceived Noise Decibel) footprint? while now much less of an issue than 30 years ago, community noise restrictions still influence airport operations -- which runways can be used, types of aircraft that can land or take off, etc -- during certain hours (I'm familiar with SNA, SAN, DCA; doubtless there are others); takeoff footprints and approach footprints are different; both are functions of weight, engine thrust setting, flap setting, etc; both require a lot of test data to determine; each airplane/engine combination is certified separately ... see http://www.boeing.com/commercial/noi...NoiseIndex.pdf for some interesting data

if you're talking about interior noise, that's much more subjective, and obviously depends on where one is seated in the cabin ... yes there are some design (amount of insulation between the skin and sidewalls, for instance) and manufacturing (finish quality of joints between skin panels, windows/frames, etc) influences, but the interiors are all buyer-furnished equipment, and the different materials used in seats, carpets, cabin dividers etc all have slightly different sound-absorbing properties