Reply #18: GREAT rebuttal!

[Sweet Pea]

I stand....er....sit chagrined.

Did you look up doppler effect with regards to sound waves? I'm sorry, but here at work I can't check to see if there is a You Tube video to help you out.

But in any event, could you describe what the doorman *should* have heard, keeping in mind the direction the aircraft was coming, the altitude, the physics of sound propagation in ambient air and what was *inbetween* him and the aircraft?

And yes, when in front of jet engines, what you hear for the most part are the turbines and stator blades spinning, which is remarkably quieter than hearing it from the rear where the exhaust makes serious noise.