> I particularly enjoyed Sam's report on small airplane and their associated noises.

If you ever fly on an Airbus A320, don't worry if - just before takeoff - you get the impression that under your seat there's a barking dog (or a growling lion, in hotter weather).

As far as small planes (like Cessna 172s and such) are concerned, their noise level is so peculiar and characteristic that everyone of the C172M at my flight school has his "particular" engine/flap motor/structural noise.