I'm not going to beat around the bush here, this is for a school assignment (not on this topic but rather our knowledge of ArcGIS and applying it to a problem of our choice). I'm trying to map sound contours of aircraft engines (I've been graciously allowed to use just the approach noise level so no need to worry about full power, flyby, fly over etc.).

How do I apply an anisotropic buffer to a map? I have the shape files and everything I just need to use the right tool and method (which I can't seem to find, but it's in the ArcGIS documentation that it's possible to apply anisotropic buffers as opposed to standard isotropic buffers, I will be searching google some more on how to apply an anisotropic buffer but I thought I might as well post here just in case anyone reading this knows how to do it).

Also, if anyone knows the right equation to use for sound intensity decay over distance (or do I want to use sound pressure here?) I would really appreciate that. I've also been graciously allowed to use set distances (ie. 100m, 200m, 400m, 800m etc.) again because this isn't a physics course or anything rather a course on learning how to use ArcGIS, but I want to figure out how many people in the residential zones would be affected by say something like 60 or 70 EPNdB from aircraft rather than "at 3200m these people will be affected by x EPNdB of sound". So far I know that sound decay is approximately -6dB if you double the distance but I'd really like a formula so that I can calculate where the aircraft noise is a concern for residents for different types of aircraft (ie. Passenger jets, bizjets, and private aircraft). That is, given x dB of sound at the "source" (100m away) and a wanted value of x dB I want to figure out what distance the wanted value will occur at (as well as the anisotropic equation perferably).
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 GISX-R (13 items)
CPUMotherboardGraphicsRAM
i7 920 D0 ASUS P6TD Deluxe XFX HD6870 1GB Corsair 6GB DDR3-1600 (9-9-9-24)
Hard DriveOptical DriveOSKeyboard
Crucial M4 64GB LG 24X SATA DVD-RW Windows 7 Ultimate Logitech G15
PowerCaseMouse
620W Antec High Current Gamer Lian Li K58W MS OEM