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I learned to fly at San Carlos too (and Palo Alto... West Valley Flying Club).

Take a look at:
http://webtrak.bksv.com/oak

Put in 7/23/2013 and 8:45pm Look for EVA28. It will be a large purple plane coming in from the top left of the screen passing over the center of SFO at 11,000'.

The plane that crashed did the same thing. It pass over SFO at high altitude (common) and then turned cross-wide while rapidly descending. I live in Portola Valley and lived in Palo Alto... You can hear planes doing this because they make a very distinctive whooshing sound as they deploy flaps and decelerate.

EVA28 got to 600' and aborted landing between the San Mateo bridge and Coyote point.

I've heard from a 777 pilot, and this seems plausible to me... that this plane has an automated mode where it will auto-throttle when you're coming in for a landing, allowing you to pitch only and letting the plane handle the throttle.

The problem is on rapid descent, pilots will disengage the auto-throttle. If they fail to re-engage it... they'll pitch up as they're getting too low and expect the auto-throttle to kick in. When it doesn't, there isn't much time to realize it's off and either turn it back on, or throttle back up.

Worse, throttling up in these jets takes a while to kick in.

600'... if the description of the auto-throttle situation is correct... wow, that almost splashed.

Lockheed-Martin released its Silent Sentry passive radar system in 1998 http://servv89pn0aj.sn.sourcedns.com/~gbpprorg/mil/radar/sentry.pdf

And how about http://www.bksv.com/products/environmentmanagementsolutions/airportenvironmentmanagement/skytraksurveillance.aspx
which is a commercial passive radar system specially tailored for replacing an airport's radars.

WTH do you get the idea that Thales are "just starting out"?

First you must measure how many decibel of attenuation you need. For this you need a sound level meter: If you don't have one at hand, a microphone + PC sound card + Audacity can be used as well (many apps for Android/Ipad are also available for this). Measure two sound spectra at your location: the first one with traffic noise present, the second one when you feel that background noise level is comfortable for you. The difference between the two spectra will tell you how much attenuation you need, and which frequencies need to be attenuated more.

Next compare the attenuation offered by each possible solutions (noise attenuationg windows, wall insulation, etc.) against the attenuation you need to achieve. If it isn't enough, move away, otherwise try installing the best solution you can afford.

Noise should be stopped before it enters the walls of your home: Once it is there, it can follow unsuspected paths to reach your ears (pipes, wall joints, etc.). The best way to stop it is to increase the acoustic impedance of external walls and windows.

Attenuation could be increased using viscoelastic materials like rubber: however they are best for attenuating high frequencies.

Also for HATS testing (in fact Apple had advertised positions that required HATS-testing experience).

It's actually pretty difficult to accurately test headphone sound levels because the sound level will depend on the volume of air in the ear canal (for ear buds) or under the cup (for over-ear headphones) as well as the leakage around the head phone. This is dependant on the size of the ear and the pressure of the head band on the head (for over-ear headphones). There's a reason why artificial ears and dummy heads cost thousands of dollars.

Mead Killion (founder of Etymotic Research) gave a talk in Boston recently, and he announced a product similar to what you are proposing, and it should go to market soon. Basically, it's a box that goes between the audio player and the headphones, it measures the voltage of the headphone output, and determines safe and unsafe levels. Rather than measuring SPL levels from the headphones directly, the unit will be factory programed with the output levels from various DAP/headphone combinations (determined using lab measurements) so it can map the voltage to the appropriate level.

[Dr. Killion also gave everyone at the talk a free pair of ER-6's, but that was just icing on the cake :) ]

If the authorities are going to use microphones to determine sound violations, they will be using microphones that meet IEC/ANSI standards for sound measurement equipment. That means mics from companies like Bruel and Kjaer, GRAS, Norsonic, ACO Pacific, Larson Davis, etc.

These mics will definitely measure down to 20 Hz (most "boom car" bass is around 50 or 60 Hz), and some will even get down to 1 Hz.

By the way, classical music generally has much lower bass than hip-hop/r&b/pop/dance music. Seriously.

They likely are talking about dB SPL. Remember, pressure is force divided by area, and pressure is scaler. The headphone speaker diaphragm puts out a force. When you hold the headphone out in the open air, that force is divided by an (effectively) infinite area, and the resulting SPL is very low.

But when you put that speaker diaphragm into your ear, the total interior area of your ear canal is very small. Divide the diaphragm force by the small ear canal area, and you have a large pressure. Voila! High SPL.

Have you ever seen an acoustic calibrator or pistonphone? This is exactly how those devices work. They usually output 94 dB or 114 dB SPL. If you listen to them in the open air, you barely hear the signal, but if you put them against your ear, you could blow an eardrum.