This is a five-part series on Active Noise Reduction in General Aviation. It came about because hundreds and hundreds of you have been asking good questions about ANR technology and its advantages in airplanes. This series is intended to provide G.A. pilots with a fairly technical and thorough understanding of this technology and the important criteria that will affect performance and long term satisfaction While not exhaustive, you should "graduate" with a clear picture of the role active cancellation can have on your flying safety, comfort and overall enjoyment.

Here is the structure of this five-part series of articles:

• Section 1: The Basics of ANR...a review of how active noise reduction works and the design variables involved; why it's so difficult to design a really effective ANR headset, even though the basic principles of ANR are rather simple.
   
• Section 2:  Acoustic Issues...how to measure, understand and compare the manufacturer's performance figures and noise cancellation curves...and why some of the figures you see in headset ads are meaningless.
   
• Section 3: Airplane Issues...the nature of the noise spectrum we're trying to cancel, and the importance of good low-frequency attenuation.
   
• Section 4: Ergonomic and Interface Issues...what's involved in the design of a headset that we don't mind wearing for many hours!
   
• Section 5: Optimizing Your Flying Experience...how noise impacts your health, safety and competence as a pilot, and why active cancellation makes flying a "better" experience.

With that introduction, let's get started...

LightSPEED Technologies, Inc.
15812 SW Upper Boones Ferry Road
Lake Oswego, Oregon 97035 USA