Jet engines and more specifically the gas turbine jet engines employed in most aircraft are notorious for their excessive noise level whether in aircraft or in industry or on ships.

The noise pollution can be uncomfortable and possibly even dangerous to humans. As a result there are a variety of government regulations imposed requiring aircraft to adhere to certain maximum noise levels and limit the number of takeoff and landings of certain aircraft based on their level of overall noise output.

In the mid 1980's the International Civil Aviation Organization (ICAO) established the Committee on Aviation Environmental Protection (CAEP) which developed international aircraft noise certification and phaseout rules for certain aircraft. Most airports have noise limits and budgets. In the United States the Department of Transportation ("DOT") and the Federal Aviation Authority ("FAA") have authority under the Aviation Safety and Noise Abatement Act of 1979, as amended and recodified, and under the Airport Noise and Capacity Act of 1990, to monitor and regulate aircraft engine noise. Noise standards in the U.S. have been codified most recently in 1999 by FAR (Federal Aviation Regulation) Part 36 - Noise Standards: Aircraft Type and Airworthiness Certification. A mandate went into effect January 1, 2000, requiring that all operations into and out of U.S. airports must be made with Stage 3 (the most strict regulated so far) noise level compliant airplanes. Stage 3 aircraft are required to be about 12% quieter than phased out Stage 2 aircraft. The CAEP is continuing to evaluate further noise reductions and regulations and has begun work on Stage 4 standards that could be codified within one to two years and be phased in over a number of years.

Numerous airports have imposed additional restrictions on airplane noise levels, noise budgets, mandatory flight paths and runway restrictions, which limit the ability of carriers to increase services or operate as desired at these airports.

Traditional noise reduction methods are typically passive consisting of mufflers and baffling techniques. More active techniques may employ mixing inlet air with exhaust gases to reduce exhaust velocity. These various methods generally provide limited noise reduction and may add weight and reduce operating efficiency of engines. Many older Stage 2 aircraft are flying today because of inefficient "hush-kits" used to quiet the aircraft to meet Stage 3 compliance. The cost to hush-kit an aircraft such as a Boeing 737 can approach $2 million.

The science of noise cancellation and the ability to create a sound wave 180 degrees out of phase with the original sound wave to interfere and cancel is well known. Noise cancellation algorithms and systems have been developed for a variety of uses ranging from headphones to industrial machinery. These methods generally use a speaker to produce the interfering and canceling wave.

Use of active electronic noise cancellation technology in jet and turbine engines has not been practical, although various methods have been proposed by others, due to the difficulty in getting a timely wave to the source of the sound. ASI's patented technology uses the internal hot gas plasma as the speaker element to create a phase inverted wave to interfere with the acoustic noise wave inside a jet engine.

While it is not practical to eliminate the noise of a jet engine, even small reductions of several decibels may provide benefits sufficient to justify the cost of this form of noise reduction if it can be successfully commercialized. A decibel (dB) is a logarithmic unit of measure for sound pressure levels. A 3 dB change typically relates to a doubling of the level. Typical conversational speech at one foot is about 60 decibels, the average pain level is 130 dB and jet engine noise levels can approach 160 Db at close range. On takeoff typical Stage 2 aircraft projected noise at 97 dB and the newer Stage 3 aircraft project sound at about 87 dB.

Theory suggests that our method of sound reduction may smooth the turbulence exiting a jet engine and thereby possibly provide improvement in operating efficiency or performance that could reduce operating costs.

Plasma Sound Reduction Market
We believe that our plasma sound reduction technology may have applications in most jet and gas turbine engine applications whether for aircraft, industry or ships. We may have the opportunity to make certain non-conforming jet engines or aircraft become conforming to existing noise regulations thereby increasing the value of older engines. This could have an impact on existing aircraft.

Our goal is to license the technology to either engine producers or others engaged in the business of servicing or providing technology for jet engines.

University of Mississippi
In September 2002 we entered into a contract with the University of Mississippi's National Center of Physical Acoustics ("NCPA") to perform the first phase of experimental work on our method of jet engine noise reduction. We believe this study provided experimental validation of our method of active jet noise control.