SANDPOINT, Id --­ Initial tests of a new Catalytic Ignition (CI) system on a standard general aviation (GA) engine have successfully demonstrated the system's ability to improve engine performance while operating on multiple fuels, including Avgas, 87UL and Jet-A, without the use of magnetos. Performance improvements included increased power, reduced noise and vibration, increased lean limits, and the ability to maintain engine power without any electrical power.

The CI system is being developed by AquaLytic Technologies, Inc. (ATI, Sandpoint, ID), and was tested on a reconditioned 0-200 Continental engine, as part of a NASA Glenn Research Center Phase I SBIR contract for the General Aviation Propulsion (GAP) program. Concurrent development efforts for the CI system include small, two-stroke multi-fuel (diesel included) engines for military applications, and operation of standard internal combustion engines on aqueous alcohols.

Referred to as the "SmartPlug," the CI technology was originally developed by Automotive Resources, Inc. of San Diego, before being transferred to ATI. The SmartPlug utilizes a heated catalyst mounted inside a small precombustion chamber, with the fixed position of the catalyst determining the engine ignition timing at all rpm. An integral DC heater brings the catalyst to operational temperature for initial operation, but no electrical power is required to sustain combustion during normal operation on unleaded fuels. Flame jets from the precombustion chamber are injected into the cylinder, producing a very smooth and thorough combustion process. Roughly the same size as a sparkplug, the SmartPlug merely replaces sparkplugs in standard low compression engines, while timing and high voltage system components are eliminated. Previous tests have demonstrated its ability to allow standard two-stroke gasoline engines to operate on diesel fuel with no visible exhaust emissions, and tests using aqueous alcohol (140 proof) in a four-stroke gasoline engine demonstrated a 20% increase in horsepower with major reductions in NOx (97%), CO (94%) and HC (64%), with a 50% increase in thermal efficiency.

For the general aviation engine tests, static testing of a reconditioned 0-200 Continental engine was conducted using Avgas (100LL) and 87UL fuels, producing baseline results of 2400 rpm at wide-open-throttle (WOT). Sparkplugs and magnetos were removed and replaced by CI igniters and retested. With just one igniter per cylinder, CI performance matched spark-magneto performance on 100LL and 87UL. When the CI-configured engine was switched to Jet-A fuel (stock, carbureted), the engine rpm at WOT increased to 2475 rpm, with no visible exhaust emissions (spark-magneto configuration could not be tested with Jet-A). Noise level at five feet was reduced by 6 dB when switched from spark-magneto to CI igniters on 87UL, with a significant reduction in engine vibration as well. Cylinder head, barrel and exhaust gas temperatures for the CI-equipped engine were consistent with spark-magneto norms. While continued DC heater power was required for operation on 100LL, due to catalyst poisoning, all electrical power could be shut off without significantly impacting engine performance on 87UL or Jet-A fuels ­ a major safety advantage with the next generation of unleaded aviation fuels.

ATI is continuing development of the CI technology for multiple commercial applications, including general aviation, where the technology could eventually contribute to improved safety and reduced environmental emissions. Using the CI system, GA aircraft could operate flawlessly even with contaminated or improperly substituted fuels, and without dependence on magnetos. The target is eventual compliance with FAR Part 33.37 for Ignition Systems, with demonstration of "an ignition system of equivalent in-flight reliability." The company's major partner for CI technology applications is 2 Stroke International (2si, Beaufort, SC), a developer and manufacturer of commercial and military two-stroke engines. ATI is being assisted by MSU TechLink, a technology transfer and commercialization center in Bozeman, MT, in working with NASA, the Department of Defense, and additional commercial firms, for technology development and new applications. Additional assistance has been provided by the Idaho SBDC in Boise.

Photos and additional information are available from ATI upon request.

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