Lichtenstein, Germany – It is now clear, the future of aviation is in working towards a cleaner environment through advanced technology. The U.S. Federal Aviation Administration (FAA) has already proven it is fully committed to this end. The FAA is currently working on finding an unleaded fuel capable of replacing the industry standard 100 Octane Low Lead (100LL) by the year 2018. As the availability of 100 LL aviation fuel continues to decline, the price is forecast to climb until it is completely phased out. For years a viable alternative has already existed: Centurion Jet Fuel Engines. When it comes to jet fuels, environmentally responsible measures are already being successfully promoted. One example for these new, cleaner fuels is the production of eco-friendly jet fuels from biomass or by Fischer-Tropsch process. The technical standards for these so-called semi-synthetic jet fuels (SSJFs) are set by ASTM International. The latest specifications regulate the blending of SSJFs with conventional kerosene. To this effect, the Federal Aviation Administration (FAA) published an information bulletin NE-11-36 in September 2011 announcing that the new SSJFs can be used in aircraft and engines approved for use with Jet A or Jet A-1 fuels. This applies without limitation to Centurion piston aircraft engines. The company has worked with the precursors to SSJFs for years and Centurion engines have been undergoing tests with the new fuels for over a year. These tests have shown that Centurion engines are not only perfectly suited for the new SSJFs, but for fully synthetic fuels as well. Owners of Centurion engines will in the future be able to tank up with these new fuels without worry.
Background
ASTM International (formerly the American Society for Testing and Materials) is an international standards organization headquartered in West Conshohocken, Pennsylvania, USA. It publishes technical standards for goods and services. ASTM International’s work in the area of aviation includes the technical specifications for fuels. Certifications from the aviation authorities are based on these standards.
The ASTM International standard D1655 is the "Standard Specification for Aviation Turbine Fuels," meaning kerosenes such as Jet A and Jet A-1. The ASTM standard D7566 "Standard Specification for Aviation Turbine Fuel Containing Synthesized Hydrocarbons" regulates the blending of conventional kerosene with alternative feedstocks. In July 2011, this specification was expanded to include various biofuels. D7566 fuels must show properties and performance that are essentially identical to those of conventional jet fuels according to D1655, which allows blending of D1655 fuels with components under the D7566 specification. Synthetic and semi-synthetic jet fuels previously approved according to ASTM D7566 and mixed with mineral oil-based turbine fuels that correspond to ASTM D1655 can now be re-identified as D1655 fuels when they enter the distribution system and do not need to be separately declared. As a result, it will not always be apparent to fuel suppliers whether biofuels or other SSJFs are present.
The FAA determined in September 2011 that D7566 fuels meet all of the requirements for D1655 specification and can therefore be used in all aircraft and engines that are approved to operate with D1655 fuels. Operational limits in aircraft flight manuals, operating instructions, and type certificate data sheets that specify ASTM D1655 Jet A or Jet A-1 fuel are also valid for use with D7566 fuels. However, other limitations from authorization holders can be implemented. From the manufacturer and certification holder of Centurion engines, there are no such limitations. Owners of Centurion engines therefore do not need to worry when it comes to using the new fuels. The economical and reliable Centurion engines have thereby once again shown themselves to be sustainable and environmentally friendly aircraft engines.
