Fuel Readiness Level (FRL)
The leadership of CAAFI needed a way to classify and track progress on research, certification, and demonstration activities. A variety of scales were in use by CAAFI organizations including TRL (Technology Readiness Level) used by industry, NASA, and the Air Force and Manufacturing Readiness Level (MRL) used by the Air Force and others. Originally, an Airbus CAAFI representative developed a special TRL scale for fuel development, but it was a mixture of research achievements and production development. The CAAFI leadership team wanted a new fuel development scale that would allow for parallel fuel research activities and certification activities, as well as clearly showing how to transition activities between the CAAFI R&D, Certification, and Business & Economics teams. Also, CAAFI desired to show how these new Fuel Readiness Levels (FRL) mapped to the TRL and MRL scales also in use.
The leaders of the CAAFI Certification and R&D teams developed the FRL table. It includes descriptions that are customized to fuel research and certification events and includes specific items of interest to CAAFI members, including required fuel quantities. Note that the fuel quantities listed are from CAAFI Certification guidelines, and the Air Force uses different fuel quantities in their military fuel certification process. Color coding used to show the transition points between the CAAFI R&D, Certification, and Business & Economics teams. The CAAFI teams operate with the realization that overlap will occur, with R&D leading FRL 1-5, Certification FRL 6-7, and Business & Economics FRL 8-9. Environment Team assessment requirements will also overlap with the FRL. Preliminary assignments of environmental touchpoints are reflected in steps 3 and 8. A more detailed list of environmental due diligence needs are described in CAAFI’s Environmental Progression.
CAAFI uses the FRL to help organize and track fuel development and the process of developing, certifying, and supplying alternative fuels to commercial aviation.
The FRL was endorsed at the United Nations' International Civil Aviation Organization (ICAO) Commercial Aviation Alternative Fuels (CAAF) meeting in Rio de Janeiro in November 2009. The outcomes of that meeting can be found here.
To facilitate the use of the FRL, a checklist of exit criteria (tasks that must be accomplished to move from one FRL level to the next) was developed by CAAFI in collaboration with the Air Force Research Laboratory.
ASTM D4054 was developed to provide alternative jet fuel producers with guidance regarding testing and property targets necessary to evaluate a candidate alternative jet fuel. The ASTM D4054 data and proposed specification properties investigated through the four-tier approach are then used as the basis for continued engagement with ASTM. The certification process requires fuel producers to iterate through the defined checkpoints, and if the fuel successfully passes, this process may result in the development of a proposed annex for incorporation into ASTM D7566 as a drop-in synthetic jet fuel.
Therefore, it is important to get prospective producers engaged with the testing community as early as possible. CAAFI's intent of creating this D4054 User's Guide is to provide an index of facilities that have:
- demonstrated the technical capabilities necessary to perform the aviation fuel property testing required by D4054, and;
- expressed an interest in performing those tests in the future.
We hope this helps prospective fuel producers locate resources to support testing of their fuels for ASTM approval.
This document is not static, and as with other CAAFI guidance material, we will continue to add helpful resources and information as the need is identified.