Path to Alternative

Jet Fuel Readiness

The goal of the Commercial Aviation Alternative Fuels Initiative® (CAAFI®) is to facilitate the development and deployment of alternative jet fuels that offer equivalent levels of safety and performance and compare favorably on cost with petroleum based jet fuel, and that offer environmental improvement and security of energy supply for aviation. Over time, the leadership of CAAFI has found that many are not aware of the process by which the Fischer-Tropsch (FT) and hydroprocessed esters and fatty acids (HEFA) fuels were successfully developed and deployed.

The "Path to Alternative Jet Fuel Readiness" briefing document was developed by the CAAFI R&D Team to outline the process of fuel development, qualification and certification and the role of CAAFI in facilitating the process. It is intended for use by individuals and organizations interested in producing alternative fuels.

The "Path to Fuel Readiness" document provides information on how to become involved with the aviation community, the testing and environmental evaluations required to show the fuel's suitability for aviation use, and how to best facilitate ASTM International certification for a new fuel.

Download Document Now  Path to Alternative Jet Fuel Readiness Document

The "Path to Fuel Readiness" document also refers to several CAAFI communication tools designed to aid in the communication of both the necessary steps to be taken and the progress of alternative jet fuel projects:

1. The Fuel Readiness Level (or FRL) provides guidance on fuel technical development and certification testing;
2. The FRL Exit Criteria, a checklist detailing what is performed at each FRL level;
3. The Feedstock Readiness Level (FSRL) Tool, developed in collaboration with the US Department of Agriculture. tracks development and availability of the raw materials (or feedstocks) required to make alternative jet fuels;
4. The Guidance for Selling Alternative Fuels to Airlines provides to serve as a roadmap for potential producers and other supply-chain participants contemplating purchase agreements with airlines for non-petroleum-derived jet fuels.
5. The Environmental Progression provides guidance on performance of necessary environmental analyses.

These documents are outlined and available below.

For further information about any of these documents, please contact us at

Fuel Readiness Level

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 contained in this document. 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.

The roadmaps and milestone databases developed and maintained by CAAFI use FRL to help organize and track the research and development milestones 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.

Download Document Now  Fuel Readiness Level Document

FRL Exit Criteria

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.

Download Document Now  FRL Exit Criteria Document

Feedstock Readiness Level

As a result of the implementation of the FRL, the CAAFI R&D team identified the need for a separate evaluation of feedstock readiness to complement the FRL. CAAFI therefore approached the US Department of Agriculture (USDA) to collaborate on the development of a Feedstock Readiness Level (FSRL), which was accomplished under a Memorandum of Agreement between USDA and the Federal Aviation Administration (FAA).

The Feedstock Readiness Level (FSRL) Tool is a companion to the CAAFI® Readiness Level (FRL) Tool. The FSRL Tool provides a means of tracking development and availability of the raw materials (or feedstocks) required to make alternative jet fuels. In detailing the steps necessary to establish feedstock production in the commercial sector, a complete supply chain systems context is implied. The FSRL Tool covers four components: (1) Production, (2) Market, (3) Policy - Program Support and Regulatory Compliance, and (4) Linkage to Conversion Processes. The FSRL Tool components parallel the FRL. This approach provides an integrated way to demonstrate the mutual requirements of feedstocks and conversion technologies.

Download Document Now  Feedstock Readiness Level Document

Guidance for Selling Alternative Fuels
to Airlines

CAAFI has published this document to serve as a roadmap for potential producers and other supply-chain participants contemplating purchase agreements with airlines for non-petroleum-derived jet fuels. It outlines key steps and criteria for potential producers to engage with airlines and highlights how and when CAAFI can help. The report was co-authored by CAAFI Business Team Leaders Dr. Bruno Miller and John Heimlich in close consultation with the heads of Airline for America (A4A) member airline fuel management departments.

To assist producers and investors, the paper constitutes a central source of answers to the following questions:
  • Why are airlines interested in commercial-scale alternative jet fuel production?
  • What are the airlines' requirements for contemplating the purchase of alternative jet fuel?
  • What are airlines willing to do to help commercialize alternative jet fuel?
  • What does a "term sheet" look like?
  • What is the best way to engage with airlines?
  • How can CAAFI help?

In addition, it includes a matrix of CAAFI readiness tools with recommended avenues for commercial engagement at various stages of development. The readiness tools are key communication protocols to help airlines, producers, and other stakeholders to explicitly understand one another's progress levels, by providing visibility and transparency into the current and projected state of aviation alternative fuel development.

CAAFI expects to augment this guidance in the future with appendices including additional lessons-learned and non-proprietary details from actual commercialization success examples as they occur.

Download Document Now Guidance for Selling Alternative Fuels to Airlines Document

Environmental Progression

Coming soon. Please check back.

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Fuel Readiness Level (or FRL)

FRL Exit Criteria

Feedstock Readiness Level (FSRL) Tool

Guidance for Selling Alternative Fuels to Airlines

Environmental Progression