On June 10, 2013, FAA issued a request for candidate fuel producers to submit unleaded fuel formulations to be evaluated as replacements for 100LL (https://faaco.faa.gov). This announcement is a significant milestone in a government/industry collaborative effort to find an unleaded replacement fuel for the general aviation industry. The request for candidate fuels kicks off a multi-year R&D program that will help select the best unleaded fuel(s) with least impact on the general aviation fleet. In response to public health concerns about impacts of lead in avgas and industry uncertainty regarding the future of 100LL, FAA chartered an Aviation Rulemaking Committee to investigate the current issues relating to the transition to an unleaded fuel, and recommend the tasks necessary to investigate and resolve these issues. The UAT ARC issued their final report in February 2013.

The UAT ARC identified the following issues that must be considered in any effort to transition the aviation industry to an unleaded AVGAS:

1. An unleaded replacement fuel that meets the needs of the entire fleet does not currently exist.
2. No program exists that can coordinate and facilitate the fleet-wide evaluation, certification, deployment, and impact of a fleet-wide replacement AVGAS.
3. No market driven reason exists to move to a replacement fuel due to the limited size of the AVGAS market, diminishing demand, specialty nature of AVGAS, safety, liability, and the investment expense involved in a comprehensive approval and deployment process.
4. No FAA policy or test procedures exist to enable fleet-wide assessment and certification of a replacement unleaded fuel.
5. There is no standardized method for communicating to the industry and end-users the impacts posed by a newly proposed fuel.

The UAT ARC's five key recommendations are:

1. Implement a fuel development roadmap for avgas readiness levels that identifies milestones in the aviation gasoline development process.
2. Establish centralized testing of candidate unleaded fuels which would generate standardized qualification and certification data.
3. Establish a solicitation and selection process for candidate unleaded aviation gasolines for the centralized testing program.
4. Establish a centralized certification office to support unleaded aviation gasoline projects.
5. Establish a collaborative industry-government initiative called the Piston Aviation Fuels Initiative (PAFI) to implement the UAT ARC recommendations to facilitate the development and deployment of an unleaded avgas with the least impact on the existing piston-engine aircraft fleet.

Since the issuance of the ARC's report, the FAA and industry have taken significant steps in implementing the recommendations of the UAT ARC committee;

• The FAA established the Fuels Program Office, AIR-20 to provide focus, and to consolidate resources and expertise, which includes the Fuels Program Branch, AIR-21 � fulfilling recommendation 4 above.
• The FAA and the General Aviation Avgas Coalition have formed the PAFI Steering Group (PSG) and are working together to implement the ARC recommendations � fulfilling recommendation 5 above.
• The FAA has issued an OTA soliciting candidate fuel producers to submit their fuels into the PAFI program. The PAFI includes a test program that will put candidate fuels through a 2 phase test program resulting in a test report that can be utilized in ASTM production specification and fleetwide certification efforts � fulfilling recommendation 3 above.
• The FAA has issued the UAT Action Plan, which includes an R&D plan that supports the accomplishment of the ARC recommendations � providing options for various funding levels.

The above actions are moving us forward in accomplishing our Destination 2025 goal � A replacement fuel for leaded aviation gasoline is available by 2018 that is usable by most general aviation aircraft.