; and (2) by striking the period at the end and inserting , or such aerospace rulemaking committees as the Secretary shall designate. . 565. Aviation fuel (a) Use of unleaded aviation gasoline The Administrator shall allow the use of an unleaded aviation gasoline in an aircraft as a replacement for a leaded gasoline if the Administrator— (1) determines that the unleaded aviation gasoline qualifies as a replacement for an approved leaded gasoline; (2) identifies the aircraft and engines that are eligible to use the qualified replacement unleaded gasoline; and (3) adopts a process (other than the traditional means of certification) to allow eligible aircraft and engines to operate using qualified replacement unleaded gasoline in a manner that ensures safety. (b) Timing The Administrator shall adopt the process described in subsection (a)(3) not later than 180 days after the later of— (1) the date on which the Administration completes the Piston Aviation Fuels Initiative