; or (C) modification or retrofitting of an aircraft. (b) Definitions In this section: (1) Crewmember The term crewmember has the meaning given such term in section 1.1 of title 14, Code of Federal Regulations. (2) Critical phases of flight The term critical phases of flight has the meaning given such term in section 121.542 of title 14, Code of Federal Regulations. (3) Part 121 The term part 121 means part 121 of title 14, Code of Federal Regulations. (c) Aviation safety Nothing in this section shall limit the authority of the Administrator relating to aviation safety under subtitle VII of title 49, United States Code. 422. GAO study and report on extent and effects of commercial aviation pilot shortage on regional/commuter carriers (a) Study The Comptroller General shall conduct a study to identify the extent and effects of the commercial aviation pilot shortage on regional/commuter carriers (as such term is defined in section 41719(d) of title 49, United States Code). (b) Report Not later than 12 months after the date of enactment of this Act, the Comptroller General shall submit to the appropriate committees of Congress a report containing the results of the study conducted under subsection (a), including recommendations for such legislation and administrative action as the Comptroller General determines appropriate. 423. Report on implementation of recommendations of Federal Aviation Administration Youth Access to American Jobs in Aviation Task Force Not later than 2 years after the date of enactment of this Act, the Secretary, acting through the Administrator, shall submit to the appropriate committees of Congress a report on the implementation of the following recommendations of the Youth Access to American Jobs in Aviation Task Force of the FAA established under section 602 of the FAA Reauthorization Act of 2018 ( Public Law 115–254 ): (1) Improve information access about careers in aviation and aerospace. (2) Collaboration across regions of the FAA on outreach and workforce development programs. (3)