; (2) air carriers with a low-cost or ultra-low-cost business model; (3) regional air carriers; (4) large hub airport sponsors and operators; (5) medium hub airport sponsors and operators; (6) small hub airport sponsors and operators; (7) nonhub airport sponsors and operators; (8) ticket agents; (9) representatives of intermodal transportation companies that operate at airports; (10) airport concessionaires; (11) nonprofit public interest groups with expertise in consumer protection matters; (12) senior managers of the FAA Air Traffic Organization; (13) aircraft manufacturers; (14) entities representing individuals with disabilities; (15) certified labor organizations representing aviation workers, including— (A) FAA employees; (B) airline pilots working for air carriers operating under part 121 of title 14, Code of Federal Regulations; (C) flight attendants working for air carriers operating under part 121 of title 14, Code of Federal Regulations; and (D) other customer-facing airline and airport workers; (16) other organizations or industry segments as determined by the Secretary; and (17) other Federal agencies that directly interface with passengers at airports. (c) Vacancies A vacancy in the advisory committee under this section shall be filled in a manner consistent with subsection (b). (d) Travel expenses Members of the advisory committee under this section shall serve without pay but shall receive travel expenses, including per diem in lieu of subsistence, in accordance with subchapter I of chapter 57 of title 5, United States Code. (e) Chair The Secretary shall designate an individual among the individuals appointed under subsection (b) to serve as Chair of the advisory committee. (f) Duties The duties of the advisory committee shall include— (1) evaluating ways to improve the comprehensive passenger experience, including— (A) transportation between airport terminals and facilities; (B) baggage handling; (C) wayfinding; (D) the security screening process