Section 121.1 - ApplicabilityThis part prescribes rules governing-
(a) The domestic, flag, and supplemental operations of each person who holds or is required to hold an Air Carrier Certificate or Operating Certificate under part 119 of this chapter.(b) Each person employed or used by a certificate holder conducting operations under this part including maintenance, preventive maintenance, and alteration of aircraft.(c) Each person who applies for provisional approval of an Advanced Qualification Program curriculum, curriculum segment, or portion of a curriculum segment under subpart Y of this part, and each person employed or used by an air carrier or commercial operator under this part to perform training, qualification, or evaluation functions under an Advanced Qualification Program under subpart Y of this part.(d) Nonstop Commercial Air Tours conducted for compensation or hire in accordance with § 119.1(e)(2) of this chapter must comply with drug and alcohol requirements in §§ 121.455 , 121.457 , 121.458 and 121.459 , and with the provisions of part 136, subpart A of this chapter by September 11, 2007. An operator who does not hold an air carrier certificate or an operating certificate is permitted to use a person who is otherwise authorized to perform aircraft maintenance or preventive maintenance duties and who is not subject to anti-drug and alcohol misuse prevention programs to perform- (1) Aircraft maintenance or preventive maintenance on the operator's aircraft if the operator would otherwise be required to transport the aircraft more than 50 nautical miles further than the repair point closest to the operator's principal base of operations to obtain these services; or(2) Emergency repairs on the operator's aircraft if the aircraft cannot be safely operated to a location where an employee subject to FAA-approved programs can perform the repairs.(e) Each person who is on board an aircraft being operated under this part.(f) Each person who is an applicant for an Air Carrier Certificate or an Operating Certificate under part 119 of this chapter, when conducting proving tests.(g) This part also establishes requirements for operators to take actions to support the continued airworthiness of each aircraft.Doc. No. 28154, 60 FR 65925, Dec. 20, 1995, as amended by Amdt. 121-328, 72 FR 6912 , Feb. 13, 2007; Amdt. 121-336, 72 FR 63411 , Nov. 8, 2007