Section 135.411 - Applicability(a) This subpart prescribes rules in addition to those in other parts of this chapter for the maintenance, preventive maintenance, and alterations for each certificate holder as follows: (1) Aircraft that are type certificated for a passenger seating configuration, excluding any pilot seat, of nine seats or less, shall be maintained under parts 91 and 43 of this chapter and §§ 135.415 , 135.417 , 135.421 and 135.422 . An approved aircraft inspection program may be used under § 135.419 .(2) Aircraft that are type certificated for a passenger seating configuration, excluding any pilot seat, of ten seats or more, shall be maintained under a maintenance program in §§ 135.415 , 135.417 , 135.423 through 135.443 .(b) A certificate holder who is not otherwise required, may elect to maintain its aircraft under paragraph (a)(2) of this section.(c) Single engine aircraft used in passenger-carrying IFR operations shall also be maintained in accordance with § 135.421(c), (d) , and (e).(d) A certificate holder who elects to operate in accordance with § 135.364 must maintain its aircraft under paragraph (a)(2) of this section and the additional requirements of Appendix G of this part.Doc. No. 16097, 43 FR 46783, Oct. 10, 1978, as amended by Amdt. 135-70, 62 FR 42374, Aug. 6, 1997; Amdt. 135-78, 65 FR 60556 , Oct. 11, 2000; Amdt. 135-92, 68 FR 69308 , Dec. 12, 2003; Amdt. 135-81, 70 FR 5533 , Feb. 2, 2005; Amdt. 135-108, 72 FR 1885 , Jan. 16, 2007; 72 FR 53114 , Sept. 18, 2007