(a) For the purposes of this part:

(1) A check pilot (airplane) or check flight engineer (airplane) is a person who is qualified, and permitted, to conduct flight checks or instruction in an airplane for a particular type airplane.

(2) A check pilot (FSTD) or check flight engineer (FSTD) is a person who is qualified to conduct flight checks or instruction-only in an FSTD for a particular type airplane.

(3) Check pilots and check flight engineers are those persons who perform the functions described in § 121.401(a)(4).

(b) No certificate holder may use a person, nor may any person serve as a check pilot or check flight engineer in a training program established under this subpart unless, with respect to the airplane type involved, that person—

(1) Holds the pilot certificates and ratings required to serve as a pilot in command or a flight engineer certificate, as applicable, in operations under this part;

(2) Has satisfactorily completed the appropriate training phases for the airplane, including recurrent training, that are required to serve as a pilot in command or flight engineer, as applicable, in operations under this part;

(3) Has satisfactorily completed the appropriate proficiency or flight checks that are required to serve as a pilot in command or flight engineer, as applicable, in operations under this part;

(4) Has satisfactorily completed the applicable training requirements of § 121.413; and

(5) Has been approved by the Administrator for the check pilot or check flight engineer duties involved.

(c) Completion of the requirements in paragraphs (b)(2), (3), and (4) of this section, as applicable, shall be entered in the individual's training record maintained by the certificate holder.

(d) A check pilot (FSTD) and check flight engineer (FSTD) must accomplish the following—

(1) Fly at least two flight segments as a required crewmember for the type airplane involved within the 12-month period preceding the performance of any check pilot or check flight engineer duty in an FSTD; or

(2) Satisfactorily complete an approved line-observation program within the period prescribed by that program and that must precede the performance of any check pilot or check flight engineer duty in an FSTD.

(e) The flight segments or line-observation program required in paragraph (d) of this section are considered to be completed in the month required if completed in the calendar month before or in the calendar month after the month in which it is due.

(f) A person who serves as a required flightcrew member while performing check pilot or check flight engineer duties must also meet the requirements of this chapter for the duty position in which they are serving.