14 C.F.R. § 135.321
(b)
For the purposes of this subpart, the following terms and definitions apply—
(1)
Initial training. The training required for crewmembers who have not qualified and served in the same capacity on an aircraft.
(2)
Transition training. The training required for crewmembers who have qualified and served in the same capacity on another aircraft.
(3)
Upgrade training. The training required for crewmembers who have qualified and served as second in command on a particular aircraft type, before they serve as pilot in command on that aircraft.
(4)
Differences training. The training required for crewmembers who have qualified and served on a particular type aircraft, when the Administrator finds differences training is necessary before a crewmember serves in the same capacity on a particular variation of that aircraft.
(5)
Recurrent training. The training required for crewmembers to remain adequately trained and currently proficient for each aircraft, crewmember position, and type of operation in which the crewmember serves.
(6)
In flight. The maneuvers, procedures, or functions that must be conducted in the aircraft.
(7)
Training center. An organization governed by the applicable requirements of
part 142 of this chapter that conducts training, testing, and checking under contract or other arrangement to certificate holders subject to the requirements of this part.
(8)
Requalification training. The training required for crewmembers previously trained and qualified, but who have become unqualified due to not having met within the required period the—
Notes, amendments, and revision history
Amendments
[Docket 16097, 43 FR 46783, Oct. 10, 1978, as amended by Amdt. 121-250, 60 FR 65950, Dec. 20, 1995; Amdt. 135-63, 61 FR 34561, July 2, 1996; Amdt. 135-91, 68 FR 54588, Sept. 17, 2003; Docket FAA-2019-0360, Amdt. 135-145, 89 FR 51430, June 18, 2024]
Authority
Authority: 49 U.S.C. 106(f), 40113, 41706, 44701-44702, 44705, 44709, 44711-44713, 44715-44717, 44722, 44730, 45101-45105; Pub. L. 112-95, 126 Stat. 58 (49 U.S.C. 44730).
Source
Source: Docket 16097, 43 FR 46783, Oct. 10, 1978, unless otherwise noted.
Amendments
[Docket 16097, 43 FR 46783, Oct. 10, 1978, as amended by Amdt. 121-250, 60 FR 65950, Dec. 20, 1995; Amdt. 135-63, 61 FR 34561, July 2, 1996; Amdt. 135-91, 68 FR 54588, Sept. 17, 2003; Docket FAA-2019-0360, Amdt. 135-145, 89 FR 51430, June 18, 2024]