Sec. 141.33
Personnel.
(a) An applicant for a pilot school certificate or for a provisional pilot school certificate must meet the following personnel requirements:
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(3) Each instructor to be used for ground or flight training must hold a flight instructor certificate, ground instructor certificate, or commercial pilot certificate with a lighter-than-air rating, as appropriate, with ratings for the approved course of training and any aircraft used in that course.
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Sec. 141.81
Ground training.
(a) Except as provided in paragraph (b) of this section, each instructor who is assigned to a ground training course must hold a flight or ground instructor certificate, or a commercial pilot certificate with a lighter-than-air rating, with the appropriate rating for that course of training.
(b) A person who does not meet the requirements of paragraph (a) of this section may be assigned ground training duties in a ground training course, if:
(1) The chief instructor who is assigned to that ground training course finds the person qualified to give that training; and
(2) The training is given while under the supervision of the chief instructor or the assistant chief instructor who is present at the facility when the training is given.
(c) An instructor may not be used in a ground training course until that instructor has been briefed on to the objectives and standards of that course by the chief instructor, assistant chief instructor, or check instructor.