14 CFR § 60.27 - Automatic loss of qualification and procedures for restoration of qualification.
(a) An FSTD qualification is automatically lost when any of the following occurs:
(1) The FSTD is not used in the sponsor's FAA-approved flight training program in accordance with § 60.7(b)(5) or (b)(6) and the sponsor does not obtain and maintain the written statement as described in § 60.7(d)(2).
(2) The FSTD is not inspected in accordance with § 60.19.
(3) The FSTD is physically moved from one location and installed in a different location, regardless of distance.
(4) The MQTG is missing or otherwise not available and a replacement is not made within 30 days.
(b) If FSTD qualification is lost under paragraph (a) of this section, qualification is restored when either of the following provisions is met:
(1) The FSTD successfully passes an evaluation:
(i) For initial qualification, in accordance with §§ 60.15 and 60.17(c) in those circumstances where the responsible Flight Standards office has determined that a full evaluation for initial qualification is necessary; or
(ii) For those elements of an evaluation for initial qualification, in accordance with §§ 60.15 and 60.17(c), as determined to be necessary by the responsible Flight Standards office.
(2) The responsible Flight Standards office advises the sponsor that an evaluation is not necessary.
(c) In making the determinations described in paragraph (b) of this section, the responsible Flight Standards office considers factors including the number of continuing qualification evaluations missed, the number of sponsor-conducted quarterly inspections missed, and the care that had been taken of the device since the last evaluation.