Section 63.59 - Retesting after failure(a) An applicant for a flight navigator certificate who fails a written or practical test for that certificate may apply for retesting- (1) After 30 days after the date he failed that test; or(2) Before the 30 days have expired if the applicant presents a signed statement from a certificated flight navigator, certificated ground instructor, or any other qualified person approved by the Administrator, certifying that that person has given the applicant additional instruction in each of the subjects failed and that person considers the applicant ready for retesting.(b) A statement from a certificated flight navigator, or from an operations official of an approved navigator course, is acceptable, for the purposes of paragraph (a)(2) of this section, for the written test and for the flight test. A statement from a person approved by the Administrator is acceptable for the written tests. A statement from a supervising or check navigator with the United States Armed Forces is acceptable for the written test and for the practical test.(c) If the applicant failed the flight test, the additional instruction must have been administered in flight.Doc. No. 1179, 27 FR 7970, Aug. 10, 1962, as amended by Amdt. 63-19, 43 FR 22640, May 25, 1978