AD 2022-02-15 Retains The Actions Of AD 2020-12-06 And Corrects The Citation To The AFM

The FAA is superseding Airworthiness Directive (AD) 2020-12-06 for all Gulfstream Aerospace Corporation (Gulfstream) Model G-IV airplanes.

AD 2020-12-06 required replacing the nose wheel steering servo valve manifold, incorporating revised operating procedures into the airplane flight manual (AFM), doing a records inspection for any incidents of un-commanded nose wheel steering turns, and reporting the results to the FAA. Since the FAA issued AD 2020-12-16,  the FAA determined that a typographical error was made in citing one of the AFM documents. This AD retains the actions of AD 2020-12-06 and corrects the citation to the AFM. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective February 24, 2022.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2020-12-06, Amendment 39-21141 (85 FR 36143, June 15, 2020) (AD 2020-12-06).

AD 2020-12-06 applied to all Gulfstream Model G-IV airplanes and required replacing the nose wheel steering servo valve manifold, incorporating revised operating procedures into the AFM, doing a records inspection for any incidents of un-commanded nose wheel steering turns, and reporting the results to the FAA. The FAA issued AD 2020-12-06 to prevent moisture from entering the nose steering wheel servo valve, which could freeze and cause an un-commanded nose wheel steering position during touchdown.

The NPRM published in the Federal Register on October 26, 2021 (86 FR 59062). The NPRM was prompted by a determination that a typographical error was made in citing the title of the AFM required by paragraph (g)(3) of AD 2020-12-06. The paragraph incorrectly references the document number as “FAC-AC-G400-OPS-0001” instead of “GAC-AC-G400-OPS-0001.” In the NPRM, the FAA proposed to retain the actions of AD 2020-12-06 and to correct the citation to the AFM. The FAA is issuing this AD to address the unsafe condition on these products.

FMI: www.regulations.gov