Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

The FAA is adopting a new airworthiness directive (AD) for all Gulfstream Aerospace Corporation (Gulfstream) Model G-IV airplanes. This AD was prompted by reports of un-commanded nose wheel steering turns. This AD requires 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. The FAA is issuing this AD to address the unsafe condition on these products.