Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model ERJ 170 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all EMBRAER Model ERJ 170 airplanes. This AD requires inspecting the hydraulic pressure tubes at the outlet of the engine-driven hydraulic pumps to determine the part and serial numbers; and replacing hydraulic pressure tubes having certain serial numbers with new hydraulic pressure tubes. This AD results from failure of a hydraulic system due to leakage of hydraulic fluid from a crack in the pipe coming from the pressure side of the engine-driven pump. We are issuing this AD to prevent cracking of the hydraulic pressure pipes, which could result in failure of hydraulic system 1 or 2 or both, and consequent reduced controllability of the airplane.