Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all EMBRAER Model ERJ 170 series airplanes. This proposed AD would require 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 proposed AD is prompted by 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 proposing 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.