Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Airbus Industrie Model A320, A321, A330, and A340 series airplanes. This proposal would require repetitive testing of certain fire shutoff valves (FSOV's) on the left and right engines, repetitive checks of certain parts on the FSOV motors, and replacement of discrepant valves with modified valves. It would also require modification of FSOV seals and motors as terminating action for the repetitive testing and check requirements. This proposal is prompted by reports indicating that FSOV's are not closing completely during maintenance testing. The actions specified by the proposed AD are intended to prevent the flow of hydraulic fluid to the engine in the event of fire which, if not corrected, would fuel the fire, and lead to the loss of fluid in associated hydraulic systems, causing those systems to fail.