Rapid fault isolation of F/A-18E/F fibre channel network avionics

Rapid fault isolation is critical to maintaining F/A-18E/F aircraft availability at a high level. Fiber Optics communication link faults on the F/A-18E/F aircraft require a method to fault isolate to the failed avionics Weapons Replaceable Assembly (WRA) in a link consisting of two WRAs and the fiber optic cabling between them. To reduce aircraft downtime a test method providing quick test setup and performance, minimal operator training and minimal items of support equipment is required. Fiber optic cabling test and repair equipment is commonly deployed to perform fault isolation of the aircraft fiber optic cable plant. However, if the cabling tests good, the remaining ambiguity group consists of the two WRAs in the failed link. WRA Built-in Test (BIT) typically excludes the laser transceiver of each WRA, resulting in an ambiguity in the reported link failure. An on-aircraft method to rapidly determine which WRA should be removed and replaced is required. Boeing has developed a patent applied for method [1] to perform a simple bi-directional fibre channel protocol interface test, based upon the expected sequence of two low level primitives as defined in the Fibre Channel standards [2, 3, 4]. Under a Navy contract, Boeing has implemented this method in a hand-held Fibre Channel Network Test Set (FCNTS) which performs an interface test to determine which WRA in the failed link should be removed and replaced. Capability has also been included to verify communication bus operation. uni-directional The FCNTS has completed development, environmental qualification and aircraft interface testing. Initial production units have been delivered and deployed for operational use.