GEEZE- IMO any software that allows all systems to fail at the same time- even under extreme unlikely events is fubar !
FAA orders new 787 electrical fix to prevent power failure - 4/30/2015 - Flight Global
ll Boeing 787 operators will be required to periodically deactivate the electrical system to avoid a problem with a newly-discovered software bug that could cause the aircraft to lose alternating current (AC) power, the US Federal Aviation Administration says in a new airworthiness directive.
The agency adopted the final rule after Boeing reported the results of a laboratory test showing a total loss of power is possible if the generator control units run continuously for eight months, says the FAA’s 30 April notice in the Federal Register.
The binding airworthiness directive is being published less than two weeks after Boeing privately alerted operators about the problem, the company says in a statement to Flightglobal.
It is rare for a commercial aircraft to remain powered on for eight months with no interruptions.
Goes on !
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All six power generating systems are managed by a corresponding generator control unit (GCU). Boeing’s laboratory testing discovered that an internal software counter in the GCU overflows after running continuously for 248 days, according to the FAA. The overflow causes all four GCUs on the engine-mounted generators to enter failsafe mode at the same time.