US regulators are instructing Boeing 787 operators to install new software for the generator control unit, intended to address an issue relating to an electrical power glitch.
Analysis of the aircraft’s systems found that a 787 powered continuously for 248 days could lose all alternating current electrical power as a result of the control units simultaneously entering fail-safe mode.
The US FAA had responded with a repetitive maintenance task centred on deactivation of electrical power on the twinjet type.
It has detailed a new airworthiness directive instructing operators to install new software for the generator control unit. The directive takes effect from 20 November and states that it affects 55 US-registered aircraft.