Hi,
More precise information from
NHK:
Japanese aviation authorities have uncovered a design fault in the electric wiring of a Boeing Dreamliner that made an emergency landing last month.
But officials with the Transport Safety Board say the fault has no direct connection with the aircraft's battery trouble.The 787 aircraft, operated by All Nippon Airways, landed after a battery overheated, sending out smoke.
Experts have focused on electricity flow aboard the plane because some of its lights remained on after their switches were turned off.They found that wiring was installed according to the aircraft's blueprints, but that electricity flowed differently from its intended design.They say current flowed from one battery into a circuit whose switch was supposed to be off. The battery was reportedly not the one that overheated.The officials say they will investigate the problem more closely.
So, another issue.
787 uses high current solid state switches. Same modules are used in F35. These switches (solid state relays) could fail (short) and create "strange" behavior on circuits. For example, the diode module in MAIN battery circuit if shorted needs prompt (protective) reaction from battery management or even crew members in extreme cases. A new project requires IMHO to be more alert than other mature planes. The degree of innovation in 787 is a factor to be considered with attention. Some (due components) failures could be very difficult to quick understand even for a (circuit) designer. The above news may be related to a shorted solid state relay.