Boeing has broadened the scope of an investigation into an electrical system malfunction that caused a United Airlines Boeing 787 to divert and make an emergency landing on 4 December and may be related to a similar problem experienced last week by a Qatar Airways 787 on a delivery flight.
Boeing originally blamed the diversion of the United flight on the failure of one of six generator control units. The United 787 landed safely in New Orleans shortly after take-off from Houston.
But the investigation has now spread to other electrical components, but Boeing declined to elaborate.
"It's not unusual to learn new facts as you analyse findings following an event like this," Boeing says.
Qatar Airways chief executive Akbar Al Baker linked the electrical problem on the United 787 to a similar issue on the most recent aircraft delivered to his airline. Boeing, however, says its technical team needs more time to know for certain whether the two events are related.
The incidents - and a public rebuke by Al Baker -- have been embarrassing to Boeing, but so far have not caused a widespread operational impact on the 787 fleet. So far, Boeing has sent no new recommendations to 787 operators based on the findings from the diversion flight by United and the delivery flight by Qatar.