Investigations into the cause of battery failures in Boeing 787s do not appear to have yielded any results, say two customers, increasing the possibility of a prolonged grounding of the aircraft.

Japan Airlines, which has six 787s, and upcoming operator Qantas say they are in regular contact with the airframer over the technical issues that have grounded the aircraft globally.

But JAL chairman Masaru Onishi and Qantas chief executive Alan Joyce both say that the "root cause" of the battery failures has not been found.

This is despite the "comprehensive and detailed" investigations by the NTSB, the JTSB and Boeing into the battery failures on board a JAL 787 and an All Nippon Airways 787 in January. This means that there is still no clear idea of when the grounding, which has lasted more than two weeks, will end.

"It seems like Boeing's investigation hasn't reached the stage where they can come to us and reassure us about anything yet. Their investigation hasn't progressed to the stage where they can identify the root cause of this problem," says Onishi.

"I am not exaggerating - we are contacting each other almost every day. So...they are doing their best to carry out their investigation to find the root cause of this problem. But other than that, we haven't had anything yet."

Qantas is due to get its first 787 in August and Joyce says it is still not clear what impact the investigation will have on this timeline.

"It is still early, they still haven't determined the root cause and so we are not sure what is the implication will be on the delivery. This could range from a component problem to a more significant problem, and the time and impact on the production line could vary," he adds.

While Boeing has been publicly reticent, Joyce says that it has been proactively communicating with its customers.

"Obviously those conversations are commercially confidentially, but we are always confident about what Boeing are doing. They are very proactive with daily calls to the operations people and regular calls with the senior management," says Joyce.

Source: Air Transport Intelligence news