MH370: could expired batteries play a part in disappearance?

Paraic O’Brien in June 2014 with Loughborough University aviation safety researcher, David Gleave, explaining black boxes.

An interim report into the disappearance of flight MH370 has provided details on how radars had tracked the plane going off course to issues concerning the battery of the flight data recorder’s underwater locator beacon.

However, it did not identify a definitive cause for the disappearance, adding there was nothing suspicious in the financial, medical or personal histories of pilots or crew.

Read more: MH370 searchers may 'go back to the drawing board'

MH370 vanished from radar screens shortly after taking off from Kuala Lumpur, bound for Beijing, early on 8 March last year, becoming one of the greatest mysteries in aviation history.

Investigators believe the plane, carrying 227 passengers and 12 crew, was flown thousands of miles off course before eventually crashing into the ocean off Australia.

Interactive map: the disappearance of MH370

The investigation team led by Malaysia with experts from various countries including the US, Britain, China, France and Australia confirmed in its interim report that the flight’s data recorder’s underwater locator beacon had not been replaced because the engineering department’s computer system was not properly updated.

The significance of this was not apparent but it would mean that searchers may have a lesser chance of finding the plane, even if they were in its vicinity.

Battery life

Captain Mike Vivian, former head of UK Civil Aviation Authorities flight operations department, said: “It’s not like a conventional battery where it runs out and it stops working.

“In fact, the report makes clear that there is reason to believe it probably continued working and it will just fade out, so to speak. But these batteries have a long life. Something in the order of about six years. And the other one worked, was within time.

It should have been replaced. There’s no doubt about it. Captain Mike Vivian

“My own personal view is that this was not time-critical. It should have been replaced. There’s no doubt about it. The report makes that clear. But it would be quite wrong to draw the inference, quite wrong to draw the inference that this issue, these time-critical issues, had been missed by this airline because there’s no evidence to suggest that was the case at all.”

The search for the missing jetliner, along a rugged 60,000 sq km patch of sea floor some 1,600 km west of the Australian city of Perth, will likely finish in May.