Ethiopian Airlines returns Boeing 787 Dreamliner to service

A Boeing 787 Dreamliner flew from Ethiopia to Kenya on Saturday, the aircraft's first flight since battery problems led airlines worldwide to ground their fleet.

An Ethiopian Airlines Dreamliner took off from Addis Ababa and landed safely in Nairobi two hours later, having been fitted with a specially redesigned battery.

All 50 of the Dreamliners purchased around the world will receive the new batteries, which not only operate at a lower temperature, but are encased in stainless steel to prevent them interfering with the rest of the aircraft in the event of a malfunction. 

Several airlines are preparing to return their fleet to the skies after the US Federal Aviation Administration on Thursday formally declared the refitted planes fit to fly. Japanese and European safety authorities have also given their approval.

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Japan's All Nippon Airways – which, with 17 Dreamliners, has the world's largest fleet – will carry out a test flight in Tokyo on Sunday. Polish carrier LOT plans to return its two Dreamliners to service in June.

Before today, no Dreamliner had flown since mid-January, when a series of incidents linked to its lithium-ion batteries overheating led regulators to order the aircraft grounded.

The exact reason for the problems has still not been established. Boeing says it has identified 80 possible causal factors, all of which have been addressed in the battery redesign.

The global refit is expected to be finished by mid-May, having taken 300 Boeing engineers and 200,000 working hours to complete.

The three-month grounding is estimated to have cost Boeing some $600 million.