Boeing Co is conducting ground and flight tests of its 787 Dreamliner with a revamped lithium-ion battery system in an effort to get the jets flying again after all 50 were grounded in mid-January following two separate battery incidents.
Japanese airlines All Nippon Airways <9202.T> and Japan Airlines <9201.T> are the two biggest Dreamliner customers. ANA, the launch customer, will be the first to have its jets fixed.
Here are the steps that Boeing, aviation authorities and the airlines are expected to go through before the aircraft can return to the air, according to Japan's Civil Aviation Bureau and other sources.
BOEING CARRIES OUT AND COMPLETE TESTS
Boeing is conducting ground and flight tests to check the new lithium-ion battery system that it plans to install in the Dreamliner jets. Boeing said earlier this week more than half of the testing is complete with the remaining ground and flight tests set to occur within several days.
The company is planning to conduct one more certification test flight. A U.S. government official told Reuters that Boeing may carry out the test flight on Friday.
BOEING SUBMITS TEST RESULTS TO AUTHORITIES FOR ASSESSMENT
Boeing will submit the test results, data and analyses to both the U.S. Federal Aviation Administration (FAA) and Japan's Civil Aviation Bureau (CAB). The authorities will then assess whether to certify the proposed new battery system.
CAB official Shigeru Takano said on Friday that he cannot predict how long it will take for the authorities to reach a decision.
AUTHORITIES CERTIFY THE PROPOSED FIX
Once the assessment is done, the FAA and CAB could decide to certify the proposed fix. The certifications by the U.S. and Japanese authorities are likely to come around the same time.
FAA APPROVES BOEING'S "SERVICE BULLETIN"
The "service bulletin" is a document to be prepared by Boeing that contains technical information and detailed explanations of the battery system fix. The FAA will need to approve this. Once approved, Boeing will issue the bulletin to its customers that operate the Dreamliner.
AUTHORITIES REVISE AIRWORTHINESS DIRECTIVE
The FAA on January 16 issued an emergency airworthiness directive that grounded the Dreamliner until operators can demonstrate the lithium-ion batteries are safe. Japan's CAB also issued a similar directive, called the "technical circular directive."
Once the fix is certified and the service bulletin is approved, the FAA is likely to revise that airworthiness directive.
How exactly it will do so has yet to be decided, but the FAA could note in the airworthiness directive that Dreamliner operators cannot fly the aircraft until certain fixes are installed onto the jet, CAB's Takano said. Japan's CAB is also likely to revise its technical circular directive in a similar way, he said.
BOEING ENGINEERS INSTALL THE NEW BATTERY SYSTEM
Boeing engineers, working with airlines, will install the new battery system onto the Dreamliners. A few dozen Boeing engineers are already in Japan so they can start work on the battery fix as soon as approval is received, sources have told Reuters.
AIRLINES DECIDE WHEN TO RESUME DREAMLINER FLIGHTS
Once the new battery system is installed onto the aircraft, each airline will decide on the timing of bringing the Dreamliner back into the air. Anticipating regulatory clearance, ANA will put its roughly 200 Dreamliner pilots through flight resumption simulator training so that they will be ready to fly the jets again in June, sources with knowledge of the company's operations have told Reuters.
(Reporting by Yoko Kubota; Editing by Matt Driskill)