Japan's ANA is to test one of its modified Dreamliner jets on Sunday, three months after the worldwide fleet of 787s was grounded, as Boeing seeks to reassure passengers that the planes are safe.
All Nippon Airways has the world's largest fleet of the next-generation planes and Sunday's flight will have the company's chairman and Boeing's CEO on board, with both of them anxious to put the damaging crisis behind them.
The US Federal Aviation Administration and other regulators grounded the worldwide Dreamliner fleet in mid-January after failures of the lithium-ion batteries on the jetliner caused fires on board two aircraft.
Following months of investigations, the FAA on Thursday issued formal approval of Boeing's battery fix, clearing the way for the troubled aircraft to fly again. Japanese regulators gave their green light on Friday.
Speaking in Tokyo on Saturday, Mike Sinnett, Boeing's chief project manager for the Dreamliner programme said the test flight showed the faith that the US aircraft manufacturer placed in the battery fix.
"What it represents is... the depth of confidence that (Boeing CEO) Ray Conner has in the series of design solutions we have brought forward," Sinnett told reporters.
The test flight, to and from Tokyo's Haneda airport, will also have ANA Chairman Shinichiro Ito on board, according to the airline, which already has 17 Dreamliners and dozens more on order.
"While we deeply regret the impact this has had to our customers and to the flying public, especially here in Japan where so many of these airplanes are operated, we believe our solution is comprehensive and we know that our airplane is safe," Sinnett said.
ANA and domestic rival Japan Airlines (JAL) account for around half the 50 Dreamliners in service worldwide, but it could still be at least a month before they can complete all the battery fixes and get their planes in the air.
Although the exact cause of the battery failures had yet to be pinpointed -- as noted by the FAA on Thursday -- Sinnett insisted that the refitted planes were safe to fly.
"Even if we missed the root cause, we have identified 80 potential causal factors and we have addressed all of them in the design," he said.
Sinnett said the Japanese civil aviation authorities had expressed their belief that "any potential causes have been addressed in our solution. We still know that even if we missed something, the airplane remains absolutely safe".
He explained that the solution for the batteries eliminated the potential for fire and heat to get into the airplane. "No matter what happens to the battery, regardless of the root cause, the airplane is safe," he said.
He added that more than 300 people in 10 teams were modifying Dreamliners around the world. "In fact, nine airplanes are already almost complete."
Sinnett said it normally takes about five days to refit a 787 but declined to say when he expected the whole process to be complete.
Japan's transport ministry has said the planes will still have to undergo stringent testing and monitoring before they can return to service.
Japanese reports earlier this month said ANA was looking to bring back the Dreamliner for domestic service on June 1 and JAL, which flies the Dreamliner only on international routes, plans to resume the same month.
The FAA decision capped a difficult three months for Boeing and its 787 customers, who have had to cancel thousands of flights and rearrange schedules after the grounding.
Other airlines flying the Dreamliner include Ethiopian Airlines, which on Saturday became the first carrier to resume flying the Boeing 787 with a commercial flight from Addis Abbaba, and Polish carrier LOT.