Embattled plane-maker Boeing on Monday took out full-page advertisements in major Japanese newspapers as it tries to piece together its reputation in the wake of the worldwide Dreamliner grounding.
The US manufacturer is fighting a rearguard action in Japan, the biggest single market for its troubled 787, which has been parked up around the globe since battery problems on two separate Japanese-owned planes in January.
"We deeply apologise to Japanese customers and companies affected for the trouble and concern caused by our new Boeing 787," Boeing said in the ad, which has a photograph of an airborne Dreamliner.
"We have suspended all flights since the trouble over batteries on the 787 emerged, but we have introduced safety measures to address all possible causes," it said.
"If any trouble such as heating emerges, new casing and exhaust systems will prevent any impact on the safety of flights and passengers and allow the plane to complete a safe flight to its destination," it said.
The advertisement came after a modified Dreamliner took to the skies over Tokyo on Sunday with top Boeing and All Nippon Airways (ANA) executives aboard.
The US Federal Aviation Authority on Thursday issued a formal approval of Boeing's 787 battery fix, clearing the way for the aircraft to fly again.
ANA and domestic rival Japan Airlines (JAL) account for around half the 50 Dreamliners in service worldwide and regaining the confidence of Japan's flying public will be key if Boeing is to see returns on its vast investment in the next-generation plane.
Despite Sunday's successful test flight, it could be at least a month before all the battery fixes are put in place and the entire fleet is back in the air.
Between mid January -- when the 787s were grounded -- and the end of May, ANA has cancelled a total of 3601 international and domestic flights, while JAL has cancelled or reduced a total of 766 flights, company spokesmen said Tuesday.
"We express our deep gratitude towards passengers, airlines, suppliers and the investigating authorities in each country... for their support on the occasion of resuming operations of the completely modified 787," Boeing said in the ad.
The ad appeared in five national newspapers and a major regional paper, including the Yomiuri, the Asahi, and the Mainichi, three of the world's four largest-selling newspapers, with combined morning edition sales of more than 21 million copies.
Newspaper officials declined to discuss how much Boeing had paid for the ads, but Yomiuri company documents say a full page costs around 48 million yen ($A470,000). The same document says a similar ad in the Asahi sells for around 40 million yen.
JAL said Tuesday its net profit in the fiscal year to March fell 8.0 per cent to $US1.8 billion ($A1.7 billion), and added it was "trying to minimise" the financial impact from the three-month grounding.
ANA said its net profit was up 53.1 per cent, despite the Dreamliner woes.