All Nippon Airways, the world’s biggest operator of Boeing 787 Dreamliner jets, announced it is canceling nine domestic flights on Friday — and possibly 300 in the next month — because of a corrosion problem with the plane’s engines.

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All Nippon Airways (ANA), the world’s biggest operator of Boeing 787 Dreamliner jets, announced Thursday in Tokyo it is canceling nine domestic flights Friday because of a corrosion problem with the plane’s engines.

The airline may have to scrap more than 300 Dreamliner flights through the end of September as it moves to replace parts inside the engines on a portion of its 787 fleet, Takeo Kikuchi, a deputy senior vice president of engineering and maintenance at ANA, told reporters Thursday in Tokyo.

The airline’s fleet of 50 787s are all powered by Rolls-Royce engines.

About 38 percent of all the 787s in service are powered by those engines, while the rest are outfitted with General Electric engines.

“We have learned of a possible issue with a component in the Rolls-Royce engines on a limited number of Boeing 787 aircraft,” ANA said in a statement. “Safety is our top priority, so we are communicating closely with Rolls-Royce and Boeing and performing inspections and maintenance on the aircraft involved.”

The Federal Aviation Administration said in a statement the issue stems from sulfidation-corrosion cracking of turbine blades. The U.S. regulator “has reviewed the problem and determined it is not a safety concern.”

There are no U.S.-registered Boeing 787 aircraft with Rolls-Royce engines.

ANA will replace medium-pressure turbine blades in the engines where cracking has been detected, Kikuchi said.

Engine failures

Earlier Thursday, before the airline announced the flight cancellations, air traffic control authorities instructed ANA Flight 241, in flight from Tokyo to Fukuoka, to return to Tokyo after one of its 787 engines failed.

ANA previously had an engine problem on a Boeing 787 in February, when the plane returned to Kuala Lumpur airport in Malaysia after receiving a warning that the temperature of the exhaust gas from its right engine was very high, forcing the engine to be shut down.

ANA encountered the issue of corrosion in turbine blades three times since February, most recently Aug. 20, and has been in talks with Rolls-Royce on the issue since March, Kikuchi said.

Rolls-Royce said it is working to minimize the impact on flights.

“This issue is limited to a small proportion of the ANA fleet,” a Rolls-Royce spokesman said in response to questions about whether other airlines’ fleets may be affected.

The British company “will update the market if we believe any further action is required,” the spokesman said.

Short-haul flights and corrosion

The European Aviation Safety Agency is “considering” releasing a service bulletin recommending action by carriers in Europe, a spokeswoman said by email.

Unlike most 787 operators, ANA uses the jet for short flights on Japanese domestic routes.

Flying shorter flights would produce more wear and tear on an engine designed to spend 10 or more hours cruising between continents, said Robert Mann, an aviation consultant.

Corrosion caused by sulfides could be caused by the “combination of higher temperature stresses in the climb portion” of flight, followed by shorter than typical periods at cruising altitude, he said.

Mann likened the situation to the pressure on the exhaust system of a car driven only short distances.

“The engine never heats up fully to drive the moisture out the exhaust system. Then it shuts down, and condensation causes the rust to gather,” he said.

Financial impact

ANA, which was the launch customer for the 787 in 2011, operates almost a third of Dreamliners globally that fly with the Rolls-Royce Trent 1000 engines, according to a Morgan Stanley research report.

This isn’t the first time corrosion has been found in the Rolls-Royce power plants. The issue cropped up in the Trent 1000 gearboxes in 2012 and was quickly resolved, Jaime Rowbotham, an analyst at Morgan Stanley, said in a note to clients Thursday.

Rolls-Royce announced at the Farnborough Air Show last month that European safety regulators had certified an updated version of the Trent 1000 that borrows technology developed for a newer engine powering Airbus Group’s A350 jetliners.

“We expect the new derivative will have been designed to avoid the issues of its predecessor,” Rowbotham wrote.

Kikuchi said ANA expects to lose 55 million yen ($548,000) from Friday’s cancellations. The company doesn’t know the total financial impact at this time, he said.

Despite its early, headline-grabbing struggles, when all 787s were grounded for more than three months in 2013, the 787 has evolved into one of the most dependable planes in service, with a dispatch reliability of more than 99 percent, according to Boeing.

Just last week, at a celebration in Everett of ANA’s 50th Dreamliner delivery from Boeing, Hideki Kunugi, senior vice president of ANA Americas, praised the reliability of the airplane.