Two Dreamliners owned by Japan Airlines (JAL) were forced to turn back halfway.
Because there are separate technical problems.
The latest setback for Boeing manufacturers.
Toilet system failure in Tokyo
It was blamed for an electronic fault.
The flight, carrying 141 passengers, left Moscow on Wednesday night and returned about five hours in the air.
In the second incident, a Dreamliner flying to Tokyo was transferred back to San Diego because of possible problems with the de-localization of the aircraft. icing system.
Airline officials said the pilot received an error message and decided to return to San Diego for repairs after an hour of flight.
The Boeing 787 Dreamliner has had many failures, most notably the overheating of lithium batteries.
It caused the plane to stop flying the ion battery system for three months worldwide this year.
The flight resumed after the company redesigned its battery system to satisfy American aviation regulators.
Earlier this week, JAL signed the next generation of long dragon aircraft with Boeing's rival Airbus, making headlineshaul jets -
The move was welcomed by shareholders.
The company confirmed orders for 31 A350 aircraft on Monday, with a catalog value of £ 5. 9bn.
The agreement also includes the option for JAL to purchase 25 Airbus aircraft.
Historically, JAL's fleet has been dominated by Boeing, in part because of defense and security relations between the two countries and reconstruction arrangements since World War II.