TOKYO (AFP) - The grounded 787 Dreamliner is safe, a senior Boeing executive told a press conference in Tokyo on Friday as the company looks to reassure airlines and passengers about its flagship aircraft.

"I get often asked if I think the airplane is still safe. My answer is simple. Absolutely," Mike Sinnett, the chief project engineer on the 787, told reporters.

Sinnett was speaking as part of a push by the manufacturer to explain how it planned to fix battery problems that have left 50 of the world's most advanced airplanes parked up since mid-January after two malfunctions.

He said an investigation into the incidents in the United States and Japan had proved the aircraft's safety measures had kicked in properly.

"After the battery failure the airplane responded in exactly the way we had designed and anticipated," he said.