ANA Holdings Inc., operator of a fleet of Boeing Co. 787 jets grounded since January after batteries overheated, said a switchboard was damaged by heat on a 787 training flight after a nut was not fully tightened.
The part was replaced and the Tokyo-based carrier will finish plane and pilot tests on schedule, Yoichi Uchida, an ANA spokesman, said by phone today. The scheduled June 1 restart for commercial 787 flights is unchanged, Uchida said.
The damage was discovered after a flight to Sapporo from Tokyo on May 4 and wasn’t related to the lithium-ion battery system, Uchida said. ANA, which operates the world’s largest fleet of 17 787 Dreamliners, is implementing Boeing battery repairs approved by the Federal Aviation Administration and Japan’s transport ministry to allow the restart of flights.
Boeing’s 787, the world’s first plastic-composite airliner, was grounded in January after two battery overheating incidents.
The Dreamliner is safe to fly, even as the cause of the battery meltdowns remains uncertain, Mike Sinnett, vice president and chief project engineer of the 787 program, said last month. Stress testing of Chicago-based Boeing’s redesigned system showed its steel casing and heat vent reduced battery overheating, he said.
ANA last week placed advertisements in Japanese newspapers to lure customers back to the aircraft as it prepares to restart flights after a more than four-month halt in commercial operations. Japan Airlines Co., the world’s second-largest Dreamliner operator, will resume 787 flights the same day.
ANA rose 2.8 percent to 220 yen as of the close in Tokyo trading today and has gained 22 percent this year, compared with a 45 percent jump in the Nikkei 225 Stock Average. JAL fell 1.3 percent to 4,900 yen.