Loose nut mars Dreamliner test

A loose nut threatened to spoil the long awaited comeback of Boeing's cutting-edge aircraft after an electrical panel fault was reported on a test flight in Japan yesterday.

The 787 Dreamliner was grounded worldwide in January after batteries overheated on jets owned by ANA and Japan Airlines. Toshifumi Kitamura / AFP

A loose nut threatened to spoil the long awaited comeback of Boeing's cutting-edge aircraft in Japan after an electrical panel fault was reported on a test flight yesterday.

The part was replaced and ANA, the Tokyo-based carrier, will finish plane and pilot tests on schedule following a more than four-month grounding of the carbon-composite aircraft, Yoichi Uchida, an ANA spokesman, said by phone yesterday. The scheduled June 1 restart for commercial 787 flights is unchanged, Mr Uchida said.

ANA, the world's biggest operator of Boeing's 787 Dreamliner, said a switchboard was damaged by heat on a 787 training flight after a nut was not fully tightened.

Engineers found discolouration on a connection on an electrical panel following a flight from Tokyo's Haneda Airport to Sapporo on Japan's northern island of Hokkaido on May 4, a spokesman for ANA said.

The panel, which was not part of the jetliners' battery system, was changed and the plane returned to Tokyo. ANA said the incident did not compromise the safety of the aircraft.

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, the world's second-largest Dreamliner operator, will resume 787 flights the same day.

The 787 Dreamliner was grounded worldwide in January after batteries overheated on jets owned by ANA and Japan Airlines. ANA, which took delivery of its latest Dreamliner on Tuesday, owns 18 of the jets, with JAL operating seven.

Investigators in the United States and Japan have yet to discover what caused the 787's batteries to overheat.

The Dreamliner is safe to fly, even as the cause of the battery meltdowns remains uncertain, Mike Sinnett, the vice president and chief project engineer of the 787 programme, said last month. Stress testing of Chicago-based Boeing's redesigned system showed its steel casing and heat vent reduced battery overheating, he said.

Meanwhile, Kuwait Airways, seeking a return to profit within the next three years, agreed to buy 25 Airbus aircraft comprising 10 A350-900s wide-bodies and 15 short-haul A320neos in a deal worth US$4.4 billion at list price.

The A320s will arrive from 2019, followed a year later by the A350s, the Kuwait Airways chairman, Sami Al Nesif, said yesterday. The carrier, which also secured five options for each model, will lease 22 planes while it awaits the deliveries.

* with agencies