Boeing Co. executives said it was business-as-usual despite the crisis surrounding its 787 Dreamliner, though airlines world-wide made preparations for an extended grounding of the aircraft.
Investigators have yet to pinpoint the cause of electrical problems that triggered battery incidents on two Dreamliners, and Boeing said Wednesday it couldn't give a time frame for when the plane would be cleared to fly. The Chicago-based company continues to produce 787s, but has halted deliveries, forcing future and current operators to use contingency plans.
"I'm confident we'll identify the root cause," Boeing Chief Executive Jim McNerney said on a conference call Wednesday after the company reported a 30% drop in fourth-quarter profit.
Boeing also issued a revenue forecast for this year that fell short of analysts' expectations. The outlook was based on delivering more than 60 Dreamliners this year. Boeing predicted no "significant" impact from the 787 grounding but said that could change.
The delivery halt could create problems for 787 customers, however.
"We are discussing various scenarios for an extended grounding," said Marek Klucinski, a spokesman for LOT Polish Airlines SA, the European launch customer for the jet. The carrier has two 787s and had expected to receive another three by the end of March. But Mr. Klucinski said the delivery dates were unclear. In response, the airline will continue using older Boeing 767s for its routes to Chicago, New York, Toronto and Beijing.
Other carriers have been planning to use the Dreamliner for expansion. Norwegian Air Shuttle ASA, which operates smaller jets, has been hoping to use the aircraft for a push into long-distance markets starting in May.
Mr. McNerney played down reports that 787s had a succession of battery problems before the two incidents that led to the fleet's grounding. Japan Airlines Co. and All Nippon Airways Co., the two biggest Dreamliner customers, said malfunctions had forced them to replace batteries earlier than expected.
ANA said it had replaced 10 of the lithium-ion batteries that are used to start the engines and provide auxiliary power, largely because of problems holding charges or providing sufficient power. The airline received its first 787 in September 2011 and now has 17. The ANA battery replacements previously were reported by the New York Times.
JAL, which has seven Dreamliners, said it replaced some of its planes' batteries and still was investigating the cause.
Mr. McNerney said the replacement rate for batteries was "slightly higher" than the company initially projected, with changes performed for "maintenance reasons."
He said investigators world-wide have nearly "every expert in the world looking at this" and that the probes continued to make progress. But, he said later, "we have no idea yet" what caused the batteries to burn.
Boeing executives said the investigations hadn't derailed efforts to increase 787 production this year. Meanwhile, the development of a revamped 737 remained on track for 2017, and the company is completing details to offer airlines an improved version of its 777 jet, Boeing said.
Boeing's shares rose 94 cents, or 1.3%, to $74.59 at 4 p.m. on the New York Stock Exchange.
The company last year regained its crown as the world's largest producer of jets, topping the Airbus unit of European Aeronautic Defence & Space Co. Boeing projected that deliveries this year will rise to a record of between 635 and 645 aircraft from 601 last year as it boosts production of the single-aisle 737 and twin-aisle 777.
Doug Harned, an aerospace analyst for Buckingham Research, said in a note to clients that the delivery forecast was "disappointing." It is unlikely that faster production would be sustained throughout the 787's supply chain as the company moved to begin assembly of a larger Dreamliner in the second half, he said.
Boeing projected earning between $5 and $5.20 a share this year on revenue of between $82 billion and $85 billion.
The company reported fourth-quarter profit of $978 million, or $1.28 a share, compared with $1.39 billion, or $1.84 a share, a year earlier. Revenue increased 14% to $22.3 billion.
Boeing's backlog of commercial, defense and space products rose to a record $390 billion at the end of last year.
Commercial-aircraft revenue rose 29% in the fourth quarter as deliveries increased. The segment's operating earnings increased 29%.
Revenue from Boeing's defense unit fell 1.5%, while operating earnings dropped 13%. The defense business has been under pressure because of uncertainty over the next round of Pentagon spending cuts.
Yoshio Takahashi, Yoree Koh and Daniel Michaels contributed to this article.
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