In an unusual high-priority review, the Federal Aviation Administration said it would focus on how the 787 was designed, manufactured and assembled and would examine critical electrical systems as well as other quality-control issues.

“We are concerned about recent events involving the Boeing 787,” Ray LaHood, the transportation secretary, said during a press conference in Washington. “We will look for the root causes of the recent events and do everything we can to ensure these events don’t happen again.”

Mr. LaHood said the F.A.A. had already spent 200,000 hours to certify the plane before it went into service.

The administrator of the F.A.A., Michael P. Huerta, said the review would focus on the electrical systems of the airplane, including the batteries and power distribution systems, and how they interact with each other.

Raymond L. Conner, the head of Boeing’s commercial airplane division, repeated at the press conference that Boeing had complete confidence in the 787, the first new airplane to be certified in the United States in more than 15 years.

“Every new commercial airplane has issues when it enters service,” Mr. Conner said.

The review, however, will not require the grounding of the 787 fleet, officials said. Boeing has delivered 50 of the airplanes since the first commercial flight in November 2011 and has received orders for more than 800. Eight airlines now fly the 787 – All Nippon Airways and Japan Airlines in Japan, Air India, Ethiopian Airlines, Chile’s LAN Airlines, Poland’s LOT, Qatar Airways and United Airlines.

It is uncommon for the F.A.A. to open a review of an airplane it has already certified, but it points to increased concern by regulators.

A Boeing spokesman, Marc Birtel, declined to comment on any review on Thursday evening. But he said Boeing was working actively with the F.A.A. to understand and address “introductory issues” that might come up with the new aircraft.

“While we take each issue seriously, nothing we’ve seen in service causes us to doubt the capabilities of the airplane,” he said.

The review comes amid an investigation by the National Transportation Safety Board into why a battery pack caught fire in a parked 787 at Logan International Airport in Boston on Monday. The fire occurred in a Japan Airlines plane from Tokyo after the passengers and crew had left the plane.

The battery, which powers the auxiliary power unit used when the plane is on the ground, sustained “severe fire damage,” according to the safety board.

But with the current focus on the 787’s problems, every incident, however small, is getting extra attention. Earlier on Friday, All Nippon Airlines of Japan reported cracks in the cockpit window of a 787 Dreamliner heading from Tokyo to Matsuyama, the third time that cracks had appeared in the windshield of one of the 17 787s operated by the airline.

The cracks were on the outermost of five layers that compose the cockpit windshield and did not endanger the aircraft, said Megumi Tezuka, a company spokeswoman.

Moreover, she said, cracks of this kind are not unique to the 787 Dreamliner; cracks have appeared in other aircraft types operated by All Nippon from time to time.

“We do not see this as a sign of a fundamental problem” with the aircraft, Ms. Tezuka said.

A bigger concern to investigators would be problems in the plane’s electric systems. The 787, which make extensive use of lightweight carbon composites, relies more on electric systems than previous generations of airplanes. Electrical systems, not mechanical ones, operate hydraulic pumps, de-ice the wings, pressurize the cabin and handle other tasks. The plane also has electric brakes instead of hydraulic ones.

This electric architecture helps cut energy consumption and makes the aircraft more efficient to operate.

In a move to quell the damage to the plane’s reputation, Boeing on Wednesday defended its program and said it stood by its engineering and design choices, including the use of lithium-ion batteries such as the one that apparently caught fire.

Boeing pointed out that the plane had multiple layers of redundant systems and emphasized that any new plane program suffered from glitches in its first few years of production.

So far, airlines that operate the plane have stood by Boeing. After years of production delays, airlines have been eager to fly an airplane that promises significant fuel savings.

This week’s events followed incidents with the plane last month. In December, the F.A.A. ordered inspections of fuel line connectors on all 787s, warning of a risk of fuel leaks and fires. That same day, a United Airlines 787 flying from Houston to Newark was diverted to New Orleans after one of its six electric generators failed in midflight.

Boeing said this week that those problems were not related to the fire incident in Boston. It traced the problem on the United flight to a defective electric panel. It added that the 787 proved during testing that it could fly for more than five hours with just one of its six electrical generators.

Some safety experts agreed that the problems with the 787 pointed more to teething problems than structural faults. But the issues are still an embarrassment for Boeing’s flagship program. The plane maker has said it expects to sell 5,000 787s in the next 20 years.

In a separate matter, Japan Airlines said that an incident on Tuesday involving a fuel leak on a 787 was because one of four fuel valves connecting two tanks had been left open. This caused fuel to flow into a surge tank near the wing tip and out a vent. The plane was towed back to its gate but eventually left Boston for Tokyo after a delay of nearly four hours.

Bettina Wassener contributed reporting from Hong Kong.

Article source: http://www.nytimes.com/2013/01/12/business/faa-to-begin-a-review-of-boeing-787s.html?partner=rss&emc=rss