US federal regulators have responded to a wave of highly-publicised concerns about Boeing 787 electrical system faults by launching a "holistic" review of the programme that will put the twinjet under an unprecedented level of scrutiny barely 15 months after entering service.

The comprehensive review was announced jointly by federal regulators, including Transportation Secretary Ray LaHood and Federal Aviation Administration chief Michael Huerta, and Boeing Commercial Airplanes chief executive Ray Conner.

The review will seek to determine the root causes of the safety and technical incidents plaguing some 787 flights, with a special focus on the aircraft's 1.5MW-capacity electrical system. But federal officials are also being careful to paint the effort as a precautionary measure, lest the travelling public start thinking of the 787 as a safety hazard.

"We believe the 787 is a safe aircraft," says Huerta, whose agency granted the 787 an airworthiness certificate less than 18 months ago.

In the interim, the 787 has accumulated more than 50,000 flights and delivered more than 1 million passengers to their destinations while maintaining dispatch reliability levels that Conner described as "on par" with the 777's introduction in 1995. The 777 posted a 97.9% dispatch reliability record in its first year of service, according to Boeing.

But the 787 also has been linked to several high-profile technical glitches that has prompted two interventions so far by the National Transportation Safety Board. The first such incident involved a contained engine failure in July, which was traced back to a coating problem that was easily fixed. The second incident that aroused the NTSB's concern involved a lithium-ion battery that exploded on a Japan Airlines 787 while on the ground on 7 January, and it remains under investigation.

Several 787s also were grounded briefly in December due to power distribution panel failures that appear to be caused by a batch of faulty circuit boards.

The FAA review, which will assemble in Seattle with a joint team of agency and Boeing engineers, will focus especially on the glitches that arose with the batteries and the power distribution panels.

While the agency usually addresses such issues on a case-by-case basis and releasing airworthiness directives or service bulletins as appropriate, this time the FAA will seek to understand the root causes against the backdrop of Boeing's entire design and manufacturing process, Huerta says.

Still left unclear are the possible regulatory outcomes of the review, and how the FAA's own standards and procedures for approving airworthiness certification will be scrutinised.

Asked for more details, Huerta repeatedly stated that the agency will base its decisions on whatever the data gathered during the review suggests.

Source: Air Transport Intelligence news