The Federal Aviation Administration issued a safety directive on April 30, 2015, indicating a technical software glitch with Boeing's 787 Dreamliners that can trigger the jet's power generators to go into "fail safe" mode and cut power to the plane. File Photo: UPI/Boeing | License Photo
SEATTLE, May 2 (UPI) -- Aerospace giant Boeing has discovered yet another technical problem with its 787 Dreamliner -- and this one could rob the aircraft of its power at 35,000 feet, the Federal Aviation Administration said.
According to the FAA, Boeing discovered the glitch during routine testing. Apparently, software installed on the 787 triggers the glitch if the aircraft is connected to onboard or ground power for at least 248 continuous days, the FAA report said.
The Seattle Post-Intelligencer and Wall Street Journal reported the FAA's safety directive concerning the software Friday.
While that might seem like a long period of time to have a commercial jet connected to power, the 787's software takes such a long time to boot up each time that some airlines may be tempted to keep it connected, experts say -- kind of like how many people never turn their laptops or PCs off because it's simply more convenient to leave them running continuously.
If the Dreamliner isn't powered down regularly, the software can push all four of the plane's main generator control units into "fail safe" mode -- which can cut off the jetliner's entire electrical system, no matter whether it's parked on the tarmac or flying at 35,000 feet over the Pacific Ocean. And such a loss in power could rob pilots of their ability to fly the jet.
If that scenario unfolded, the jet would momentarily resort to battery power and deploy a ram-air turbine -- a fan-like generator that uses outside air, like a windmill, to create a small amount of emergency power.
The 787 is the most power-thirsty commercial jetliner in existence -- as it uses twice as much electricity as the Airbus A-380, the largest jetliner in the world, the Journal report said.
The FAA safety directive instructs all U.S. 787 operators to power down the aircraft's systems at regular periodic intervals to prevent the glitch from occurring. Boeing said powering down the electrical systems of its aircraft is part of regular maintenance, and just last week it encouraged carriers to voluntarily power down the systems at least every four months.
The directive applies to about two dozen 787s are operated by U.S. carriers, but foreign carriers will likely also heed the agency's warning and apply the safety measure to the other 230 Dreamliners flying around the world.
Boeing said it will issue a software update to correct the glitch later this year.
For the 787, which entered commercial service in October 2011, this new headache is the latest in a long line of technical problems that have dogged the aircraft since its introduction.
In 2013, the U.S. National Transportation Safety Board opened a safety inquiry after multiple reports of a fuel leak and one report involving electrical wiring. That same month, the FAA officially grounded all 787 airliners due to a potential fire hazard with its battery system -- the first time the agency removed any aircraft model from flight since 1979.
At the center of the 787's grounding was overheating of its lithium ion batteries made of lithium cobalt oxide. The FAA allowed 787 flights to resume in April 2013 after Boeing redesigned the battery system.
Later that same year, a Norwegian carrier removed a 787 from its operations fleet because it said the plane had broke down on six different occasions.