Boeing 787 Dreamliner troubles build
Must have one helluva generator/alternator.
Wonder what the bleed air loss vs HP to turn an generator/alternator relates to fuel efficiency.

Two 259kva starter/generators on each engine and two 225kva starter generators on the APU.
Another good article.
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I have a great deal of experience with Thales hardware. Most is reliable and of good quality. The newer products of theirs (last 10 years technology) is suspect.
NTSB Head Questions Approval of Boeing Dreamliner Battery

Boeing had said its tests showed no evidence such a cascading failure was possible, and assessed that the lithium- ion batteries would produce smoke less than once in 10 million flight hours, Hersman said.
“The 787 fleet has accumulated less than 100,000 flight hours, yet there have been two battery events resulting in smoke less than two weeks apart and on two different aircraft,” she said. “Assumptions used to certify the battery must be reconsidered.”
Investigators and Boeing are trying to determine what caused a battery fire on the JAL plane in Boston and a cockpit warning that spurred an emergency landing in Japan by an All Nippon Airways Co. 787. Those incidents triggered grounding orders worldwide starting Jan. 16.
One Cell

The NTSB has found one cell on the JAL battery overheated as a result of a short-circuit, starting a reaction in other cells that led to the fire, Hersman said. Investigators still are looking at possible causes of the initial short-circuit, including the recharging process, she said.
There was an unexpected drop in the battery voltage to 28 volts from 32 volts, pointing to the failure of one of the battery’s eight cells, she said. Investigators ruled out mechanical damage and external short-circuiting. All battery damage occurred after the short-circuiting began, she said.

Because FAA regulations didn’t cover aspects of the new design, the plane was certified with “special conditions,” including nine that allowed use of the lithium-ion batteries, Hersman said.
Boeing received regulators’ permission to use the batteries in 2007, three years after the FAA barred passenger planes from carrying non-rechargeable versions of that type of battery as cargo because of fire concerns.
All this problem is another case of YUASA S.D.S. (Sudden Death Syndrome). Boeing needs to get another vendor for their batteries and get rid of those Yuasa junk batteries.
Airbus is dropping lith/ion batteries on the A350.
Boeing fucked up.
787 still on the tarmac.
Boeing prepares plan for interim fix for 787

Boeing will propose to regulators as early as this week a short-term fix to bolster the 787's defenses in case of battery fires such as those that have kept the jet grounded for a month.

The interim fix includes a heavy-duty titanium or steel containment box around the battery cells, and high-pressure evacuation tubes that, in the event of a battery fire, would vent any gases to the outside of the jet.

Boeing's approach implicitly acknowledges that four weeks after two batteries overheated -- one catching fire on the ground, the other smoldering in flight -- investigators have still not pinpointed the cause.

But unlike Airbus, which said last week that it will switch to nickel-cadmium main batteries for its forthcoming A350 jet to avoid the possibility of delays, Boeing insists it will stick with the high-energy lithium-ion batteries that provide emergency backup power for the 787.

"Boeing is confident in the safety and reliability of lithium-ion batteries," said spokesman Marc Birtel, and "good progress is being made" in resolving the battery problem.

B) xUT
Even though they say they are sticking with the lith/ion battereies I would not be suprised it they are looking at ni/cads as a fallback plan.
Even though they say they are sticking with the lith/ion battereies I would not be suprised it they are looking at ni/cads as a fallback plan.
The multi-point Boeing plan is thought to cover a phased approach toward a fully modified lithium-ion battery system. The short-term fix focuses on a new containment system for the existing unit, together with added venting ducts for smoke and additional monitors. It is also thought to incorporate another layer of crew procedures to check battery health and status via the engine indication and crew alerting system before, during and after flight.

I see Yuasa is blaming everyone but themselves for their lousy 787 batteries again. They do the same thing when their junky motorcycle batteries short out and leave you stranded in the middle of no where. I hope Boeing has got another vendor lined up, or the 787 will be a hangar queen forever. There is nothing wrong with Lithium ion batteries. Just in this case Boeing picked the worst battery company in the universe to make batteries for the 787.