Japan Grounds Fleet of Boeing 787s After Emergency Landing 180
hcs_$reboot writes "The Boeing 787 Dreamliner has already occupied some of Slashdot news space recently: FAA to investigate the 787 (Jan 11) or 787 catches fire in Boston (Jan 08). Today (Jan 16 JST) another incident happened that led to Japan grounding its entire 787 fleet until an internal investigation gives more information about the problem. A 787 from ANA had a battery problem and smoke was detected in the electronics. The plane had to make an emergency landing and passengers were evacuated. "
Re:This can't be true (Score:5, Interesting)
No other type of battery has the same capacity/weight ratio though, so either they cut down on the functionality or they increase the weight of the aircraft (and thus reduce its fuel efficiency somewhat). To make it worth using Li-Poly over something else they must really need a hell of a lot of energy storage, otherwise the space and weight saving wouldn't be enough to risk it.
Re:This can't be true (Score:5, Interesting)
Seems more like a QA problem. Energy density is important, but reliability and safety trumps implementation waivers. There's an engineering team that's getting an earful, and rightfully so. Cheers to the airlines for having the guts to ground their fleets; ANA and JAL just went up on my list.
Engineering has been suplanted by cost accountants (Score:5, Interesting)
I had worked as an engineer for approximately 30 years. What I have witnessed has disturbed me.
In the last 10 to 15 years, design decisions that used to be made by engineers have been replaced by cost accountants restricting most decisions of a technical nature and replacing it with "most cost effective solution".
I did some consulting for a small aero engines company about 15 years ago that had a brilliant concept dreamed up by a non-technical MBA executive to start building aero engines for small aircraft based on race car engines. Reasoning for that is because they are high performance engines. Well d'ohhh that is not what you want in an aero engine, you want reliability & safety as the most important factors. Race car engines need to be rebuilt after every race. Not a desirable attribute for an aero engine.
Needless to say extensive testing which I was involved with proved that this idea was half baked and it failed. Problem was executive management freaked and were cursing the engineers for destroying their "brilliant idea" and acted in a savage manner to the staff by trashing many of them.
In many aerospace companies, I have had been involved with have pushed out most experienced staff in favour of young and cheap staff. If I was to guess, I suspect Boeing has done the same thing. I have heard from many experienced colleagues that old technical problems that were resolved decades ago in the aerospace industry are re-emerging due to in-experienced staff and loss of knowledge.
This shift I suspect contributes in part to many of the issues being experienced in the Dreamliner.
my two cents
Re:This can't be true (Score:5, Interesting)
No, that's not why.
The reason is that lithium fires happen fairly easily, and the fire extinguishing systems aboard aircraft are not all that effective against such fires.
Several FAA bulletins have reported that "The current fire suppression agent, Halon 1301, found in class C cargo compartments is inefficient in controlling a lithium metal cell fire." Yet halon is just about all they have on board other than water.
See Slide 7: http://www.777cheatsheets.com/resources/Lithium_Battery.pdf [777cheatsheets.com]
See Page 9: http://www.fire.tc.faa.gov/pdf/04-26.pdf [faa.gov]
Tests were conducted using 4, 8, 16, and 32 CR2 batteries, the 10.75 fire pan, and 220 ml of
1-propanol. In each case, the results were identical. Discharging the halon prior to battery
ignition resulted in the extinguishment of the 1-propanol fire and no battery involvement.
However, discharging the halon after only one battery was ignited had no effect on stopping the
propagation of the battery fire to adjacent batteries. The halon extinguished the 1-propanol fire
immediately but had no effect on the lithium fire with the exception of turning the normally
white sparks bright red.
The color change of the lithium sparks indicated that a reaction was occurring between the
lithium and the Halon 1301. This reaction had no effect on the fire progression, neither
hindering nor promoting the spread of the battery fire. The vented electrolyte fires, normally
pale red in color, turned bright red when exposed to Halon 1301.