There has been articles telling that Boeing 787 planes are grounded over safety concerns in USA. The Federal Aviation Administration has ordered U.S. airlines to stop operating the Boeing 787, after a series of battery and fuel system failures have called into question the airworthiness of the newly developed composite aircraft. Japan’s two biggest airlines grounded all their Boeing 787 aircraft for safety checks Wednesday after one was forced to make an emergency landing in the latest blow for the new jet. Here is my collection on what I have found written on the recent Boeing 787 problems.
The 787, known as the Dreamliner, is Boeing’s newest and most technologically advanced jet, and the company is counting heavily on its success. Since its launch 787 plane has been plagued by a series of problems including a battery fire and fuel leaks. There are always teething problems with any new aircraft and airlines often are reluctant to be the launch customer of any new airplanes. You need to ensure safety, and then you also have to get people to feel that the jet is 100 percent safe. The problem here for one of America’s largest manufacturers is enormous. Developing a whole new model of airplane is expensive.
Over the years the demand for electrical power has increased in planes as new technologies such as fly-by-wire (FBW), digital avionics, and in-flight entertainment (IFE) systems are introduced. This is in addition to other power demand increases, such as the on-going change from hydraulic and pneumatic systems to electrically powered systems. Dreamliner 787 uses lots of electrical power for actuators and more, compared to earlier aircraft. Why? That’s easy to answer: in order to reduce weight and get the benefits of electronics and advanced algorithms, much of the conventional hydraulic power and control of the aircraft has been replaced by electrically-based power and control, and with advanced electronics and software, of course. Plus, the airframe is also largely made of up composites for reduced weight, instead of conventional aluminum.
Taking a Peek into Boeing 787 Electrical Power System article tells 787 will generate five times the electrical power than its predecessor (767)! 787 electrical system is 230V system (most other aircraft systems operate at 115V AC or 28V DC). The electrical power generation on board a 787 is 1.4 megawatt. The environmental control system (ECS), anti-ice system and hydraulic system are all electrically driven (making it more efficient than traditional bleed air extraction and air turbines). The electrical system is more critical to the operation of the Dreamliner than on previous Boeing aircrafts. The new electrical system has it’s benefits, but also problems. Boeing Investigates 787 Dreamliners for Electrical Issues. The More Electric Aircraft – Why Aerospace Needs Power Electronics slide set has some slides that give you some details on 787 electrical system. In 787 generator provides variable frequency supply that is directly connected to power bus. Nearly all aircraft loads will require power converters.
These electrical systems require lots of batteries for start-up, backup, and even operation. The preferred rechargeable energy-storage technology for the batteries is based on lithium-based chemistry. This makes sense, since lithium offers much, much higher energy density (by weight and volume) than any other available battery chemistry. Boeing 787 and Lithium Ion battery failure article tells that the 787 is the first airliner to make extensive use of lithium-ion batteries to help power its energy-hungry electrical systems. The batteries charge faster and can be better molded to space-saving shapes compared with other airplane batteries.
So what are the reasons behind the latest problems in 787. Lithium-Ion Batteries Emerge as Possible Culprit in Dreamliner Incidents. All Nippon Airways has ground its fleet of 17 Boeing 787s after an aircraft made an emergency landing following a suspected battery problem. ANA said a cockpit message showed battery problems and a burning smell was detected in the cockpit and the cabin. An inspection of the All Nippon Airways 787 that made an emergency landing in western Japan found that electrolytes, a flammable battery fluid, had leaked from the plane’s main lithium-ion battery. Investigators found burn marks around the damage. Keep in mind what appears to be “the problem” often is just a misleading manifestation of the real problem elsewhere.
The fluid is extremely corrosive, which means it can quickly damage electrical wiring and components. The electrolyte fluid conducts electricity, so as it spreads it can short circuits, interfere with electrical signals and make control of the plane impossible for pilots and ignite fires. Aviation experts said the energetic quality of lithium-ion can be a concern onboard aircraft. “One of the issues with lithium batteries is they get very hot,” Freiwald said. “When they ignite, they can burn so hot that Halon 1301 won’t extinguish a fire.”
We do not yet know what the official cause of the Boeing 787 Lithium-Ion battery breakdown was on the two aircraft until the full investigation has been completed. Proper Lithium-Ion battery charging and safety article have some good advice from experts in the industry that show how critical a good protection scheme is in a critical design such as on a commercial aircraft. Every lithium ion battery pack should have a safety board or IC which monitors the charge and discharge of the pack, and prevents improper conditions. Lithium-ion operates safely within the designated operating voltages; however, the battery becomes unstable if inadvertently charged to a higher than specified voltage. Li-Ion batteries commonly require a constant current, constant voltage (CCCV) type of charging algorithm. The main challenge in charging a Li-Ion battery is to realize the battery’s full capacity without overcharging it, which could result in catastrophic failure. The target charging voltage of a Lithium-Ion cell is 4.2V +/- 0.05V per cell, and the protection circuits should prevent charging above the specified safe voltage. There is very little room for error if you want to use all the capacity, especially when you are charging many cells in series (you need special battery management). Consistent overcharging can cause the plating of metallic Lithium within the cell, which will cause instability, especially if the cell is of lower manufactured quality, and especially if any moisture has been introduced inadvertently during the production stage.
Lithium-ion is not the only battery that is a safety hazard if overcharged. Lead- and nickel-based batteries are also known to melt down and cause fire if improperly handled. Automakers, many of whom use lithium-ion chemistries in hybrids and electric cars, typically operate their batteries with cooling systems. Even with cooling, however, lithium-ion automotive batteries have been known to have problems on rare occasions. Lithium-ion battery energy density is so high that there’s a lot of stored energy in that small volume, and a failure such as an internal short can result in huge current flows and subsequent fires or even explosions.
So we have the typical engineering situation of a tricky tradeoff. We want the benefits of lower weight, greater efficiency, higher energy density, and so on, but we also have to accommodate and anticipate all the implications of the technology that makes it possible. While lithium chemistry has such high density and subsequent danger, just remember that hydrocarbons such as gasoline have far greater energy density than the best batteries, yet we have managed to make that explosive technology into a safe energy-storage medium and power source.
The 787 Dreamliner Scenario: How Data Can Solve Epic Messes article tells that sensors linked to analytics and diagnostic software could help companies like Boeing solve crises more quickly. Following reports of battery failures onboard Boeing’s 787 Dreamliner, the Federal Aviation Administration (FAA) has issued an “emergency airworthiness directive” temporarily grounding the airliners. And at the moment, Boeing has a big data job on its hands: figure out the root of the battery issue—and how that issue might affect the 787’s other critical systems. The incidents did motivate aviation authorities around the world to order stoppage of Boeing 787 flights, however. The FAA also announced it will work with Boeing engineers to conduct a comprehensive review of the 787’s design and manufacture, with an emphasis on the aircraft’s electrical power and distribution systems.
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Tomi Engdahl says:
Trial by fire: Boeing should have chosen a safer type of lithium-ion battery chemistry for its 787
http://www2.electronicproducts.com/Trial_by_fire_Boeing_should_have_chosen_a_safer_type_of_lithium_ion_battery_chemistry_for_its_787-article-newspo01_787_18jan2013-html.aspx
Lux Research say Boeing uses high-energy batteries inherently at risk of thermal runaway, and should switch to an alternate type of lithium-ion battery
Potential cost savings and more demanding electrical loads are pushing airliners like the Boeing 787 towards lithium-ion (Li-ion) batteries. However, according to Lux Research, the type of Li-ion battery chemistry must be carefully chosen and well-managed.
Failure to do so may result in serious safety issues. On January 7, a 787’s Li-ion battery caught fire while the airplane was parked. Then, on January 16, another suspected 787 Li-ion fire forced an emergency landing.
The Li-ion batteries in question are supplied by Japanese battery manufacturer GS Yuasa. Lux Research analyzed the Boeing 787 battery specifications and found the following:
Boeing did not choose the safest battery type. The 787’s batteries use a material known as lithium cobalt oxide (LCO), which imparts excellent energy density. However, there are known LCO safety concerns, most notably that the material does not resist overheating well. Once started, Li-ion fires typically generate oxygen and are very difficult to extinguish
Boeing’s reputation has taken a major hit, and it must invest considerable funds to prove the safety of the aircraft to anxious regulators.
GS Yuasa has felt the ramifications of the widespread attention surrounding the 787, losing over 5% of its stock value in a single day.
Tomi Engdahl says:
Boeing 787 fleet grounded indefinitely as investigators stumped
Short circuit may be culprit for flammable flights
http://www.theregister.co.uk/2013/01/25/boeing_787_ntsb_report/
Boeing’s flagship fleet of 787 Dreamliner aircraft will be grounded for the foreseeable future after a preliminary report from the National Transportation Safety Board (NTSB) said the cause of two battery fires had yet to be found, and that Japanese investigators are similarly baffled.
“One of these events alone is serious; two of them in close proximity, especially in an airplane model with only about 100,000 flight hours, underscores the importance of getting to the root cause of these incidents.”
That’s very bad news for Boeing, which needs to get the issue sorted out before buyers start cancelling orders. Boeing has been in crisis mode
Finding another battery supplier, or a different power source, would be a massive problem since the 787′s batteries are a custom design Boeing outsourced to Japanese manufacturer GS Yuasa.
Much of the 787′s systems were provided by outsourcing partners, a decision Boeing said at the time would result in considerable costs savings.
The old adage of being penny-wise but pound foolish comes to mind.
Tomi Engdahl says:
Were the Boeing 787 Batteries Cooled Properly?
http://www.designnews.com/document.asp?doc_id=257987&cid=NL_Newsletters+-+DN+Daily
The Boeing 787′s high-profile battery fire may have been the result of an engineering double-whammy: an energetic battery chemistry combined with a possibly inadequate cooling system.
Battery experts who spoke to Design News this week said that the 787′s lithium-ion batteries employed a cobalt oxide cathode, which is known to be more prone to overheating than other lithium battery chemistries.
“It’s a no-brainer,” Elton Cairns, a professor of chemical engineering at the University of California and a nationally known battery expert, told us. “If they used a cobalt oxide chemistry, then the battery should use a cooling system.”
“The images I saw indicated that there was no active cooling system and this battery pack has many cells stacked close together,”
787′s 63-lb battery pack is smaller than those of today’s typical electric cars
design voltage of 32V
On January 20, investigators said that the battery did not exceed its prescribed voltage.
Whether or not the battery exceeded its design voltage, however, experts believe a cooling system was critical.
“Not all lithium-ion batteries are created equal,” Cosmin Laslau, a research analyst for Lux Research, told us. “None of them should fail. They are all essentially safe. But in the event of a failure, lithium cobalt oxide would fail earlier than the other types. Chemical bonds in lithium cobalt oxide will release oxygen earlier.” Experts say the release of that oxygen can, in rare cases, lead to fire.
Battery experts who spoke to Design News repeatedly stressed the fact that all types of lithium-ion batteries can be safe and successful, if engineered properly.
M. J. REMEC says:
It is possible that even though YUASA LiCoO2 787 batty was AOK when installed in 787, the ambient temps were (way) outside permissible specs at incident. Second, at the battery current state of charge, the instantaneous current drawn MAY have been so high that Ro, Zo, caused the beginning of thermal runaway. Third, the high-engine-starting current MAY have caused large-enough-metallic particles to separate from batt electrodes to POSSIBLY short the batt internally.
Tomi Engdahl says:
Excerpts from The TAB Battery Book: An In-Depth Guide to Construction, Design, and Use
Battery reliability and safety (Part one)
http://www.edn.com/design/power-management/4405532/Battery-Reliability-and-Safety
Battery reliability and safety (Part two)
http://www.edn.com/design/power-management/4406023/Battery-reliability-and-safety–Part-two-
Tomi Engdahl says:
Tesla CEO: Boeing Batteries Needed Better Cooling
http://www.designnews.com/document.asp?doc_id=258307
Questions about the cooling of the Boeing 787′s batteries came up again this week, as Tesla Motors CEO Elon Musk publicly stated that the plane’s large pack design is a risky one.
“Unfortunately, the pack architecture supplied to Boeing is inherently unsafe,” he wrote in an email to Flightglobal.com. “Large cells without enough space between them to isolate against the cell-to-cell thermal domino effect means it is simply a matter of time before there are more incidents of this nature.”
Musk has tweeted his desire to help Boeing with its battery problems, which included incidents in two Japan Airlines flights and a United flight this month. On Jan. 18, he wrote, “Maybe already under control, but Tesla and SpaceX are happy to help with the 787 lithium ion batteries.”
The issue of battery cooling has been at the forefront of the Boeing story for a week.
“The electrical system that manages the battery is not a complete battery management system,” he said. “In my view, a complete battery management system includes the dispersion of any heat that is generated by the operation of the battery. Just having protective circuits is fine, but it is absolutely insufficient.”
Tomi Engdahl says:
Boeing 787 investigation making progress
http://www.reuters.com/article/2013/02/04/uk-boeing-idUSLNE91301F20130204
U.S. officials on Friday said they are making progress in their investigation of a battery fire on a Boeing Co 787 Dreamliner in Boston
All 50 Boeing 787s remain grounded as authorities in the United States, Japan and France investigate the Boston battery fire on January 7 and a separate battery failure that forced a second 787 to make an emergency landing in Japan a week later.
“Our investigators are moving swiftly and we are making progress,”
The NTSB said an expert from the Department of Energy had joined the investigation, and an NTSB investigator would travel to France on Sunday or Monday with a “battery contactor”, which connects the battery to the planes’ electrical systems, for further tests at the equipment’s manufacturer,
The failure of investigators to identify the root cause of the incidents has sparked concerns that the 787 grounding will last longer, and hit Boeing and the airlines that operate the 787 harder than expected.
Tomi Engdahl says:
Boeing’s Woes Shouldn’t Be an Indictment of Electric Cars
http://www.designnews.com/author.asp?section_id=1395&doc_id=258393
These days, you don’t need to be an engineer to know what a lithium-ion battery is. Half the country now knows that lithium-ion chemistries played a role in fires aboard Boeing’s 787 Dreamliner.
So it’s probably inevitable that much of the public is now making the connection between Boeing’s fires and electric vehicles.
A recent NBC News story asked whether Boeing’s woes would “short-circuit” electric cars.
If all of that is beginning to sound like an indictment of lithium-ion batteries, then that’s a shame.
Yes, it’s true that today’s electric cars and plug-in hybrids use lithium-ion batteries. And it’s true that lithium-ion is more prone to overheating than, say, lead-acid or nickel-metal hydride chemistries. But the term that too often gets left out of these discussions is “engineering.” This is what engineers do. It’s what they’re good at. They take energy sources and make them do work. And if they do their jobs right, then they do it safely.
“No matter how you slice it, a lithium-ion battery, or any high-performance battery, is a package of energy,”
That’s why engineers at General Motors put 144 plates filled with liquid coolant between the lithium-ion cells on the Chevy Volt. It’s why Toyota uses 42 sensors to monitor temperatures of the Prius PHV’s lithium-ion batteries, as well as three fans to cool the cells.
The point is, lithium-ion is energetic, but with proper engineering, not dangerous.
“As long as you have a battery that contains a lot of energy, you’ll never have 100 percent protection against some kind of failure,” Cairns told us. “It’s all a matter of proper design and acceptance of a certain amount of risk.”
Tomi Engdahl says:
Boeing May Resume 787 Dreamliner Flights to Identify Battery Flaw
http://www.wired.com/autopia/2013/02/boeing-resume-787test-flights/
The Federal Aviation Administration is considering letting Boeing resume flight testing the 787 Dreamliner to further investigate a battery problem that has grounded all 50 planes in service worldwide.
The goal is to carefully subject a plane to real-world conditions to evaluate its 63-pound lithium-ion battery and determine what caused batteries to catch fire in incidents known as “thermal runaway.”
The move comes as investigators struggle to determine exactly why a battery caught fire aboard an empty Japan Airlines Dreamliner in Boston and another JAL 787 en route to Tokyo.
No one was injured in any of the fires, which were confined to the electrical bays of each airplane. The Dreamliner uses batteries to power more onboard systems than any airliner in history, and Boeing chose lithium-ion technology — which is found in everything from cellphones to electric vehicles — because it is relatively compact and energy dense.
Tomi Engdahl says:
Battery reliability and safety (Part two)
http://www.edn.com/design/power-management/4406023/Battery-reliability-and-safety–Part-two-
Excerpted from The TAB Battery Book: An In-Depth Guide to Construction, Design, and Use
Misuse may result from overcharging or overdischarging from combining old and new batteries in the same device or batteries with very different capacities.
There are a number of ways batteries could be abused or misused. A certain amount of abuse and misuse tolerance is designed into every battery, but there are limits to the safety mechanisms that can be built into batteries. Battery manufacturers do perform a suite of tests to evaluate the dependability of safety mechanisms, like the strength of the battery packaging, seals, vents, current interrupt devices, and insulators.
Tomi Engdahl says:
Federal Aviation Administration FAA has issued the aircraft manufacturer Boeing a license for model Dreamliner 787 test flights.
“Test flights have an important role when we try to ensure the safety of passengers and bring these machines back in use,” the FAA announced Thursday.
During test flights there is lots of data collection from batteries and electronic control systems. Flights are conducted over uninhabited areas.
NTSB to point out the fact that Boeing estimates the battery fault to occur less frequently than once every 10 million flight hours, but now the damage has already occurred in less than two 100 000 flight hours.
Source: http://www.3t.fi/artikkeli/uutiset/talous/viranomaiset_sallivat_dreamliner_koneiden_koelennot
Tomi Engdahl says:
FAA approves Boeing test flights of grounded 787 Dreamliner
http://news.cnet.com/8301-11386_3-57568300-76/faa-approves-boeing-test-flights-of-grounded-787-dreamliner/
Aircraft builder will be allowed to conduct test flights of the much-hyped aircraft after onboard battery fires led the FAA to ground the planes.
“While our work to determine the cause of the recent battery incidents continues in coordination with appropriate regulatory authorities and investigation agencies, we are confident that 787 is safe to operate for this flight test activity,” the company said in a statement. “As additional precautions, we have implemented additional operating practices for test flights, including a onetime preflight inspection of the batteries, monitoring of specific battery related status messages, and a recurring battery inspection.”
The NTSB said a Boeing risk assessment conducted during the plane’s certification process found that the likelihood of a battery smoke emission event would occur on the 787 less than once in every 10 million flight hours.
Noting that there have already been two incidents in less than 100,000 flight hours, NTSB Chairman Deborah A.P. Hersman said in a statement that “the failure rate was higher than predicted as part of the certification process and the possibility that a short circuit in a single cell could propagate to adjacent cells and result in smoke and fire must be reconsidered.”
Tomi Engdahl says:
“Conventional lithium-ion batteries that use liquefied electrolytes had problems with safety as the film that separates the electrolytes may melt under heat, in which case the positive and negative may come in contact, causing an explosion,”
This potential explosiveness of the materials in lithium-ion batteries — which in the past received attention because of exploding mobile devices — has been in the news again recently in the case of the Boeing 787 Dreamliner, which has had several instances of liquid leaking lithium-ion batteries. The problems have grounded Boeing’s next-generation jumbo jet until they are investigated and resolved.
Source: http://www.designnews.com/author.asp?section_id=1386&doc_id=258305&cid=NL_Newsletters+-+DN+Daily
Tomi Engdahl says:
Trial by fire: Boeing should have chosen a safer type of lithium-ion battery chemistry for its 787
http://www.electronicproducts.com/News/Trial_by_fire_Boeing_should_have_chosen_a_safer_type_of_lithium-ion_battery_chemistry_for_its_787.aspx
Lux Research say Boeing uses high-energy batteries inherently at risk of thermal runaway, and should switch to an alternate type of lithium-ion battery
Boeing did not choose the safest battery type. The 787’s batteries use a material known as lithium cobalt oxide (LCO), which imparts excellent energy density. However, there are known LCO safety concerns, most notably that the material does not resist overheating well.
Tomi Engdahl says:
Dreamliner aircraft investigation continues: Is the culprit dendrite?
Now, the U.S. Accident Investigation Board National Transportation Safety Board (NTBS) examine whether the small fibrous materials, dendrite had effect on the observed Dreamliner battery failures, writes Reuters . Dendrites can be found inside lithium-ion batteries.
Battery experts sauit can cause short short circuits.
NTBS says he studies the “total battery design,” including electrical connections and temperature insulation.
“As part of an ongoing inquiry into finding out whether of the dendrite has relevant part ,” NTBS’s Director of Communications Kelly Nantel said.
The battery problems has already cost tens of millions of euros.
Boeing flew the last weekend of the first test flight after battery problems. Few hours long test flight went according to the company without any problems.
Source: http://www.3t.fi/artikkeli/uutiset/talous/dreamliner_koneiden_tutkinta_jatkuu_onko_syyllinen_dendriitti
Tomi Engdahl says:
Tiny “fibers” may have played role in 787 battery failure, NTSB says
http://www.reuters.com/article/2013/02/12/us-boeing-dreamliner-battery-dendrites-idUSBRE91B08920130212
The U.S. National Transportation Safety Board is investigating whether tiny fiber-like formations, known as dendrites, inside lithium-ion batteries could have played a role in battery failures on two Boeing Co (BA.N) 787 Dreamliners last month.
“As part of our continuing investigation, we are looking at whether dendrites may or may not have been a factor,” Kelly Nantel, director of public affairs for the NTSB, told Reuters in an email.
“We are still considering several potential causes for the short circuiting” in the sixth of eight cells in the battery on the JAL plane, Nantel said.
The NTSB is also looking at “the total design of the battery, including the physical separation of the cells, their electrical interconnections, and their thermal isolation from each other,” she added.
The Japan Transport Safety Board (JTSB) is investigating a second 787 battery incident
Tomi Engdahl says:
NTSB: Short Circuit Caused 787 Battery Fire
The Boeing 787 battery fire in Boston last month was caused by a battery short circuit that led to a thermal runaway condition, the National Transportation Safety Board said.
Source: designnews-mail.com/portal/wts/cemciv2d7EuqeesyjqESDN6i7f3E8b
Tomi Engdahl says:
NTSB: Short Circuit Caused 787 Battery Fire
http://www.designnews.com/document.asp?doc_id=258717
The Boeing 787 battery fire in Boston last month was caused by a battery short circuit that led to a thermal runaway condition, the National Transportation Safety Board (NTSB) has concluded.
NTSB investigators who did forensic analysis of the Boeing battery said the charred components indicated the temperature inside the 63-pound pack had exceeded 500 degrees Fahrenheit during the January 7 incident at Logan Airport. Evidence showed that one of the pack’s eight cells short circuited, causing the temperature to soar.
“Our review of the flight data recorder data shows that the voltage of the battery dropped from a full charge of approximately 32 volts to approximately 28 volts,” said NTSB chairman Deborah Hersman in a press conference on Thursday. “This drop is consistent with the charge voltage of a single cell.”
Boeing said it still has not announced any specific ways to fix the 787 batteries, despite reports in various news media that it has already settled on a fix.
Tomi Engdahl says:
NTSB Press Release
NTSB identifies origin of JAL Boeing 787 battery fire; design, certification and manufacturing processes come under scrutiny
http://www.ntsb.gov/news/2013/130207.html
At a news conference today, NTSB Chairman Deborah A.P. Hersman identified the origin of the Jan. 7 battery fire that occurred on a Japan Airlines 787 parked at Boston Logan Airport, and said that a focus of the investigation will be on the design and certification requirements of the battery system.
“U.S. airlines carry about two million people through the skies safely every day, which has been achieved in large part through design redundancy and layers of defense,” said Hersman. “Our task now is to see if enough – and appropriate – layers of defense and adequate checks were built into the design, certification and manufacturing of this battery.”
After an exhaustive examination of the JAL lithium-ion battery, which was comprised of eight individual cells, investigators determined that the majority of evidence from the flight data recorder and both thermal and mechanical damage pointed to an initiating event in a single cell. That cell showed multiple signs of short circuiting, leading to a thermal runaway condition, which then cascaded to other cells. Charred battery components indicated that the temperature inside the battery case exceeded 500 degrees Fahrenheit.
During the 787 certification process, Boeing studied possible failures that could occur within the battery. Those assessments included the likelihood of particular types of failures occurring, as well as the effects they could have on the battery. In tests to validate these assessments, Boeing found no evidence of cell-to-cell propagation or fire, both of which occurred in the JAL event.
Tomi Engdahl says:
Japanese Probe Finds Miswiring of Boeing 787 Battery
http://tech.slashdot.org/story/13/02/21/007217/japanese-probe-finds-miswiring-of-boeing-787-battery
“A probe into the overheating of a lithium ion battery in an All Nippon Airways Boeing 787 that made an emergency landing found it was improperly wired,”
Tomi Engdahl says:
Japan Probe Finds Miswiring of Boeing 787 Battery
http://business.time.com/2013/02/20/japan-probe-finds-miswiring-of-boeing-787-battery/
TOKYO — A probe into the overheating of a lithium ion battery in an All Nippon Airways Boeing 787 that made an emergency landing found it was improperly wired, Japan’s Transport Ministry said Wednesday.
The Transport Safety Board said in a report that the battery for the aircraft’s auxiliary power unit was incorrectly connected to the main battery that overheated, although a protective valve would have prevented power from the auxiliary unit from causing damage.
Flickering of the plane’s tail and wing lights after it landed and the fact the main battery was switched off led the investigators to conclude there was an abnormal current traveling from the auxiliary power unit due to miswiring.
Tomi Engdahl says:
Runaway Lithium-Ion batteries
http://www.edn.com/electronics-blogs/dave-s-power-trips/4407381/Runaway-Lithium-Ion-batteries
the case for Lithium-Ion (Li-Ion) batteries.
No one expects these batteries to be entertaining by making any kind of sound or flames. I have not spent much time ferreting out information about any accidents involving the batteries. In general, I consider these batteries to be well-behaved, given that they are treated in the manner dictated by the manufacturer. However, they have resurfaced in the news.
For example, there was an event in 2004 where a lithium battery inside a camera exploded and set a passenger seat on fire.
The last big news story for me was the Li-Ion recall in late 2006 when more than eight-million batteries were recalled. There were a few incidents of laptop batteries going into thermal runaway. The problem was traced back to metal shaving from the manufacturing process contaminating the internal battery environment. This caused these batteries to produce an internal short that raised the local battery temperature to the point of thermal runaway.
You may recall a UPS plane crash in 2011 that was thought to have occurred due to a large shipment of Li-Ion batteries onboard.
So what do we know about the 787 Li-Ion battery pack incident? The only definitive information is that the batteries went into thermal runaway. Information is slowly being released. Initially the problem was described as a possible overcharge, but later this was retracted. Recently more information was given about the battery voltage dropping from 32V to 28V unexplainably. This 4V drop would certainly indicate a substantial short of a single cell. If this is the case, there would be enough energy to raise the temperature to thermal runaway.
LiCoO2 often is used when maximum energy density is valued. However, it can be placed into thermal runaway as indicated by the chart. Just before 200°C, this cathode material releases energy that supports a runaway condition. LiFePO4 has virtually no thermal runaway potential, but it also has only about 60 percent of the energy density of LiCoO2. The aviation application has the same issues as many other applications, the demand for high-energy density and nonnegotiable safety.
The big question for the Boeing 787 batteries is how the battery got to a state where thermal runaway became the outcome. This probably is the maddening part of the investigation as this rarely happens.
Tomi Engdahl says:
Boeing 787s to create half a terabyte of data per flight, says Virgin Atlantic
http://www.computerworlduk.com/news/infrastructure/3433595/boeing-787s-create-half-terabyte-of-data-per-flight-says-virgin-atlantic/
Internet of things will create a wide range of opportunities and challenges for airline
Virgin Atlantic is preparing for a significant increase in data as it embraces the internet of things, with a new fleet of highly connected planes each expected to create over half a terabyte of data per flight.
Speaking to Computerworld UK at the Economist Technology Frontiers event, Virgin Atlantic IT director David Bulman said that the airline company is expecting an “explosion” of information generated from a growing number of sources, from employees and customers to cargo containers and planes.
“The internet of things, in a broad sense, is where we are starting to see everything from planes to cargo devices getting connected,” Bulman said. “The latest planes we are getting, the Boeing 787s, are incredibly connected. Literally every piece of that plane has an internet connection, from the engines, to the flaps, to the landing gear.
He continued: “If there is a problem with one of the engines we will know before it lands to make sure that we have the parts there. It is getting to the point where each different part of the plane is telling us what it is doing as the flight is going on.”
This level of operational insight will involve generating large amounts of data from each 787 aircraft, he explained. “We can get upwards of half a terabyte of data from a single flight from all of the different devices which are internet connected,” Bulman said.
With RFID tags to track cargo and, in the future, baggage, large demands are being placed on the airline’s IT infrastructure
Making sense of the big data generated by the internet of things is an ongoing project
“The thing about big data right now is that it is experimental”
“As you move to a big data world you can start to see the trends in that data. You can move towards predicting what will happen with the plane so that you can do maintenance before a problem occurs”
Tomi Engdahl says:
Safety authorities to hold hearings into Boeing 787′s battery woes
Investigators still stumped, fleet still grounded
http://www.theregister.co.uk/2013/03/08/ntsb_investigation_787_fire/
There’s no end in sight for Boeing’s woes with its combustible 787 Dreamliner: the National Transportation Safety Board (NTSB) has released its interim report about a fire on one of the aircraft, and announced that a full investigation into the 787′s batteries will begin next month.
The investigation will focus on the design, certification, and manufacturing processes for the 787′s lithium-ion battery system. Hearings are likely to last for weeks, which is bad news for Boeing, which had no doubt hoped to have this all wrapped up by now. While it waits, all of its 787s remain grounded.
The 48-page interim NTSB report into the 787 fire at Boston’s Logan Airport reports that the problems began after passengers had deplaned and the auxiliary power unit (which keeps electrical systems going when the engines are switched off) began smoking. A ground engineer spotted “caustic smelling” three-inch flames coming from the battery, which he was unable to put out with a fire extinguisher.
Firefighters boarded the plane with thermal cameras and a special clean fire extinguishing agent called Halotron. The cameras showed “a white glow about the size of a softball” coming from the APU and the firefighters squirted 75-100lb of Halotron onto the fire, which reduced – but didn’t quench – the heat.
It’s a major problem for the 787, which relies on the batteries to power a host of control systems installed in place of standard hydraulics, which have been removed to save on weight and increase fuel efficiency.
So while the safety inspectors rub their heads, airlines around the world are left with some very expensive bits of equipment gathering dust and not generating any returns. So far no one is asking Boeing for a refund or cancelling orders – but that could change if the problem isn’t cleared up soon.
Tomi Engdahl says:
Slideshow: ‘Boeing Battery Needs Liquid Cooling’
http://www.designnews.com/document.asp?doc_id=260153&cid=NL_Newsletters+-+DN+Daily&dfpPParams=ind_184,industry_aero,aid_260153&dfpLayout=article
With the root cause of the Boeing 787 battery fire still unclear, one leading battery expert suggested this week that the need for an active cooling system on Dreamliners is even more important.
“This is a step in the right direction,” Elton Cairns, a professor of chemical and biomolecular engineering at the University of California Berkeley, said of Boeing’s reported intention to put more space between the battery’s cells. “But it’s not clear that it’s sufficient.”
Cairns told Design News that an active cooling system — particularly one that uses a liquid coolant to draw heat away from the battery pack — is especially important, given the fact that the failure mechanism in the JAL Boeing 787 fire in January is not fully understood yet. A liquid cooling system — like the kind used in the Chevy Volt battery pack — would be more likely to isolate heat and prevent it from passing from cell to cell, he said.
“The battery did catch fire and you don’t want that to happen under any circumstances,” Cairns said of the 787 incident. “We know for sure that the thermal management system needs to be changed, even if there was an externally caused short circuit.”
According to numerous news reports, Boeing plans to fix its 787 battery by employing additional spacing between the battery’s eight cells to allow for more effective cooling. Boeing reportedly will also use a more fire-resistant container, add sensors for monitoring cell temperatures, and equip the 787 with the ability to vent smoke to the outside. Venting would require that Boeing cut and reinforce holes in the jet’s carbon fiber skin, according to a report in The Wall Street Journal.
After more than a month of intense study of the January battery fire, Boeing is confident that its engineers know the way to fix the faulty lithium-ion battery packs that grounded the 787 Dreamliner fleet in January. The company is now awaiting approval from the Federal Aviation Administration (FAA) to test the new battery design.
Cairns told Design News that the biggest safety concern is the low density of air at high altitudes. There, he said, it might be more difficult to draw heat away from the battery.
“A much safer solution would be to have a liquid-based thermal management system,” he said. “You don’t want the battery to get too cold and you don’t want it to get too hot.” A liquid-based cooling system would not be affected by the density of the surrounding air, he added.
Tomi Engdahl says:
Slideshow: Boeing Underestimated Possibility of Battery Fire
http://www.designnews.com/document.asp?doc_id=260356
Boeing engineers and federal regulators appear to have vastly underestimated the possibility of a lithium-ion battery fire before the 787 Dreamliner was certified.
A fire captain who responded to the Boston fire “reported that the battery was hissing loudly and that liquid was flowing down the sides of the battery case,” the NTSB said in its 48-page report. “He heard a ‘pop’ sound,” and smoke began pouring out of the electronics equipment bay. The captain “received a burn on his neck when the battery, in his words, ‘exploded.’”
The incident occurred while the aircraft was being cleaned after a flight.
That fire was the first of two battery-related incidents for the 787.
The two incidents appear to contradict Boeing’s original functional safety hazard assessment of the 787 electrical power system. That assessment, made before certification, identified two potential hazards pertaining to the aircraft’s main and auxiliary power unit (APU) batteries. The first hazard, “battery vents smoke/fire,” was assessed with an average probability of 1 x 10-9 per flight hour, according to the NTSB report. The probability for the second, “battery vent and/or smoke without fire,” was classified as 1 x 10-7 per flight hour. The assessment now appears to make the events about 20,000 times less likely than what has occurred at this point.
Still, no one as yet knows exactly why the short circuit occurred. Before certification, Boeing’s analysis determined that overcharging was the only failure mode that could cause a cell to vent fire. However, NTSB investigators have said the JAL battery was not overcharged.
Tomi Engdahl says:
Boeing: New Enclosure ‘Keeps Us From Ever Having a Fire’
http://www.designnews.com/document.asp?doc_id=260624&cid=NL_Newsletters+-+DN+Daily
The Boeing Co. took the issue of 787 battery fires head-on last night, definitively declaring that with pending modifications to its lithium-ion battery packs, a “fire can’t begin, develop, or be sustained.”
its engineers have strengthened the design of the packs with a number of technical enhancements. Most important, they said, is the addition of a new enclosure that prevents fires.
“This enclosure keeps us from ever having a fire to begin with. That’s the number one job of this enclosure. It eliminates the possibility of fire.”
The key to preventing fires is to carefully control the amount of available oxygen, Sinnett said.
Sinnett also detailed a number of other fixes for the lithium-ion battery packs. He said engineers wrapped the cells in an electric isolator to make sure they can’t short circuit, tightened nuts on top of the plate that connects the cells, added drain holes to make sure there was a path for moisture to exit, improved the heat resistance of the wire bundles on top of the battery, added heat-resistant sleeves to prevent wire chafing, and employed dielectric isolators above, below, and around the battery. All of those changes are aimed at reducing the possibility of ignition, he said.
To reduce the possibility of overcharging, Boeing engineers also dropped the upper voltage limit of the battery and raised the lower limit.
Boeing has been testing its new battery design for about six weeks and is about one-third of the way through its certification plan.
“We use lead-acid in some of our airplanes. We use ‘ni-cad’ in some of our airplanes. And it’s surprising for many people to know that in the last 10 years, there have been thousands upon thousands of battery failures on commercial airplanes. Many of those have resulted in smoke and fire events.”
Tomi Engdahl says:
Boeing Should Never Say Never
http://www.designnews.com/author.asp?section_id=1395&doc_id=260750&cid=NL_Newsletters+-+DN+Daily&dfpPParams=ind_184,industry_aero,bid_22,aid_260750&dfpLayout=blog
Boeing Co. recently insisted that the new battery design for its 787 Dreamliner “eliminates the possibility of fire.” That may have pacified the average consumer, but it hasn’t made engineers very happy.
In comments to our post on Boeing’s announcement, readers have compared the Dreamliner to the Titanic. They’ve called the lead engineer “cocky,” accused Boeing of a “lack of thinking,” and contended that its management “should be hanging their collective heads in shame.”
hearing how they had successfully managed such immense and complex projects, I was in awe. And I’ve remained in awe ever since.
That’s why it’s so tough now to watch Boeing follow one technical blunder with another. To the public, maybe its recent comments don’t seem like a blunder. After all, saying that its new lithium-ion battery design eliminates the chance of fire is the ultimate vote of confidence, isn’t it? Saying that a fire “can’t begin, develop, or be sustained” is a sign that the problem has been solved, right?
Maybe we’ll never see another lithium-ion battery fire on a Boeing jet. But what’s angering our readers isn’t the results. It’s the approach. Saying “never” isn’t engineering talk. It’s public relations speak, and engineers don’t like public relations speak. They’re trained to deal with realities, not wishful thinking.
Looking at that track record, many engineers are scratching their heads. Engineers are trained to evaluate and mitigate risk. Every day, they build cars, trucks, airplanes, elevators, rockets, medical devices, and other products that have to control a package of energy. Sometimes that package is powerful, but engineers generally find a way to regulate it. In almost every case, they are successful in handling gasoline, rocket fuel, electricity, and, yes, lithium-ion batteries.
But in almost no case do they smack their hands together and say, “The risk is zero.”
it’s much easier to say the risk is zero. That’s what consumers want to believe about every product they touch, anyway. And it’s what they usually believe when something goes wrong and they start phoning lawyers.
So the easy solution is for the company to say “zero.” No risk.
Just don’t tell that to engineers.
Tomi Engdahl says:
Boeing flight-tests redesigned battery for 787 Dreamliner
http://news.cnet.com/8301-11386_3-57576245-76/boeing-flight-tests-redesigned-battery-for-787-dreamliner/
Two-hour test is the first step in returning the aircraft to service after battery fire and heat issues forced the FAA to ground the fleet.
Tomi Engdahl says:
Boeing 787 battery/charging system solutions—Good design or not?
http://www.edn.com/electronics-blogs/powersource/4410051/Boeing-787-battery-charging-system-solutions-Good-design-or-not-
As design engineers, you and I know that the solution is to prevent failure, not contain smoke and fire after the fact.
The Li-ion battery that is used for the Main and the auxiliary power unit (APU) battery contain 8 sealed lithium ion cells that are connected together in series with thermal conductive plates and packaged within an aluminum battery box. The battery also includes the battery monitoring unit (BMU), Hall Effect current sensor (HECS), temperature sensors, internal non-latching contactor, battery failure detection and diode module failure detection (detection of high rate charge current).
These protection circuits are designed to protect against overcharge, over-discharge, overheating, and ensure proper cell balancing.
Each battery is charged by a dedicated Battery Charger Unit (BCU).
The baseline Li-ion battery is a 50 ampere-hour (end-of-life) lithium-ion (Li-ion) chemistry battery. The main and APU batteries are identical, but provide electrical power sources to two distinct functional areas. The nominal voltage of the battery is about 29.6 volts and when it is fully charged, the voltage is 32.2 volts.
Over-charge of a Li-ion cell can result in the cell entering thermal runaway, which could result in the battery cell venting and the generation of smoke and fire.
Each battery charger takes unregulated 28VDC power on its input and converts it to regulated DC power output. The output voltage level varies depending on battery state of charge (SOC), to between 22VDC at 0% SOC and 32.2V when fully charged. For all voltages, the charger current is limited to a maximum output current of 46A.
And now here are the changes being proposed
Boeing, Thales and GS Yuasa have decided to narrow the acceptable level of charge for the battery, both by lowering the highest charge allowed and raising the lower level allowed for discharge.
To better insulate each of the cells in the battery from one another and from the battery box, two kinds of insulation will be added.
One change proposed by Boeing is to seal the batteries in a steel box, which would contain any smoke and fire.
It looks like the designers have done everything possible to prevent another mishap, while not actually knowing what the root-cause was. So by over-designing almost every aspect of the charging, monitoring and battery system design, we trust that the engineers have a solid design in place that should be robust enough to fly.
Tomi Engdahl says:
Dreamliner’s First Flight With New Battery Goes Flawlessly
http://www.wired.com/autopia/2013/03/787-battery-first-flight/
Boeing’s first flight of a 787 Dreamliner using a redesigned lithium-ion battery system was utterly uneventful, which was the best possible outcome.
“There is a series of laboratory, ground and flight tests that have or will take place to complete the certification plan,” Boeing spokesman Marc Birtel told Wired. “We are not providing [more] detail on sequencing of tests.”
kim blond says:
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Tomi Engdahl says:
Lithium-Ion Batteries Overheated in Mitsubishi Vehicles
http://www.designnews.com/document.asp?doc_id=261236&cid=NL_Newsletters+-+DN+Daily
In yet another setback for lithium-ion battery technology, Mitsubishi Motors has acknowledged that it recently had a fire and an overheating incident involving the high-energy batteries.
”A single one of the 80 cells within the battery pack was overheated, melting adjacent cells”
Batteries for both of the vehicles were manufactured by a joint venture involving Mitsubishi and GS Yuasa Corp., the company that made the batteries now being used in the Boeing 787 Dreamliner.
”It’s not clear if there are problems with the batteries from GS Yuasa,”
The lithium-ion batteries used in the Mitsubishi Outlander, as well as the company’s i-MiEV electric car, are believed to use a different chemistry than those employed in the Boeing 787. Both vehicles are said to employ a lithium oxide manganese spinel (LMO) chemistry, whereas Boeing’s units use a more energetic lithium cobalt oxide (LCO) chemistry.
Laslau told us that automakers typically use one of three different lithium-ion chemistries: lithium-iron phosphate (LFP), nickel manganese cobalt (NMC), and LMO. No automakers currently use the chemistry employed by Boeing. ”The auto industry is trying to decide between those three, and determine how they might mix them in a way that combines the best attributes,” Laslau said.
Tomi Engdahl says:
Boeing’s 787 Dreamliner Has Taken Its Battery Certification Flight
http://tech.slashdot.org/story/13/04/06/1818255/boeings-787-dreamliner-has-taken-its-battery-certification-flight
“Boeing just flew the flight it needed to certify the improved battery housing on its 787 Dreamliner, whose battery woes have marred the next generation plane’s launch.”
Tomi Engdahl says:
Boeing’s 787 Dreamliner Has Taken Its Battery Certification Flight
Read more: http://motherboard.vice.com/blog/boeing-has-taken-its-787-dreamliners-battery-certification-flight#ixzz2PkoEGdVk
Follow us: @motherboard on Twitter | motherboardtv on Facebook
Tomi Engdahl says:
Boeing Completes Certification Testing for New 787 Battery System
http://www.prnewswire.com/news-releases/boeing-completes-certification-testing-for-new-787-battery-system-201672091.html
The crew reported that the certification demonstration plan was straightforward and the flight was uneventful.
Boeing will now gather and analyze the data and submit the required materials to the FAA
Tomi Engdahl says:
Boeing Completes Final 787 Battery Test, Awaits FAA Approval
http://www.wired.com/autopia/2013/04/boeing-787-final-battery-flight-test/
Federal Aviation Administration officials flew aboard a Boeing 787 for a test of the airliner’s new battery system that included “normal and non-normal flight conditions” and went off without a hitch.
The “non-normal” flight conditions included “simulating failed engines, generators, pumps and other equipment on the airplane,” Boeing spokesman Marc Birtel said.
Boeing has spent weeks designing and testing improvements to the 63-pound lithium-ion battery after problems arose aboard a Dreamliner at the gate at Logan International Airport and another in flight over Japan. In both cases, the batteries were severely damaged by heat, but damage to the planes was limited to the area immediately surrounding the batteries, one of which is located in the nose of the 787, the other near the middle of the aircraft.
The redesign includes improved separation of individual lithium-ion cells
The new design also houses the battery in a heavy-duty sealed stainless steel box vented directly to the exterior of the fuselage.
Boeing believes the new system eliminates the chance of a battery fire.
Mold inspection NJ says:
I went through about 10 different blogs to find this article, now I think its time to take a nap. =P
Tomi Engdahl says:
787 battery fix approved
Plastic planes still grounded as operators await repair manuals
http://www.theregister.co.uk/2013/04/22/787_battery_fix_approved/
Boeing’s beleaguered 787 is a little closer to flying again after the USA’s Federal Aviation Administration (FAA). approved the plane-makers new battery system plans.
Administration will next issue instructions on how 787 operators should implement the new design. Those instructions will land this week, and the FAA will check to ensure operators follow them before allowing 787s to fly again.
Tomi Engdahl says:
The Dreamliner saga: When your solution is more than just a software patch
http://www.edn.com/electronics-blogs/power-points/4412577/The-Dreamliner-saga–When-your-solution-is-more-than-just-a-software-patch
Boeing and batteries”), and the good news is that Boeing has come up with a solution (aka “fix”) that is approved by the FAA and is being implemented on both in-process and delivered aircraft.
But unlike the convenient world of software patches and downloadable upgrades, this is the real world with serious mechanical, electrical, and thermal consequences.
In short, the solution requires lots of work, as you’d expect. Among the elements are better inter-cell insulation; a stronger, heat/flame resistant containment box; potential venting if needed to outside “just in case;” plus various new sensors and software modifications.
I’ve been following this situation closely, since it simultaneously combines so many engineering and non-engineering disciplines: raw electrical power; power management; safety evaluation; mechanical, thermal, and chemical engineering; aerospace design; politics, media visibility … the list goes on. It has all the elements of a dramatic, reality-based movie in which engineers would be heroes
In the real world of power and aerospace, the fix to many problems involves significant design changes; having to do them in the field adds to the challenge. Just try to imagine the constraints of developing a solution to the problem that can has to be retrofitted to in aircraft already in the field
Yes, we’ve all heard the management-consultant mantra that “change is hard.” In my view, they have no idea how hard it can be, when you are trying to understand, solve, and implement a fix for a problem of this type, on a program this big and visible, with the consequences so large.
Tomi Engdahl says:
How Boeing Rescued the 787
http://stream.wsj.com/story/boeings-787-dreamliner/SS-2-151843/SS-2-216417/
Tomi Engdahl says:
Boeing 787 Dreamliner Finally Resumes Passenger Flights
http://www.wired.com/autopia/2013/04/boeing-787-dreamliner-resumes-passenger-flights/
The Boeing 787 Dreamliner has carried passengers for the first time since a battery problem grounded all 50 planes worldwide, and Boeing says it already has modified the battery systems aboard more than 10 airplanes to correct the problem.
Launch customer All Nippon Airways was first in line for the fix, which includes improved separation of individual lithium-ion cells within the 63-pound battery and installing the battery in a heavy-duty sealed stainless steel box vented directly to the exterior of the fuselage. On Saturday, the airline completed a flight test of the new system with several airline and Boeing executives aboard.
That flight came the same day that Ethiopian Airlines resumed Dreamliner service, carrying a plane full of passengers — including Boeing vice president Randy Tinseth — from Addis Ababa to Nairobi, Kenya.
Federal investigators have questioned the way in which the FAA and Boeing performed the tests. Sinnett testified that, in retrospect, he would have questioned battery maker GS Yuasa more. He says the tests performed, including driving a nail through some lithium-ion cells to create a short circuit, were state of the art but obviously fell short of what could happen during routine use.
senthil says:
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Tomi Engdahl says:
Boeing begins final assembly on 787-9 Dreamliner
http://news.cnet.com/8301-11386_3-57587261-76/boeing-begins-final-assembly-on-787-9-dreamliner/
Newest member of the Dreamliner family will be longer than its predecessor and is expected to be delivered in early 2014.
“Integrating the 787-9 into our production system on time is another clear sign that we are well prepared and well positioned for the work ahead,”
The announcement comes as airlines resume normal service of the 787 Dreamliner, which was grounded for several months following ignition and overheating issues related to the aircraft’s on-board batteries. The airliner returned to the skies last month after the Federal Aviation Administration approved Boeing measures designed to prevent the issues.
highcopyluxury.com says:
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Tomi Engdahl says:
Dreamliner 787 fire problems continue:
Heathrow Dreamliner 787 fire investigation continues
http://www.bbc.co.uk/news/uk-23298349
nvestigators are continuing to try to establish the cause of a fire on a Boeing 787 Dreamliner at Heathrow.
Flights were disrupted on Friday
A team from Boeing is one of several now looking into what caused the fire on the Ethiopian Airlines plane.
Heathrow’s runways were closed for 90 minutes on Friday
Investigators will hope it is not a recurrence of the battery problems that grounded the entire global fleet of 787s for three months earlier this year, said BBC correspondent Richard Lister.
Several aviation experts have suggested that the fire appears to have broken out some distance from the two batteries.
Fifty Dreamliners were grounded in January after malfunctions with the planes’ lithium-ion batteries.
Boeing modified the jets with new batteries and flights resumed in April.
Ethiopian Airlines said smoke was detected from the aircraft after it had been parked at Heathrow for more than eight hours.
kiers says:
Eery, but the Ethiopian Airline plane’s fire is very near to where this diagrame indicates for APU:
http://www.flightglobal.com/news/articles/elon-musk-boeing-787-battery-fundamentally-unsafe-381627/
Tomi says:
Why Is Boeing’s 787 Dreamliner Such A Piece Of Crap?
http://www.popsci.com/technology/article/2013-01/why-boeings-787-dreamliner-such-piece-crap
Amazing new plane keeps catching on fire. Here are the questions you’ve been asking and the answers you need.
Q: What’s wrong with them?
The Dreamliner relies on electrical power much more than its predecessor, the 777. Earlier planes used bleed air, which is super-hot, super-pressurized air taken from within the engine, and used it for all kinds of functions, from de-icing to pressurizing the cabin itself. But in order to cut down on energy use, the 787 relies instead on electrical power for that, from some very powerful lithium ion batteries. Those batteries have of late taken up a new hobby: catching on fire and freaking the hell out of all of us.
Q: Wait a second, lithium ion batteries? Like in hybrid/electric cars? And phones and laptops and a million other things?
A: Well, kinda. There are different kinds of lithium ion batteries, using different chemicals and different reactions, and they behave pretty differently.
Tomi says:
http://787updates.newairplane.com/
Tomi says:
Boeing 787 Returns To Boston After Mechanical Issue, Dreamliner Aircraft Still Having Issues
http://www.huffingtonpost.com/2013/07/19/boeing-787-boston_n_3623219.html
A Japan Airlines flight to Tokyo’s Narita Airport returned to Boston’s Logan Airport on Thursday because of a possible fuel pump issue on the Boeing 787 aircraft.
It’s the latest trouble for the new Dreamliner aircraft after a lithium ion battery problem grounded the fleet in January and a fire erupted on an empty Ethiopian Airlines plane parked at Britain’s Heathrow Airport last week.
Flight 007 returned to Boston “as a standard precautionary measure”
The 787 is the newest and highest-profile plane from Chicago-based Boeing Co.