After smoke erupted from the lithium-ion battery pack aboard one Boeing 787 Dreamliner, and fire in another, the Federal Aviation Administration [FAA] grounded the whole fleet.
After weeks of testing though, neither FAA investigators nor Boeing engineers have been able to determine the cause of the smoke and fire in the Boeing 787 Dreamliner’s battery. Boeing’s fix, a new stainless steel battery box, some say, will just contain a fire.
Think for just a moment though, what does a fire need in order to start? Fuel, heat, and oxygen. Now, the stainless steel battery box isn’t hermetically sealed, but it is closed off enough from the atmosphere, Boeing engineers say, to prevent a fire from occurring.
The fuel in this case is the electrolyte. Inside the steel battery box, in the absence of free-moving oxygen, the electrolyte can’t ignite. The only reason for electrolyte to be venting, a runaway thermal event, is if the battery is overcharging. Engineers say that, so far, none of the Boeing 787 Dreamliners have had any problems overcharging. Still, the new battery box is also designed to reroute overheated electrolyte and vapors through a titanium tube venting outside the plane.
The only problem with this solution is weight. Granted, on a vehicle that maxes out at 550,000lbs, the additional 150lb stainless steel battery box on the Boeing 787 Dreamliner doesn’t seem like a problem. The rest of the engineering and design of the plane, using lightweight composite materials to increase the capacity as well as fuel economy of the new craft. The addition of an extra 150lb may fly in the face of the lightweight and economical, but I don’t think that anyone can make the case for a less-safe aircraft.
The investigating authority here is NTSB. Here and in Japan, they’re not impressed with the media blitz, the opinion engineering, and least of all the engineering.
RolandDelhomme it does seem like a band-aid, but then, what would be the solution? sealed lead acid batteries can explode just as easily as lithium ion batteries can burn. go back to half-full fuel tank explosions, and what was the solution? top them off with inert nitrogen. if the batteries can burn, seal them up.
i think maybe the thing that gets me is the fact they’re not sure what went wrong with the dreamliners that did experience the problem. i just hope they’re not pushing too fast just to keep from losing money on a grounded fleet.
bnjroo RolandDelhomme Most folks don’t have access to test pilots, engineers from the 787 program, and a host of technical experts from NASA, DoD and far flung corners of aerospace, or battery researchers; so you do not have and will not get the inside line from folks who witnessed the explosion and fire at Boeing supplier Securaplane, which occured during tests of their charging system for the 787. You
RolandDelhomme “you…will not get the inside line” true enough. hopefully everything is addressed before it costs someone’s life.
Maybe the engineers are reassured, but what about the passengers who pay the engineers’ salaries?
Chris Chatteris i dunno, i still try to forget that i’m in a flying brick held aloft by a little bit of negative air pressure, and that’s in any plane i ride in.