Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Elon Musk: Boeing 787 battery fundamentally unsafe

flightglobal.com

Post reply on HN
Print view View original

151–160 of 253 posts

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#151

Post by druiid »

gvb wrote: post #46
avelis wrote: post #5

Earlier quoted context omitted.

It would appear that Boeing had a small oversight. Building a plane is not like building a car. There are different requirements. While some requirements overlap there are clear fundamental differences. Now, with that said, it could be that SpaceX and Tesla were allowed to focus more on batteries while Boeing had to improve jet engine efficiency as well as electrical battery usage.

Pedantic: Boeing subcontracted the jet engine efficiency improvements to Rolls-Royce (Trent 1000) and GE (GEnx). http://en.wikipedia.org/wiki/Rolls-Royce_Trent_1000 http://en.wikipedia.org/wiki/General_Electric_GEnx

In this case it is pretty pedantic I'm afraid. Engine subcontracting is pretty standard in aviation. Nearly all of the engine types I can think of are either GE or Rolls-Royce.

It's kind of like Rotax for motorcycles and Snowmobiles... give the designs or specifications to a supplier and have them do all of the heavy lifting.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#152

Post by codex »

I've found that humans are much better at doing than they are at thinking. Humans can generate countless hypotheses and evidence to support those hypotheses, and yet most human theories are flat out wrong. This is why we have the scientific method, which verifies hypothesis with good old fashioned elbow grease.

The real "five whys" question here is: "Why did this battery get through Boeing's (most certainly exhaustive) certification process and win FAA approval?" Boeing is well aware of the risks of lithium ion batteries and must have "proven" to themselves and the FAA that this design was sound through rigorous testing.

I suspect there is an "unknown unknown" here; something so unexpected a test couldn't be fathomed to exercise it. How does one find unknown unknowns? It's a fascinating question.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#153

Post by fhars »

zalzane wrote: post #122
nigelsampson wrote: post #107

Earlier quoted context omitted.

No one ever remembers the predictions you got wrong, just the ones you got right. It's the basis of all punditry.

this is hard to swallow when someone posted a list of half a dozen horribly incorrect technology predictions in this very thread http://news.ycombinator.com/item?id=5138247

Which were all urban legends or misquotes, though.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#154

Post by kragen »

rosser wrote: post #132
kragen wrote: post #128

Earlier quoted context omitted.

You can indeed, and it ignites the gasoline. Gasoline vapors in air have relatively wide explosive limits which can be attained in a wide variety of ways, not only by aerosolization.

Then the multiple times I've seen that done, by multiple different people, all happened with something other than gasoline. I'm not saying it can't happen, and I'm well aware that gasoline vapors are extremely dangerous. I'm just saying that the gas tank in your car isn't "10 times as easy to light up" as the newer, super-energy-dense lithium chemistry based batteries.

Diesel fuel and kerosene are good candidates for the "something other than gasoline". They'll both happily put out a lit match.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#155

Post by yread »

robomartin wrote: post #68

While I can't dispute anything that is being said I think it is unfortunate that this is playing out the way it is. I can't dispute it because there's virtually no reliable publicly-available information on the design of this battery pack. I think it is unbecoming of an engineer or scientist, particularly of prominence, to voice such opinions without access to design data from the source. Before I could even begin to…

I think that talking about the battery pack being inherently unsafe is completely off-topic here. GS Yuasa manufactures batteries for 60 satellites and they haven't had a single failure there http://www.gsyuasa-lp.com/content/gs-yuasa-lithium-ion-batte...

In aviation people usually very thoroughly figure out what went wrong and why and only then suggest fixes. And the fixes are designed by the people who have access to the complete system.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#156

Post by jeltz »

chii wrote: post #137
Spooky23 wrote: post #94

Earlier quoted context omitted.

A smart move would be waiting for the NTSB report instead if assuming that you can divine what is happening with a minimal set of facts. I've had my share of "experts" opine on their imagine root causes of problems based on whatever bullshit they made up while the incident response folks were figuring it out using real data. The problem is, the folks figuring this out aren't talking, because they aren't done. So now…

it makes strategic sense to taint your competitor, if there is no repercussion for doing so, but lots of advantages.

Boeing is not a competitor. If there is any strategy behind this move it is to make the public think it is just Boeing's batteries which are at fault and not lithium batteries in general.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#158

Post by EEGuy »

There is a published picture [1] of one of the failed assemblies next to a normal assembly of the same type, sitting on a forklift pallet. It's easy to gauge the assemblies' physical size and count a minimum of 16 visible cells. Not visible in the photograph are bus bars or power connector.

I don't see a lot of paint discoloration, and a label of some kind is not charred or much discolored.

[1] http://phys.org/news/2013-01-overcharging-batteries-eyed-boe...

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#159

Post by nitrogen »

meh01 wrote: post #30
grinich wrote: post #16

Earlier quoted context omitted.

Not just any MIT prof-- Sadoway is an expert metallurgist and leading researcher on energy storage in batteries. The article is also incorrect: Sadoway is part of the Materials Science Engineering Department. As an aside, his intro chemistry lectures are excellent, entertaining, and available online. http://ocw.mit.edu/courses/materials-science-and-engineering...

Except they're both clueless about battery use in planes.

Is this like that magic ink that patents are printed in that makes inventions something entirely different when you add "in planes" or "on the Internet" to them?

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#160

Post by alan_cx »

From a complete position of ignorance, I have never felt comfortable with these batteries in aeroplanes.

On of my wastes of time is RC modelling. These batteries have been used now for quite some time for power. What we RC people know is that while these batteries have great performance, it very easy to make one blow up if not handled correctly. Enough burned out sheds can testify to this. So, even if the engineers say they they can use them safely, I will always feel nervous of their use. Fine for things like RC models, laptops, phones, real cars even etc, but the plane use, to me, has a question mark against it.

OK, Im 100% sure engineers can make a great defence of their use, but there will always be a nagging doubt for me.

Post reply on HN