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Cydrome Leader Cydrome Leader is offline
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Default Update on 787 Battery Problems

wrote:
On Mon, 25 Mar 2013 17:29:29 +0000 (UTC), Cydrome Leader
wrote:

Joe Gwinn wrote:
In article , Larry Jaques
wrote:

On Sun, 24 Mar 2013 14:50:07 -0400, Joe Gwinn
wrote:

I just read the 18 March 2013 issue of Aviation Week. On pages 28-29,
there are two articles on the 787 battery investigation results and
proposed fixes.

What caught my eye, and apparently that of the investigators, was that
there was never an all-up test of the 787 battery charging system with
the actual Yuasa-made production battery. They were tested
independently, but there is no record of them ever being tested
together.

So, they're doing things like our CONgress critters do now, eh?
deep sigh "We need to pass this bill so we can see what's in it."
said Nancy Pugnosy.

Well, the individual companies (for battery and for charger) no doubt
satisfied their respective contracts. It's Boeing that should have
insisted of a full-up test, and it's the FAA that should also have
insisted that Boeing insist.

This reminds me more of the NASA screwup that caused the Hubble to be
nearsighted - there was never a full-up optical test on the ground.
The problem was that they had two null-corrector results. The big
fancy null corrector said the optics were perfect, while the simple
crosscheck corrector said the optics were off. Perkin-Elmer, the
optics house that made the mirrors, offered to do a full up test for
something like $20 million, but NASA declined, and chose to believe the
complex null corrector. Oops.


yet the kodak made mirror which was perfect was left in a warehouse or
something like that.

Anyway, the fixes are basically to isolate the cells better so if one
self-destructs, it cannot take the other cells with it, venting of
smoke overboard, better electrical insulation all around, and a lot of
black-box data recording so they can figure out root cause next time.

Did they ever ask Elon Musk what he had in mind? He offered to fix it
for them gratis.

No, they did not take Elon Musk up on it. Nor would I have, were I in
charge. The air safety crowd that does investigations is very good at
this stuff, and bone-crushingly thorough. SpaceX simply hasn't the
throw weight to compete.

Joe Gwinn


the investigators made by good, but it's clear nobody as boeing knows what
the're doing.

While you can blame subcontractors, it's boeing that sells the planes so
it's their problem for picking jr level, unsupervised suppliers.

It's just weird. Being can design an airplane, but can't put together a
battery and charger themselves?

Boeing didn't design the plane, or build it. That's the problem. The
whole shooting match was contracted out, with final assembly by
Boeing. Everything between "concept" and "final assembly" was
contracted out to the lowest bidder.


somebody had to say this is the final shape and these are the functional
components we need, and that had to have been boeing.

It must be a fascinating process to get everything from various suppliers
to even fit together in the first place.