Originally Posted by
WillowRun 6-3
Okay, I get that SC's are routine or mostly so in context of rapidly advancing technologies and engineering techniques.
Debateable whether or not the LiON batteries were a new or advancing technology, certainly to an outside observer they look like an extant tech that was new to transport aircraft, and was thought at the time by many to be too risky to use in that context. Now, same can be said of FBW back in the 80s when it made the move from military to civilian transport, but A did a heck of a lot of work on FBW to mitigate risk, and (again, to an outside observer) it isn't clear that B did anything significant to the battery tech to de-risk it.
What still seems like a question worth addressing (and I'll say "why is it worth..." in a moment) is whether the SC for the batteries turned out so badly that
Entirely possible that the SC itself was fine and that the compliance was wanting (cf. MCAS). SC is at
https://www.federalregister.gov/docu...y-installation I believe. Notably it states that:
(2) Design of the lithium ion batteries must preclude the occurrence of self-sustaining, uncontrolled increases in temperature or pressure.
Which evidently wasn't precluded,and also:
(3) No explosive or toxic gases emitted by any lithium ion battery in normal operation, or as the result of any failure of the battery charging system, monitoring system, or battery installation not shown to be extremely remote, may accumulate in hazardous quantities within the airplane.
Which is clearly being addressed by the venting system. The venting system that was added after the in-service failures...