The 2013 version of the IATA dangerous goods handling booklet introduced the new Emergency Response Guide code Z for Lithium type battereis. It sates something like (from memory) "Aircraft fire extinguishing systems may not extinguish this fire. Consider an immediate landing". That means now - it dosen't say "As soon a possible" at the nearest suitable airfield. That means NOW! On a highway, in a field, on a lake - or if half way across an ocean - ditch.
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