Fire in a single-storey brick-&-mortar house (tile roof on timber),
with allegedly a gypsum-board ceiling (probably 1/4" or 1/8"-inch).

Fire was almost a decade ago, and I've only been recently called in
to contest a fire chief's contention that it must have been accelerated
since flashover (12'x14'-bedroom, double-bed) went to flashover in <10 minutes
(the sole surviving witness claiming that, upon discovering the developing fire
and whilst rushing back & forth with buckets of water, the ceiling had collapsed).