This thread reminds me of a recent observation at one of the local USCG homeports. I was there doing some work on one of the cutters, I will not say any names to protect the innocent.
We were dockside, with a diver in the water working and had a pretty good view of a training session going on for some nonrates down the quay.
This was apparently a training session on how to properly use a flare. The chief teaching the class spent about twenty minutes with his monologue before firing off a parachute flare.
It was a slightly breezy day and after the flare ignited it performed a graceful glide right down on top of one of their dockside picnic cabanas. Where it promptly set the shingle roof on fire.
The group of nonrates rushed into action and one managed to run to the cabana and with some assistance of some of his companions, put out the roof with a fireproof blanket of some kind. (I assume, it could have been his jacket).
I guess even the professionals have problems with flares sometimes.