Hello Chris,Dreamk &sgdbdr,
Another use for Darts was to set on fire Zepplin airships. Incendiary bullets had not had the success expected, and the story developed that the exhausts from the engnes was led into the envelope, surroundig the gasbags with a reduced oxygen atmosphere. This was supposed to be negating the incendisry effect of the bullets.
The solution was to drop darts, which had an expanding support frame, so that the burning dart would be suspended in the rented envelope, where the atmosphere could reach the burning tip.
In the sixties, while working at Smiths Industries, Cricklewood. I found an old blueprint detailing such a dart, designed by Primus Otto Dorer, the then Chief Engineer, around 1915. The by then retired P.O D told me that he had made a sample, and placed it on a table in the drawing room, ready to take to the Navy early nest day. He wa horrified to hear his very young son had woken early, and found him happily playing with the live device! It ws complex and I don't think that it was used. I think Brock designed one that saw service
I still have the blueprint, hidden somewhere in the atic!