This photo purportedly shows a British military aeroplane dropping leaflets on the streets of Coventry in early December 1917. I suspect it's a fake, a composite, or else it's a bit odd that nobody seems to have noticed all that horsepower roaring just overhead.1 But the event it shows did happen. According to the Daily Mirror,
A considerable number of aeroplanes flew over Coventry yesterday [2 December 1917] at low altitudes, distributing a quantity of literature pointing out the necessity for an increase in aeroplane production.2
A local paper, the Midland Daily Telegraph, provided more detail:
Throughout Sunday a fleet of aeroplanes hovered the city distributing profuse showers of handbills pointing out the vital need for an increase in aeroplane production [...] The doings of the aviators were watched with great interest, and there were frequently exciting scrambles amongst the crowds for the messages which came floating into the streets and gardens of the city.3
So, what was going on?