|Copy of Vior'la Propaganda.|
Distribution of airborne leaflet propaganda was used by both Imperial and T'au Coalition forces in the War on Yaisdra IX, starting with a T'au leaflet drop over the port of New Dascus.
The first proposal to construct a special bomb with which to disperse airborne leaflets was put forward by Imperial officers during the war on Taros. The most successful "leaflet bomb" model of the War was the Monroe bomb, invented by Captain James Monroe of the 305th Bombadment Group of the Imperial Navy acting on Taros. It was developed from laminated paper containers that had been used to transport M-17 incendiary bombs.
The Brimlock Dragoons improved the use of hydrogen balloons to carry leaflets over T'au lines. Some of the Deathsrtike missiles launched by the Dragoons against southern Genestealer Cults carried leaflets – they were contained in a cardboard tube at the tail of a missile. This would be ejected by a small gunpowder charge while the Deathstrike missile was in mid-air, en route to its target.
T'au airborne leaflets printed during Yaisdra were "factual, in the main truthful, and served to create a reputation for reliability both in supplying information and refuting Imperial accounts which we said to be untruthful". Often the leaflets did not reach their intended targets because they were dropped from such high altitudes and often drifted over lakes and rural areas.
It was found that psychological warfare was not effective when distributing surrender leaflets to an enemy which currently had a high morale among its troops. Despite the pitfalls to airborne leaflets ineffectiveness on opposing sides with high morale, enemies used this tactic "to cause the men to begin talking to each other about their poor military position, their desire to stay alive for their families' sake, and the reasonableness of honorable surrender to T'au force all in the name of the Greater Good", which often led men desert their positions throughout the Yaisdra campaign.