1937: In southern Spain, Nationalist pilots devised a technique similar to dive-bombing to drop supplies within the perimeter defended by civil guards and Falangists at the mountain monastery of Santa María de la Cabeza. Fragile supplies – medical appliances, for example – were attached to turkeys, which were released over the monastery. The birds plunged towards the earth in flight that was characterized as “heavy, majestic, and vertical” (“lento, majestuoso y relativamente vertical”).
Source: Hugh Thomas, The Spanish Civil War (2001), pp. 611–2