[kach22i]

https://www.fabiocampana.com.br/2016/10/barco-deus-nos-guie-do-tre-ap-afunda-em-zona-rural-de-macapa/



https://oldmachinepress.com/2012/09/06/papin-rouilly-gyroptere-gyropter/

The Gyroptere was designed in France from 1911-1914 by Alphonse Papin and Didier Rouilly. Their monocopter was based on the sycamore seed; a single blade extends from the seed to spin the seed and slow its descent as it falls. Though unsuccessful, the machine was the first air-jet helicopter.