These flying machines created by Daniel Agdag make me think of those designed by Leonardo Da Vinci in the 15th century. The difference is that Leonardo based his designs in precise calculations while Daniel builds his spectacular cardboard sculptures guided only by his intuition, with no previous sketching.
Daniel Agdad is an Australian based artist. His collection of imaginative flying machines is called The Principles of the Aerodynamic.
All this work is made from cardboard ~ boxboard to be precise. It is cut into intricate pieces using a surgical scalpel and assembled intuitively by hand using a plain, well-known brand of wood glue without detailed plans or drawings. The process is akin to sketching with cardboard.