Just as Leonardo da Vinci tried to create a flying machine but it only remained on paper, the Military Engineer (yes, there was that before) Conrad Haas, also known as the “Master of Fireworks”, thought of a way to combine fireworks, gunpowder and gun shots. It's not quite what everyone thinks, but he wanted to create something with a propulsion similar to fireworks and at the same time a weapon that could attack from afar causing explosions. Oops, wait a minute, I think I've seen this story before in World War II (see the German V-2).
Let's say he was very pioneering in what he did, he created several categories of rockets, from the single stage to devices with 2 or 3 stages, also called multi-stage. Conrad Haas's rocket consisted of two propulsion stages, of different diameters, one fitted into the other, but there was also a three-stage model, both created in 1529. there was no photography, not even cars, not even balloons, yeah, Hass's rocket wasn't produced and didn't take off, it was just on paper too.
The fuel that propelled the rocket could be ethyl acetate, ammonia, acetic acid, which is derived from vinegar, very normal at that time. He also hears an experiment described in his own book with solid types of fuel, but contrary to what happened with the liquid type, this was possibly carried out experiments but in his book there is nothing that could indicate which type of fuel was used.
In addition, he pioneered the construction of the bell-shaped nose (used to this day), which facilitates air cutting and improves aerodynamics. In addition to incorporating stabilizers in the tail in the form of a delta wing, as known today, discovered in his ignition experiments carried out in 1555 (it's been a while, eh?). In addition, in some of his drawings of multi-stage rockets you can identify a small window at the top, created in 1536, which indicates that space travel was already foreseen at that time, which is very curious since this invention is from before the discoveries of Galileo Galilei, so little they knew even about the solar system.

In his manuscript (Sibiú manuscript) of 450 pages, written between 1529 to 1569 and discovered in 1961 at the University of Bucharest he describes, “But my advice is for peace and not war, leaving the rifles quietly in storage, so that the bullet is not used, the gunpowder is not burned or wet, so the prince keeps his money, the arsenal master his life, Conrad Haas gives advice. “