Conrad Haas

Conrad Haas (1509 to 1576) was a military engineer of the sixteenth century, described by the source as Austrian or Transylvanian Saxon, who is remembered as an early pioneer of rocket propulsion. He is thought to have been born near Vienna and served as arsenal master (Zeugwart) of the imperial Habsburg army under Ferdinand I. In 1551 Stephen Bathory, grand prince of Transylvania, invited him to Hermannstadt, now Sibiu in Romania, where he worked as a weapons engineer and also taught at Klausenburg, now Cluj-Napoca. His surviving German-language treatise, found in the Sibiu public records in 1961, combines fireworks and weapons technology and treats the theory of motion of multi-stage rockets, liquid fuel mixtures, delta-shaped fins and bell-shaped nozzles. His designs include a three-stage rocket and a manned rocket. Before the manuscript came to light, the first description of a three-stage rocket was credited to Casimir Siemienowicz in 1650. Haas ended his rocketry chapter with a plea for peace over war.