A Comparison of Different Rocket Engine Cycles Throughout the Years


Throughout history, humans have had an insatiable desire to understand the world around them, including the stars. The science of rocketry has been developing for centuries, even predating our current era. Today’s rockets are the result of numerous experiments and the combination of many different areas of engineering. Few things can withstand the extreme conditions that rockets must endure, including the intense loads during launch and drastic temperature changes caused by cryogenic components and combustion chambers. Successful launches depend heavily on well-informed design decisions. The complexity and interdependence of the systems that must work together seamlessly in rocket design are unparalleled by any other engineering discipline. It is no coincidence that they say “rocket science” when it comes to something incredibly complex. Figure 1 displays numerous advanced rocketry systems over several decades.


Different Rocket
Figure 1 – Different Rocket Types. Source

Rocketry’s origins trace back to ancient China, where the first rockets were created around 100 AD. These early rockets were used during religious celebrations and produced colorful sparks, smoke, and explosions using gunpowder and bamboo tubes that were closed on one end. The first recorded use of rockets in warfare occurred during the Battle of Kai-Keng in 1232, where the Chinese used a primitive solid-fuel rocket to repel the Mongols. The rocket consisted of a closed tube filled with gunpowder attached to a long stick. Ignition of the gunpowder increased pressure inside the empty tube, and the hot gas and smoke had to escape through the open end. By the law of conservation of momentum, this creates thrust to propel the rocket towards the closed end of the tube, with the long rod as a primitive control system. Read More