ROCKETS
Introduction:

Figure 1.1 www.teachengineering.org

Figure 1.1 www.teachengineering.org

Man has often looked up and wished to fly among the clouds. Only recently though, has mankind thought of pushing past the known world, past the atmosphere and into the beyond. This can be achieved with the use of a rocket, which is “a cylindrical projectile that can be propelled to a great height or distance by the combustion of its contents and the backward ejection of waste gases.” (Oxford Dictionary). Examples of rockets include fireworks, military projectiles and most importantly, spacecrafts.
Rockets are the pinnacle of human ingenuity, the origins of which extend thousands of years back. Where rockets were first invented is unclear, but the culture with the most substantial history using projectiles were the ancient Chinese. In the first century A.D, records show that Chinese chemists had created a basic gunpowder containing saltpetre, sulphur and charcoal dust. The use of this explosive powder was then applied to create many of the ancient Chinese weapons such as cannons and bombs. At some point the ancient Chinese must have filled bamboo tubes and attached them to sticks, launching them into the air with bows, creating the first real rocket.

Figure 1.2
The first liquid fuelled rocket en.wikipedia.org

Figure 1.2
The first liquid fuelled rocket en.wikipedia.org
Although science was in a primitive form at that stage, the ancient Chinese would have had a basic grasp on the concept of aerodynamics, realising at some stage that a flat faced projectile does not travel as fast or efficiently as a rocket with a pointed nose. This was when the nose cone for the rocket was created, reducing drag dramatically. Figure 1.1 shows what two types of the primitive rockets fired would have looked like.
The use of rockets slowly spread throughout Asia and Europe and by the 18th century the power of rockets found its way to India. At this point in time the Indians were using rockets as weapons of war that helped win battles on separate occasions against the British armies, further spreading the rocket’s popularity to other cultures.
By the 20th century an American, Robert H. Goddard, wanted to further the capabilities of a rocket by using liquid fuel. On March 26, 1926 he successfully launched a liquid propelled rocket seen in Figure 1.2, which was fuelled by gasoline and liquid oxygen 15 feet in the air. Although unimpressive at the time, it sparked a new era for rocket earning him the title the father of modern rocketry.
In 1954, model rockets were discovered by a man named Orville Carlisle who was at the time a pyrotechnics expert. Mr Carlisle then went on to make a business with Harry Stine, where the business was named Model Missiles Inc. Stine then went on to enlist the help of Vernon Estes and the two went into business together. Business mishaps then saw Mr Estes split from the partnership and create Estes Industries in 1958. When rocket enthusiasts began making their own model rockets after the launch of the Soviet Union’s Sputnik, there were many injuries. This lead to Stine and Estes collaborating and creating the NAR Model Rocket Safety Codes.

Parts of a model rocket.

Parts of a model rocket.

Figure 1.3

Figure 1.3
The model rocket has very similar stages to real rockets, expect for the recovery phase. A model has six stages from lift-off to landing. From launch the rocket powers up into the air with the assistance of a launch rail. When it runs out of fuel it enters a coasting stage where it reaches apogee. Due to no thrust, the power of gravity begins to bring the rocket down to earth. The delay charge is slowly burning and eventually and ejection charge is ignited, pushing the parachute outwards. The recovery process is now in effect.
Model rockets consist of various components that are fundamental for large scale rockets. The basic rocket has a propellant (engine), the rocket body and a