This article is obviously just a basic introduction to model rocketry. With the Carlisle brothers’ development of the pre-packaged model rocket engine, this is a hobby that can be safely enjoyed by all. I encourage you to get out there and launch your first rocket. Once you do, you’ll be hooked.
If you’re interested in becoming a model rocket enthusiast, you’ll probably want to learn a little bit about the history and workings of the model rocket. This fun hobby can provide years of entertainment and education for you and your family.
Who Invented the Model Rocket Engine?
The modern model rocket engine was created in 1954 by Orville and Robert Carlisle. Orville was a pyrotechnics expert and his brother, Robert, was a model airplane hobbyist. Although small rockets had been designed in previous years by scientists for research purposes, the Carlisle brothers were the first to develop the modern model rocket for the amateur market. Up until that time, many young rocket enthusiasts had been injured (or even killed) trying to create their own model rocket engines. The development of the pre-packaged engine changed the hobby from one that had inherent dangers to one that was safe. It also made rocketry an affordable hobby. The current price for model rocket engines is about $5 for a pack of three engines at local hobby and toy stores.
Parts of the Model Rocket Engine
Most model rockets have pre-manufactured single-use engines. These have become popular because they allow people to fly their model rockets without having to handle the dangerous propellants. The engine consists of the casing (typically paper or lightweight wood) with a clay or ceramic nozzle at one end and a clay end cap at the other end. Between the nozzle and the end cap are three different charges. The Propellant Charge is what gets your model rocket off the ground and into the air. Once this charge has burned off, your rocket will have reached a sub-atmospheric altitude (usually between 1,000 and 1,500 feet). The first charge will burn through and ignite the second charge or Delay Charge during the coasting phase of the rocket’s flight. During this phase, the delay charge emits smoke, enabling you to spot the rocket in the sky. The final phase, the Ejection Charge, activates the recovery system for the model rocket. The ejection charge produces a small explosion which ejects the nose cone and deploys the parachute for recovery of the rocket. used engines
Model Rocket Performance
How fast the rocket travels, how high it ascends, and how far it goes depends on the type of model rocket engine used. Model rocket engines are not all the same. The weight of the case, the amount of propellant or the pattern of the burn, and the length of coasting time for the delay charge all affect the way the rocket will perform.
When purchasing model rocket engines, you will notice that each engine is given a number. The format for the types of engines is the same. It is letter number-number (example C6-4). The letter indicates the rocket engine’s total impulse range (with A being the lowest and O being the highest). This range is defined in newton-seconds, which is a measure of momentum. The first number indicates the engine’s average thrust (measured in newtons). If you have a heavier rocket, you should use an engine with a higher thrust. The second number indicates the length (in seconds) of the delay charge phase. In our example engine, C6-4, the delay charge would burn for four seconds. It’s important to know the length of the coasting phase of the flight so you don’t eject the parachute while the rocket is still ascending, or you don’t eject the parachute too close to the ground on the descent