Principles of Rocketry

Gareth White

School of Operations and Information Management

UWE Business School

Content

• What makes a “good” rocket.

• Main principles:– Centre of gravity– Centre of pressure– Stability

A “Good” Rocket

Launch

Powered flight

Coasting flight

Apogee

Parachute decent

“Gentle” landing

A “Bad” Rocket

It can go wrong in so many ways…..

Key Principles

• Centre of Gravity - CofG

The point at which the rocket balances.

Key Principles

• Centre of Pressure - CofP

The point at which a silhouette of the rocket balances.

Just like a weathervane

Key Principles

• Stability

A stable rocket is one where the CofG is at least 1 calibre in front of the CofP.

The diameter of the rocket body

= 1 calibre

Summary

• Understand the terms,Centre of Gravity (CofG)

Centre of Pressure (CofP)

Calibre

• Know that stability is achieved when CofG precedes CofP by more than 1 calibre.

• References & Further Reading– Stine (2004), “Handbook of Model Rocketry”– Van Milligan (1995), “Model Rocket Design & Construction”