• Early theories of air travel
• Lighter-than-air craft
• Words to Know
• Heavier-than-air craft
• Four fundamental aerodynamic forces
• Aircraft stability
• Jet engines

An aircraft is a machine used for traveling through the atmosphere. There are two types of aircraft: the first type are known as lighter-than-air crafts, which are supported by their own buoyancy or ability to float. The second are known as heavier-than-air crafts, which require the use of some sort of engine to propel them through the air.

Early theories of air travel

Humans have dreamed of flying like birds for...