Glossary

Airship Lighter-than-air craft. These ships are able to fly because they contain a substance that is lighter than the air around them. Generally includes hot-air balloons and blimps.

Aerostat Generic term for the two forms of lighter-than-air crafts, the hot-air balloon and the airship (blimp).

Anatomy of a Blimp (http://rbmn03.waika9.com/blimps6.htm)

Tail Aligned in an X formation. Guides the vertical and horizontal movement. The tail is a combination of rudders and elevators and is therefore called a "ruddervator."

Envelope Holds the helium. Made of two-ply polyester fabric.

Ballonets Air bags inside the envelope -- helps to maintain a constant pressure.

Catenary curtain Cemented to the inside of the envelope -- it supports the blimp with cables.

Nose Cone Battens Supports the blimp's nose. Also helps when anchoring to the ground.

Secondary Mooring Used to secure the blimp to the top of the ground crew's bus.

Air valves Allows air to escape from the ballonets to maintain envelope pressure.

Gondola Holds the passengers and the pilots.

Dirigible French synonym for "airship." The term generally means "to control" or "steer."

Helium The second lightest inert gas. It is colorless, tasteless and odorless. Has a somewhat inferior lifting power than hydrogen, but will not burn or explode.

Hydrogen The most abundant element in the universe, making up more than 90% of its atoms. Hydrogen is the lightest element and therefore has the most lifting power. It is also highly flammable.

Types of Airships (http://www.howstuffworks.com/blimp4.htm)

All airships have solid gondolas, engine-powered propellers and solid tailfins.

Rigid Usually long (greater than 360 ft/120 m) and cigar-shaped with an internal metal frame and gas-filled bags (such as the Hindenburg).

Semi-rigid Pressurized gas balloon (envelope) attached to a lower metal keel.

Non-rigid (blimp) Large gas-filled envelopes (such as the Goodyear blimps).

Zeppelin A proprietary or trade name applied to those airships made by the Luftshiffbau Zeppelin G.m.b.H. The term is often used as a generic term to mean a blimp.