aerostatic barge

An aerostatic barge, commonly called aero for short, is a type of airship commonly used in Veldona and Teldona, commonly used for duties such as shipping cargo over difficult terrain, moving particularly valuable cargo, transporting nobles and dignitaries, and military uses.
An aerostatic barge generates lift via air chambers in which metal coal burners heat air, generating lift through displacement of colder air. As such, aerostatic barges best generate lift at low altitudes, where air is thick, and in cool temperatures, where they can most effectively create a thermal gradient. A typical aerostatic barge consists of one to eight or more of these hot air chambers surrounded by a thin wooden frame, under which a gondola is slung which houses the crew, supplies, and cargo. Many also possess a middle deck between the gondola and the air chambers, and a smoke deck above them.
There are multiple classes of aerostatic barges, including, but not limited to:

• Ballisters, heavily-armed fighting vehicles armed with ballistas for air to air combat
• Bombardies, bottom-armored aeros used to drop heavy objects on static fortifications
• Forrears, merchant vessels focusing on cargo capacity rather than fighting strength
• Sylles, swift vessels used as scouts, interceptors, and pirate vessels

History

No aerostatic barges are known to have existed prior to the Fourth Anarchy. Third Empire air travel was not uncommon but thus far none have replicated the mechanical birds used by the Empire.
As far as it is commonly known, the first proper aerostatic barge was a spingalley built by the inventor Belkis Jaya as a cheaper alternative to magical air travel when he designed a lightweight rigid frame around two hot air balloons to carry the anchor for a seagoing vessel over a valley that had become impassible due to flooding in order to get the anchor from the blacksmith to its ship in time for its first launch.

Propulsion

Propulsion is provided by sails, most commonly on the sides but rarely on the top and bottom as well, though ventral sails make it difficult to properly moor an aero and dorsal sails not counterbalanced by ventral sails can cause a level of instability deemed by many operators and designers to be unacceptable. As a replacement or substitute for sails, many aeros use manually-driven propellers (known as "pushmills") for propulsion. Aerostatic barges making use exclusively or primarily of pushmills are known as "spingalleys" while aeros that exclusively or primarily use sails are known as "sailkites" or "sailloons". Regardless of type, many aerostatic barges also feature a vertically-oriented propeller used to ascend or descend below their thermal altitude.

Weapons & Armament

Many forms of weaponry are commonly used aboard aerostatic barges.

• Arrows, fired from archers on open decks or covered ports
• Ballistae, fired from open decks, covered ports, or occasionally free-rotating covered turrets
• Ramming prows
• Heavy weights dropped from altitude

Armor and defense

Most aerostatic barges are lightly armored if at all, and that armor generally consists mostly of wooden boards. The lifting system does not provide enough lift to armor an aerostatic barge with metal except in small, critical locations. As such, aerostatic barges tend to be quite vulnerable to each other's ballistae, and even archers can cause damage to the canvas air compartments of lighter barges.

Used by

• airship Butterfly

Nickname

Aeros