Biological Hulls

by Darrin Drader

August 6th, 2003

The hulls in the book Airships represent the most common and easy to manufacture hull types. In addition to these are ships sailing the skies with hulls made from more exotic materials that have either once been alive, or are alive now. These are the biological hulls, which are often employed by the more intelligent or magically advanced races of the world.

The advantage of biological hulls is that they are usually lighter, able to heal their own damage over time, and sometimes they have the ability to increase in size as they grow older. The disadvantages are that nourishment must somehow be provided for, they are slightly weaker than hulls constructed from standard wood or other inorganic materials, and they eventually die of old age.

Unlike standard hulls, biological hulls are grown rather than created from inorganic materials. These living materials, are either put into place in chunks and then grafted together into a cohesive whole, or they are grown slowly, stretched, and molded to take the desired form. They still require the standard airship production facility, frames, and laborers to build. The laborers must all be experts in order to construct biological hulls.

Sustaining damage is an inevitable occurrence during the ship’s lifetime of service. Healing occurs at the rate listed in each entry, though hulls must still be alive in order to heal themselves. Clerics and other classes capable of healing may heal biological hulls. When they do so, hardness is not taken into account, and they cure a number of hull points equal to the number of hit points their spells normally heal.

Biological hulls require nourishment. In some cases this nourishment takes the form of food, while in other cases it may be sunlight or even water. If the hull does not receive the necessary amount of nourishment each day, it begins to starve. The starvation rules in the DMG apply, though the subdual damage applies to each ton of the ship. A ship with a hull that has dropped to 0 points because of subdual damage is no longer airworthy and must receive nourishment within 1d6 days or die.

The types of biological hulls available are chitin, plant, coral, and shell.

Chitin

Chitin is the hard material that forms the exoskeleton of most insects. The process involved in making a chitinous hull begins with polymorphing a regular size beetle into a new creature known as a radipon. A radipon initially appears as little more than a large bowl shaped object made of chitin. The radipon is then grown on a ship frame, all the while being treated with oils that make the shell malleable and prevent the polymorph effect from being dispelled. The chitinous hull is in fact a living insect, fully encased in its shell. The only portion of the insect that retains movement is its mouth, which is located at the bottom of what becomes the hold. It must be fed 5 lbs. of meat each day. The waste material from this creature is released from a small opening in the tail end of the vehicle once per week. This is a popular hull type among insectoid creatures, as well as the xill.

Benefit: This is a strong biological hull material that is able to heal damage at a rate of 2 HP per ton per day. Creatures that use this hull point also gain a +5 bonus to Intimidate checks while aboard against creatures that do not serve aboard the vessel.

Penalty: As a living, non-plant like organism, it is possible for a chitin hull to die as the result of massive damage. Massive damage to a hull is defined as a single strike that deals 150 hull points in a single attack.

Plant

Plant hulls are made of a single type of plant called steelreed. This leafy plant is found in nature, though usually doesn’t grow larger than 5 ft. tall. When used for a hull, the plant is placed on the ship frame, treated with nutrients, and stretched. Part of this process includes a natural hardening of the exterior shell. The plant hull requires only sunlight and water for nourishment. The ordinary light from the sun is enough to provide for most of its required nourishment. Once per week it must land and float in a body of water larger than it’s own size for eight hours so that it can be properly nourished. This hull is popular among elves and other creatures that like to be near nature at all times.

Benefit: The plant hull is light, reducing the tonnage of the vehicle. It can be crafted into vehicles of any size, and if desired by the owner, it can grow into a larger sized hull after 1d4 years. It heals at a rate of 1 point per ton per day.

Penalty: Aside from glass, the plant hull is the weakest hull available.

Coral

Coral hulls are created underwater by cutting pieces of coral, carving them into the desired shape, placing the pieces near each other, and then grafting them together with new coral-forming organisms. Unlike the majority of the other biological hulls, coral hulls are no longer alive, and neither heal themselves nor require nourishment. Despite this, they must be set down in salt water once per week for at least 8 hours in order to preserve its structural integrity. Repairing coral hulls requires the ship to be set down in a body of water for three days per cumulative ton of damage (15 points), and the expenditure of one quarter the base price of the hull (10,000 gp. per ton).

Benefit: It has the properties of a rock hull while being lighter and easier to repair.

Penalty: The unusual facilities needed to construct them makes this hull expensive.

Shell

Created from two massive interlocking creatures similar in nature to crabs, these hulls are strong and durable. The creatures used for these hulls remain alive, although they lose their freedom of movement. Their large black eyes are front faced. It is believed that these are intelligent creatures that choose this life so that they can explore the world in a way that would be impossible while living beneath the sea. Shell hulls require landing in a body of water larger than it for 8 hours once ever 2 days. During this time they replenish their supply of water and gain nourishment by eating bacteria and small microbial creatures.

Benefit: This is a strong hull type that is able to heal 3 HP per ton per day.

Penalty: It must return to the sea for nourishment more often than other hulls.

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