The outer layer of all starships, be they combat or non-combat, must provide defense against artificial and natural threats. For primitive races this armor tends to takes the form of heavy plate metals or layers of thick foam panels attached to the outer hull of the ship. No matter the form, these armored plates add a significant mass penalty to any ship and are not considered viable options for more advanced races. Armor still takes many forms but the most common type of armor found on combat and non-combat starships is found described below:
Outer layers of hull armor are typically composed of multiple layers of nanosheet. Nanosheets are thin panes of carbon nanotubes (typ), which measure 250 times stronger than steel at less than 1/10 the mass. Nanosheet is ideal for use in the outer layers of hull armor for the following reasons:
- As one of the most thermally conductive materials known, nanosheet lends itself to the development of heat sinks, and in the case of space craft, nanosheet armor is often used to supplement or completely replace traditional thermal radiators.
- Because it has a high current-carrying capacity, a film made from nanosheet allows for electrical energy from electrical discharge strikes or energy weapons to flow around the craft and dissipate without causing significant damage.
- Films of nanosheet have also proven effective in the protection of electronic circuits and devices within ships from electromagnetic interference, which can damage equipment and alter settings. Similarly, such films allow military craft to shield their electromagnetic “signatures,” from conventional electromagnetic scanners.
- When layered in the correct fashion nanosheet “weaves” make effective anti-ballistic armor plating.
The layers of nanosheet form a hard outer layer, an effective conductor of heat and energy. Impacts from low energy weapons dump their energy into the lattice matrix, which then spreads it across a much wider area via conduction. Higher energy weapons can breach the lattice if they are strong enough to disrupt the atomic linkages of the carbon nanotubes.
Between the nanosheet panes and the main armor lay a network of fiber sensors and microtubes; the self-repair sheet. The microtubes are composed of open, latticed, nanotube constructs through which an army of carbon construction microbots reside. These tiny microbots, once activated, seep out of the microtubes and repair damage to the outer layers of armor detected by the fiber sensor grid.
The final layers of the protective armor lie beneath the self repair sheet. Here, varying layers of high density composite closed metal/ceramic foam are arranged in ablative sheets. The metal used in the foam can take many forms but most manufacturers use aluminum/titanium composites. This lightweight structural material is preferable for its extreme stiffness and rigidity, as well as its high impact resistance. High velocity ballistics will cause permanent deformation upon impact, however, mandating its replacement.
The armor is cast such that the material density increases as it nears the inner wall. This process shrinks the size and number of foam pocket, making the material more solid. This adds to the material’s resistance to impact and penetration.
Most manufacturers forge the armor in a nitrogen rich environment in order to trap nitrogen in the foam pockets. The addition of the nitrogen in these pockets affords the armor a level of ablative protection. High thermal potential rounds that breach the nanosheet panes vaporize the trapped nitrogen, blowing the melted hull metal outward. The resultant spray of metal particulates has the added benefit of disrupting the cohesion of any additional incident energy weapons further protecting the hull for a short period.
In addition a nanotube lattice weaves throughout the closed metal/ceramic foam. In the event that a ballistic impact has enough force to fracture the hull armor the nanotube can hold the damaged sections together to a limited extent.