HULL LAYERS

	The exterior shell of the spacecraft consists of multiple layers which 
afford structural and atmospheric integrity for the spaceframe, integral 
waveguides and field conductive members for the structural integrity field 
(SIF), and pathways for other utilities (including deflector grids), as well as 
resistance to radiation and thermal energy.
	The exterior shell substrate is composed of interlaced microfoam 
duranium filaments. These filaments are gamma-welded into a series of 
contiguous composite segments that are 4.7 cm thick and are typically two 
meters in width. The substrate segments are electron bonded to three 
reinforcing layers of 1.2 cm biaxially stressed tritanium fabric, which provide 
additional torsion strength.
	In areas immediately adjacent to major structural members, four 
layers of 2.3 cm fabric are used. The substrate layer is attached to the major 
structural members by electron-bonded duranium fasteners at 2.5 cm 
intervals. The substrate segments are not intended to be replaceable, except 
by phase-transition bonding using a transporter assembly jig during major 
starbase layovers.
	Thermal insulation and secondary SIF conductivity are provided by 
two 3.76 cm layers of low-density expanded ceramic-polymer composites. 
These layers are separated by an 8.7 cm multiaxis tritanium truss framework, 
which provides additional thermal insulation and a pass-through for fixed 
utility conduits.
	Radiation attenuation is provided by a 4.2 cm layer of monocrystal 
beryllium silicate infused with semiferrous polycarbonate whiskers. This 
layer is networked with a series of 2.3 cm x 0.85 cm molybdenum-jacketed 
conduits. These conduits, which occur at 130 cm intervals, serve as triphase 
waveguides for the secondary structural integrity field. Conductive tritanium 
rods penetrate the waveguides at 10 cm intervals and transfer SIF energy 
into the ceramic-polymer conductive layer.
	The outermost hull layer is composed of a 1.6 cm sheet of AGP 
ablative ceramic fabric chemically bonded onto a substrate of 0.15 cm 
tritanium foil. This material is formed into segments of approximately 3.7 m® 
and is attached to the radiation attenuation layer by a series of duranium 
fasteners, which allows individual segments to be replaced as necessary. 
(Micrometeoroid erosion is kept to a minimum by the deflector shield system, 
but is sufficient to warrant replacement of 30% of leading-edge segments on 
the average of every 7.2 Standard years.) Individual outer hull segments are 
machined to a tolerance of ±0.5 mm to allow for minimum drag through the 
interstellar medium. Joints between segments are manufactured to a 
tolerance of ±0.25 mm.
	Also incorporated into the outermost hull layer is a series of 
superconducting molybdenum-jacketed waveguide conduits which serves to 
distribute and disperse the energy of the tactical deflector system. Selected 
segments of this network also serve as radiators for starship thermal 
management.  Æ