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Nearly
finished airframe showing composite construction.
The
airplane was made of foam, fiberglass, carbon fiber, Kevlar, and
epoxy. Most parts were formed using a hotwired foam
mold and vacuum bagging. These methods turned out
parts that seemed almost indestructible. 
Wing
being glassed. In
the picture above, you can see the blue wings, which are
made of blue foam covered with fiberglass. The wing
was made in three pieces: two halves and a center
section. Each piece was hotwired separately using wood
rib template as a guide. The panels were then sanded,
"gooed," and sanded again. After installing
the servo wires and plywood mounts, the whole wing was
glassed and bagged. When the epoxy dried, the edges
were sanded smooth. 
Fuselage
center section and H-beam computer tray being glued. The
forward fuselage was the next component built. The two
fiberglass side panels were cut from a sheet of fiberglass
made for the purpose. The sides of the intake ducts
can be seen on the top and bottom of the side panels.
The carbon fiber H-beam was made with foam molds and vacuum
bagging. Eventually the sides of the panels were
covered with foam to give the UAV its round shape.
Note how the wing becomes integrated with the fuselage when
mounted. This arrangement has proven to be very
durable. 
Fuse
center section joined to tubular tail section. The
tubular tail section was joined to the center section with a
molded Kevlar piece. The Kevlar was chosen for its
yellow color and because it had not been used anywhere else
on the airplane. The rest of the tail tube was carbon
fiber. Random note: Kevlar is nearly impossible to
cut, while carbon fiber melts like butter with a cutoff
disk. The Kevlar chewed up about 6 cutoff disks making
the engine hatch.
Tail
fins finished and painted.
The vertical and horizontal tail fins were made from airfoil
shaped balsa covered in a combination of fiberglass and
carbon fiber. Heavy weights were used to press them
flat while curing. All of the tail features were
oversized to enhance stability and controllability.
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