PFR - Aerospace Engineering Sciences Senior Design Projects ...

Project Final Report – CUDBF April 30 th , 2009
ASEN 4028: Aerospace Senior Projects
The metal motor mounts were fabricated by printing out a template from SolidWorks © and then
gluing the paper to thin aluminum sheeting. The shape was cut out using a bandsaw and the
rough edges filed to prevent injury. Holes were then drilled into the metal in the appropriate
places marked on the template. Once this was completed, the mounts were bent on a sheet metal
bender.
Given their unique shape, the main landing gear could not be purchased and thus had to be built
from scratch. To begin construction, plywood mounts for the main gear were cut, the corners
rounded, and blind nuts secured into the mounts to attach the main gear spars to the mounts.
Al2024 spars were store-bought and the necessary bend locations marked along the spars. Each
gear spar was bent by hand using a strong table mounted clamp and a hammer, making sure to
bend the sections attached to the mount at a 90 degree angle, the longest sections at a 10 degree
angle, and the section which holds the wheel at a 90 degree angle. Once the spar was bent, 1/8
inch aluminum sheeting was cut into 1.5 inch long strips ¼ inches wide in order to secure the
main gear strut to the plywood mount. The strips were then hammered over a piece of the
aluminum spar to bend them into a horseshoe-like shape. Holes were then drilled into the strips,
which were bolted into the blind nuts on the plywood mounts, securing the spars to the mounts.
The main gear was then completed by attaching wheels and collars at the base of the spar.
12.3 Wingtip Sub-Assembly
Figure 108: Wingtip Interior Sub-Assembly
While the interior and exterior sub-assemblies were being completed, other team members were
beginning work on the aircraft wing. To begin fabricating the verticals, the main wing was first
separated from the wingtip at the fold location using a hot wire cutter. After the cut was made,
the aileron was removed. The aileron was then sheeted, sanded, and monokoted. Small holes
were then drilled along the aileron leading edge and small hinges similar to those used in the
rudder where glued into the aileron. The wingtip was then subjected to a series of hollows using
a routing bit and a drill press. Holes were made for the wiring, balsa spar, and release
mechanisms (to include the release mechanism mentioned above as well as the small metal plates
that attract the magnets located in the wingtip stores and the servo). Once the holes were
created, the release mechanisms were glued into place and balsa covers glued on top of the
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