PFR - Aerospace Engineering Sciences Senior Design Projects ...

Project Final Report – CUDBF April 30 th , 2009
ASEN 4028: Aerospace Senior Projects
8.2 Missions Mechanical Design Elements
8.2.1 Wing Store Design Element
Although the basic operation of this mechanism was discussed in preliminary design, several
other design considerations had to be made to incorporate the system into a working release
mechanism. The most important of these considerations was the moment that the store CG
would generate on the release mechanism (shown in Figure 1). The CG was placed here to keep
the longitudinal aircraft CG unchanged while the stores are loaded and unloaded. The design
area was limited by physical attachment points located on the underside of the wing.
Figure 47: Store Center of Gravity and Resulting Moment at Mechanism
To allow the wing release mechanism to operate under these conditions, a sliding trigger system
was placed at the forward portion of the allowable design area. At this point, the mechanism
produced a reaction force in the positive Z direction. Towards the rear of the store, the store
mount will actually press up against the underside of the aircraft. Here, a small neodymium
magnet was placed in a pylon that was attached to the store. This magnet wa attracted to an iron
plate in the wing. This will help to decrease load time, keep the store directional aligned with the
aircraft and keep the store secure in negative g-loading flight conditions. To further ensure the
store did not release prematurely, a 1/8” aluminum tab was added to the back of the wooden
store pylon. This tab rests on the inside of the reinforced aircraft skin during negative g-loads.
A diagram of the release system can be seen in Figure 48.
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