Figure 12-56.—Arresting gear mechanism.
Single Shank Centering Devices
Single shank-type arresting hook assemblies are
held in the centerline position for retraction into their
fuselage recesses. The centering devices prevent side
movement of the assembly during carrier-arrested
approaches.
LIQUID SPRING.—The representative arresting
gear mechanism, shown in figure 12-56, uses a liquid
spring for this purpose. The spring is located within a
recess of the hook shank, and the keyed end presses
against the centering cam. On installation, shim the
spring until the thickness of the spacer and shims is
approximately 0.125 inch. Install the spring in the shank,
and then secure the shank to the drag link. Check the
hook point for excessive side play. If side play exceeds
0.24 inch, add more shims to the spring. The total
thickness of shims must not exceed 0.185 inch. Anytime
shim thickness exceeds 0.150 inch, move the hook
laterally several times in each direction to make sure that
the hook can move 40 degrees left and right without
bottoming out the liquid spring.
While liquids are normally thought of as
incompressible, the action of the liquid spring is based
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