The 28-inch pitch diameter sheave
containing the ball thrust bearing is not
lubricated with the automatic lubricating
system. The ball thrust bearing eliminates
the need for constant lubrication.
Lubricating the ball thrust bearing sheave is
accomplished with a manually operated
grease gun after every 20 to 30 arrestments.
(See fig. 3-16 for an illustration of the
automatic lubrication system.)
CABLE ANCHOR DAMPER
The cable anchor damper installation consists of
two identical cable anchor damper assemblies, which
are either deck mounted or overhead mounted (fig.
3-17). Compartment configuration determines how
the units are installed.
The purpose of the cable anchor damper is to
eliminate excessive purchase cable slack between the
crosshead and fixed sheave assembly at the
beginning of the arrestment stroke. Through service
use and experimental testing, it was found that when
this cable slack was taken up by the landing aircraft,
excessive vibrations occurred in the engines. The
cable anchor damper removes this slack as it occurs,
thereby eliminating vibration of the purchase cable.
The cable anchor damper assembly is used with
pendant engines only.
Referring to figure 3-17, note that each cable
anchor damper assembly includes a cylinder that
connects to an operating end head and a cushioning
end head. Piping connects the engine cylinder to
the operating end head through a manifold tee.
Two lines branch from the manifold tee, one to
each damper assembly operating head. Each of
these lines contains a flow control valve. A cover
is placed over the operating piston rod and coupling
Figure 3-15.Fixed sheave assembly.