The firing mechanism is secured in the safe
position by a safety pin that passes through the
handle. The safety pin prevents the handle from
being squeezed and pulled.
When the initiator handle is squeezed and
pulled for a distance of 0.75 inch, the firing pin
separates from the sear pin. From this point, the
sequence is identical to the external canopy and
hatch jettison sequence.
SHIELDED MILD AND FLEXIBLE
CONFINED DETONATING CORDS
The SMDC and FCDC segments act as the
plumbing for the emergency egress system. They
provide all internal and external jettison initiators
with manifolds and one-way transfers to all
explosive charges. Some S-3A aircraft have been
modified to incorporate FCDC in place of the
SMDC at the four locations where the canopies
and/or hatches meet the airframe. The use of the
FCDC alleviates the installation problems
encountered with SMDC. The SMDC and FCDC
focus extremely high velocity and pressures onto
the ends of adjacent SMDC segments.
The high reaction speed of 8,000 to 9,000 feet
per second makes the SMDC very difficult to
unintentionally detonate from extraneous sources
such as sawing, filing, drilling, and hammering
because the speed of these operations does not
approach the 8,000 to 9,000 feet per second
requirement. From the standpoint of manufac-
turing and maintenance personnel, the system is
virtually inert when safety pins are installed.
Figure 2-16.—Hatch/canopy detonating cord assembly.
2-20
