a check valve failure. The leak detectors wired
in parallel with the loop 2 (2 BL LEAK) sensing
elements.
INTERNAL STORES HEATING SYSTEM
The S-3 aircraft internal stores heating sub-
system is shown in figure 1-14. Crew compartment
exhaust air from the cabin outflow valve is
directed into the sonobuoy compartment ducting.
Part of the exhaust air goes to the cross-fuselage
manifold for channeling into the three sonobuoy
compartments. The balance branches forward
through the bomb bay heating ducting to feed the
two bomb bays. The bomb bay duct separates into
two branches, one to each bomb bay. Air enters
the bomb bays at the aft end, traverses the bomb
bay, and exits through louvres at the forward end
of each bomb bay. In overheat conditions, a
bomb bay overheat thermal switch lights a
warning indicator on the annunciator panel. Air
enters each sonobuoy compartment through the
sonobuoy support channels around the top of the
sonobuoys. Exhaust air from the sonobuoy
compartments is restricted by its passage through
the plenum panels, creating a pressure differential
between the sonobuoy compartments and the out-
side ambient air. This internal pressure inhibits
cold ambient air inflow through the plenum panel
openings.
Figure 1-14.—Internal stores heating subsystem.
1-19
