Figure 5-9.Transfer switch (portable electrical control
2. Ensure that personnel, aircraft, and flight
deck equipment are clear of the panel area before
attempting to raise the deflector panel(s).
Damage by excessive heat can result
from jet engine exhaust if cooling water is
not flowing at the correct pressure.
3. Check to ensure saltwater supplied from the
ships fire main is flowing through the water-cooled
4. Functionally test the JBD hydraulic and
electrical system for proper operation and leaks.
EMERGENCY OPERATION PROCEDURES
In the event of an emergency or a malfunction,
the procedures discussed in the following paragraphs
must be followed.
Electrical Control Failure
Should the portable electrical control system
box, deckedge, and auxiliary control panels become
affected by an electrical power failure and the
hydraulic system is functional, proceed as follows:
1. Station a crewperson to act as a valve
operator at the four-way control valves in the
catapult retraction-engine machinery room. The
operator shall be equipped with a
sound-powered phone set. The JBD deckedge or
portable control box operator shall remain at his or
her station and relay instructions to the valve
operator. The JBD deckedge or auxiliary panel
operator shall also monitor the pressure gauges.
2. The valve operator, when instructed by the
JBD deck operator, shall raise or lower the JBD
panels by operating the manual overrides on the A
and B solenoids of the three four-way valves. The
B solenoid controls the raising of the panels and the
A solenoid controls the lowering.
The catapult officer, at his or her
may assign two additional
crewpersons as valve operators to expedite
the operation of the applicable JBD
assembly. Instructions are relayed to them
by the first valve operator equipped with a
Hydraulic Control Failure
Should the JBD hydraulic system fail with the
JBDs in the FULL-UP position, the following
procedures must be used to lower the panels.
1. Establish sound-powered phone
communication between the machinery room and
deckedge control/center deck station.
Ensure all tag-out procedures are
according to current shipboard instructions.
2. Close the main supply valve and attach a
3. Open the vent (bleeder) valves to the
lowering chambers of the hydraulic cylinders. Open
the applicable emergency bypass valves one-quarter
turn or as necessary to control the lowering speed of
Be sure that no personnel, including the
holding the panel emergency
lowering device, are under the panel before