In some aircraft, tiny grain-of-wheat lamps
figure as you read this section. The lighting
have permanent mounts in the control-box panels.
equipment consists of edge-lighted control panels,
Having been aged and carefully selected for
individual lights for instruments, and red flood-
lights for overall lighting. The edge-lighted panels
the lifetime of the aircraft.
provide diffused lighting for the control and
Cavities and shallow trenches in the panel back
indicator panels.
accommodate the panel connector, lamps, and
Some instruments have a light source as an
route lamp leads to the panel connector. The
integral part of the instrument, and all instrument
connector, lamps, and leads are then potted into
designs will soon have integral lighting. Since
the back of the panel with a clear plastic potting
individual lights for instruments are compatible
material. Normally, the lamps are in parallel, and
with the integrally lighted instruments, the two
failure of one lamp will not appreciably degrade
types of light sources may be intermixed.
the panel lighting. The main advantages of
Edge-lighted control and indicator panels (fig.
embedded lamps are long life, ruggedness,
4-9) have a nongloss, black background with white
lamp assemblies are mounted so light is diffused
through the plastic panels. These lamps have red
Cockpit Lights
filters to cut out glare. Bulb replacement is
relatively simple, Just unscrew the top cap from
The term cockpit lighting is rather broad. Its
the assembly, pull the bulb from the cap, replace
meaning varies, depending on the type aircraft
the bulb, and reassemble the unit.
being described. In fighter-type aircraft, it may
Most instrument lights consist of panel lights
be interior lighting that consists of individually
and instrument integral lights. The essential bus
lighted instruments and switches, lighted control
powers the instrument lights through circuit
panels, and necessary floodlights. It includes the
interior lighting just mentioned as well as many
The CONSOLE panel lights control is a
other special lighting assemblies.
variable intensity control for the console panel
A much used lighting device is the small
edge lights. As the control rotates clockwise, the
incandescent spotlight known as a utility light
intensity of the console edge lights increases. Also,
assembly. These assemblies, installed at crew
as the control rotates to the OFF position, a switch
stations, are in a position where they provide
within the control actuates, removing power from
the console flood switch dim contact. Therefore,
uses. The light from the lamp assembly can focus
the console red floodlights operate in dim only
in either a small spot or in a wide beam. It also
when the console panel lights control is in a
position other than OFF.
one type of light in which an ON-OFF switch and
The CONSOLE FLOODS switch is a three-
an intensity control rheostat control light
position switch (BRT/DIM/MED) for selecting
operation.
the intensity of console floodlights. Selection of
Cockpit extension light assemblies provide
the BRT or MED position energizes the lights
crew members with an extension light for reading
regardless of the position of the console panel
maps or illuminating small areas. These assemblies
lights control. The WHITE FLOOD switch has
consist of a connecting cord, switch, and lamp
two positions--OFF and ON. Placing the switch
housing assembly. By adjusting the assembly, you
to ON energizes the white floodlights. The
can change the size of the light beam.
NORMAL WARNING LIGHTS switch has two
positions--NORMAL and TEST--and it is spring
Indicator Lights
loaded to the NORMAL position. Placing the
switch in the momentary contact TEST position
Cockpit personnel get aircraft operating status
illuminates all of the warning lights in the pilot's
from various indicator (warning, caution, and
cockpit.
advisory) lights in the cockpit. These lights have
many purposes, such as showing the position of
The INSTR PANEL EMERG FLOOD switch
the landing gear, arresting hook, wings, and bomb
(fig. 4-9) has three positionsOFF, DIM, and
bay doors. They can also show low oil pressure,
BRT. The switch turns on the red floodlights
equipment overtemperature, generator failure,
above the main instrument panel in an emergency
and other data.
when normal instrument lighting malfunctions.