22.214.171.124 Color. Except where NVIS compatibility is
required, the color of advisory signals in the cockpit shall be aviation
green. In other crew stations, advisory signals may be aviation green,
aviation blue, or aviation white. The use of blue or white advisory lights
should be avoided wherever dark adaptation must be maintained. For NVIS
compatibility, the color of advisory lights in all compartments shall be
NVIS green A or NVIS green B, as specified in MIL-L-85762.
126.96.36.199 Legend. Legend type advisory signals installed
in the crew station shall employ translucent legends on an opaque background
as shown on figure 1. The character height of the legend shall subtend a
viewing angle of no less than 20 minutes of arc when measured from the aft
most point of the design eye line (see 3.7). Character proportions shall be
in accordance with MIL-M-8012. The minimum horizontal separation between two
legends shall be two times the width of the widest character. The minimum
vertical separation between two legends shall be two character heights. The
minimum vertical separation between two lines in the same legend shall be
one-half the height of a character.
188.8.131.52 Luminance. The luminance of the signals shall
not be less than 150 fL when the signals are operated at rated voltage at
the point of entry of the light source. In the crew station, advisory
signals shall be dimmed to 1.0 ± 0.50 fL when the pilot's primary interior light
control is "ON". Advisory signals shall be capable of being dimmed to a
luminance of 0.1 fL when NVIS compatibility is required. The design shall
preclude inadvertent dimming during daylight conditions. In other crew
stations, advisory signal luminance may be greater than 1.0 ± 0.50 fL when ambient
conditions so dictate. Except when NVIS are being used within a crew
station, the signals shall be automatically reset to full bright when any of
the following conditions exist:
a. Main aircraft power control is turned off.
b. Primary interior light control is off.
c. High intensity lights are energized.
When an NVIS-compatible lighting mode is being used within a
crew station, the lighting circuit logic shall preclude the system from
obtaining a luminance level which will degrade external vision or NVIS
184.108.40.206 Presentation. Advisory signal presentation
shall be steady "ON", unless otherwise specified by the acquiring activity