Lesson 4/Learning Event 2
The blackout stoplight, marker light, and taillight are designed to be visible at a horizontal distance
of 800 feet and not visible beyond 1,200 feet. The lights also must be invisible from the air above
400-feet with the vehicle on upgrades and downgrades of 20 percent. The horizontal beam cutoff
for the lights is 60 right and left of the beam centerline at 100 feet.
The composite light is currently the standard lighting unit that is used on the rear of tactical
military vehicles. The composite light combines service stop, tail, and turn signals with blackout
stop and taillighting.
Controls and Lockouts
Blackout lighting control switches are designed to prevent the service lighting from being turned on
accidentally.
Infrared Lighting
Infrared lighting provides vision to troops at night, like blackout lighting. Unlike blackout lighting,
however, infrared lighting is undetectable to the human eye. There are two basic types of infrared
lighting systems: the active system and the passive system.
- The active system uses a light source combined with a red lens to emit light in the near
infrared range. The emitted light is reflected back from the illuminated object and
focused in an image-converter tube. The tube converts an image formed in one
wavelength of radiation into an image in a visible wavelength for viewing. The tube
contains both the sensor and display in one unit. The infrared lighting system
employed on present tank-automotive vehicles is of this type. The active system has
the disadvantage of being detectable by an enemy equipped with infrared detectors
operating in the same range. For this reason, the active system equipment is expected
to be phased out completely and replaced by passive systems.
- The passive system cannot be detected or disabled by methods that are effective against
active systems. Furthermore, most natural objects radiate in the infrared region,
making a passive system very attractive. There are basically two types of passive
systems: light intensification and far-infrared.
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