An 18-foot diameter cruciform-shaped canopy
parachute suspension system is used for good stability.
The riser cables connect the parachute to a bulkhead.
The bulkhead separates the parachute compartment
from the remainder of the flare assembly. One cable is
attached to an explosive bolt for parachute dump at
candle burnout.
In the ignition system, a lanyard is attached to one
of the parachute riser cables. This lanyard is threaded
through the bulkhead and past the candle in an internal
raceway along the side of the aluminum case. This
leads to the ignition assembly in the ignition housing
near the candle's face. The lanyard is attached to a
triggering mechanism, which consists of the out-of-line
igniter (OLI-2/A). Upon ignition, the firing pin initiates
the pyrotechnic firing train.
The aluminum case assembly contains a tamp-cast
illuminating candle that consists of a composition of
magnesium, sodium nitrate, and a polymer binder. The
flare is designed so the outer aluminum case is partially
consumed during candle burning.
Operation
A lanyard is attached to the timer knob on the flare
timer during flare uploading procedures. The lanyard is
also connected to the flare drogue tray or bomb rack,
depending on the launch configuration. At launch, the
timer knob is pulled out of the timer (requires
approximately 30 pounds of force) by the lanyard,
starting the clock mechanism. After the preset time
(drop distance) ends, the three locking pawls in the
timer assembly release, retracting and releasing the
timer assembly. A spring, located between the timer
assembly and the packaged parachute, expels the timer
assembly, which, in turn, initiates removal of the
parachute from the flare case. When the cord breaks, it
separates the timer assembly from the parachute. As the
parachute system deploys and its main cables are pulled
taut, the ignition lanyard is pulled to activate the
ignition system. The ignition lanyard must exert a pull
force in excess of 90 pounds to pull the slider assembly
in line. This, in turn, releases the firing pin against the
primer. The primer ignites a propellant wafer that
produces sufficient heat for candle ignition. Pressure
buildup during candle ignition blows off the igniter
housing, and the candlepower reaches a nominal value.
Just before candle burnout, the explosive bolt functions
to release one of the suspension cables, causing the
parachute to dump.
The LUU-2B/B candle is not ejected from the case
on the LUU-2B/B. Only the parachute is removed from
the case. A mechanical timer and spring accomplish
this. Therefore, if the timer knob should be accidentally
pulled during handling when the timer is not on the
SAFE setting, the timer and release mechanisms can be
forcibly hand-held onto the flare housing to prevent
ejection of the timer and release mechanisms. When the
timer completes its cycle, the timer mechanism can be
taped on the flare housing and marked for disposal. If
the timer is ejected from the flare and a portion of the
parachute comes out of the housing, the parachute can
be stuffed back into the housing, taped, and marked for
disposal.
The LUU-2 B/B flare has increased pull force on
the parachute lanyard to initiate the ignition sequence.
If the parachute should accidentally deploy on the flight
deck/line, the opening shock from deck winds or jet
blast is not sufficient to ignite the candle.
REVIEW NUMBER 2
Q1.
What is the approximate weight of the
LUU-2B/B aircraft parachute flare?
Q2.
The components of the LUU-2B/B flare are
_________________.
Q3.
What is the minimum drop distance setting of
the LUU-2B/B flare?
Q4.
What is the diameter of the parachute
suspension system?
Q5.
At launch, the timer knob is pulled off of the
timer by what amount of force on the lanyard?
AIRCRAFT-LAUNCHED SMOKE AND
FLAME MARKING DEVICES
LEARNING
OBJECTIVE:
Describe
the
physical
and
functional
aircraft-launched
smoke and flame marking devices. Recognize
the methods used to launch them.
Smoke and flame marking devices are pyrotechnic
devices dropped on the ground or on the water's surface
to
emit
smoke
and/or
flame.
Reference
points
established by these devices serve a variety of purposes.
They can be used to determine wind direction and
approximate velocity, mark the location on the surface
for emergency night landings, establish an initial
contact point for continued search for a submarine, or
locate target areas in antisubmarine warfare.
4-7
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