of the flare case opposite the flanged base is closed with
an aluminum closure disk.
When properly installed in the chamber of a
dispenser, the cartridge retainer fits snugly over and
around the firing end of a corresponding Mk 131
impulse cartridge. When the cartridge is fired, gas
pressure causes the hammer to move into the adapter,
locking the adapter and the piston together. Gases from
the fired cartridge expand to exert a pushing force
against the piston. This removes the closure disk and
ejects the flare grain. As the piston strikes the piston
stop, the adapter to which the pull wire is firmly attached
separates from the igniter cup. Then, the adapter travels
with the flare grain. This action causes the igniter to
move over the friction material on the crinkled end of
the pull wire, igniting the ignition composition. Flame
flashes through the longitudinal hole in the flare grain
and ignites the first-fire composition in both the
longitudinal hole and the cross hole. The first-fire
composition ignites the flare grain on all surfaces.
The flare is rendered safe during normal handling
operations by the segmented adapter. If the closure disk
is accidentally displaced, the entire grain and the igniter
assembly slips out of the flare case without igniting.
The device arms only after an impulse cartridge is fired
and bends the sharpened edges of the adapter so it is
locked to the piston.
PRACTICE BOMB SIGNAL
CARTRIDGES
LEARNING OBJECTIVE: Identify the
purpose and use of practice bomb signal
cartridges.
Practice bomb signal cartridges are used for day and
night operations and as a visual indication of bomb
A1.
A2.
A3.
A4.
A5.
A6.
A7.
A8.
A9.
A10.
REVIEW NUMBER 3 ANSWERS TO QUESTIONS Q1. THROUGH Q10.
The burn time of the Mk 25 Mods 2 and 3 marine location markers is between 10
and 20 minutes.
The Mk 25 Mods 2 and 3 marine location markers function in the same way, Mod 2
contains two saltwater-activated batteries and two related squibs. Mod 3 contains
one battery and one squib.
The heavy aluminum base assembly crimped to the outer tube sits in the water
and causes the candle to sit out of the water.
The Mk 25 and Mods marine location marker is launched by hand or by sonobuoy
launcher.
The Mk 34 adapter kit is used when the Mk 25 and Mods marine location marker
is launched from sonobuoy launchers.
The Mk 58 Mod 1 marine location marker is used for antisubmarine warfare,
search-and-rescue operations, man-overboard markings, and as a target for
practice bombing at sea.
The Mk 58 Mod 1 marker produces a yellow flame and white smoke for 40 to 60
minutes.
Under normal conditions, the flame and/or smoke of the Mk 58 Mod 1 marker is
visible for 3 miles.
The Mk 58 Mod 1 marine marker is hand launched, externally launched from
aircraft bomb racks, or launched from sonobuoy launchers.
The Mk 72 Mod 1 seawater-activated battery is used with the Mk 58 Mod 1 marker.
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