GENERAL-PURPOSE BOMBS AND FIN ASSEMBLIES

LEARNING OBJECTIVE: Identify the purpose and use of general-purpose bombs to include shipping configuration, fuze wells and charging circuits, suspension lugs, arming wire assemblies, and fin assemblies.

Low-drag, general-purpose (LDGP) bombs are used in most bombing operations. Their cases (bomb body) are aerodynamically designed, relatively light, and approximately 45 percent of their weight is made of explosives. General-purpose bombs may use both nose and tail mechanical or electric fuzes and conical or Snakeye fins.

The general-purpose bombs currently in use are the LDGP Mk 80 (series). The specifications for the individual bombs are listed in fig 1-20. The basic difference between the bombs listed in fig 1-20 is their size and weight. The following description of the Mk 80 (series) bomb is applicable to all bombs within the Mk 80 (series) unless otherwise noted.

SHIPPING CONFIGURATION

The bomb body (fig. 1-21) is shipped with a plastic plug installed in the nose and tail fuze well to prevent damage to the internal threads and to keep out moisture. The aft end of the bomb body has a metal shipping cap installed. Plastic lug caps are installed in the suspension lug wells, and a plastic plug is installed in the fuze charging receptacle well. Some bombs contain a hoisting lug packaged in the tail fuze well.

Bombs are shipped on metal pallets. The number of bombs loaded on each pallet depends on the bomb size. For example, six Mk 82 bombs can be shipped on a pallet, three Mk 83 bombs can be shipped on a pallet, and two Mk 84 bombs can be _{shipped on a pallet.} Refer to Airborne Weapons Packaging/Handling/Stowage, NAVAIR 11-120A-1.1 or appropriate MIL-STD for more information on shipping configurations.

FUZE WELLS

The bomb body is designed with a nose and tail fuze well. These wells are internally threaded to receive either mechanical or electric fuzes.

FUZE CHARGING CIRCUIT

The forward and aft charging tubes are installed at the factory and contain the electric fuze wire harness. When electric fuzing is used, the wire harness provides a path for the charging current from the fuze charging receptacle to the forward and aft fuze wells.

SUSPENSION LUGS

There are two suspension lug wells for the installation of suspension lugs. The suspension lugs are spaced 14 or 30 inches apart, depending upon the size

Figure 1-20.-Specifications for general-purpose bombs.

Figure 1-21.-LDGP bomb Mk 80 (series-exploded view (shipping configuration).

Figure 1-22-Suspension lug installation.

of the bomb. Suspension lugs (fig. 1-22) are used to attach the weapon to the aircraft bomb racks. An internally threaded well for the installation of a hoisting lug is located between the suspension lugs, at the center-of-gravity (CG) position on the bomb. The hoisting lug is used for handling purposes only.

NOSE PLUGS

There are two basic nose plugs (fig. 1-23) used in general purpose bombs, solid nose plug (MXU-735/B and MXU-735A/B), and the ogive nose plug. The ogive nose plug provides a pointed arch. A support cup is used in the nose well with the ogive nose plug to provide a solid structure to the bomb. The MXU-735 solid nose plug is designed to provide better penetration of hard targets, without the likelihood of nose plug shearing _{during oblique impact.} The MXU-735 replaces the ogive nose plug and support cup.

IDENTIFICATION

The high-explosive filler of the bomb (Tritonal 80-20 or H-6) is identified by the yellow stenciled nomenclature on the bomb body and yellow band(s) around the nose. The lot number is stenciled in white ink on the forward end of the bomb. All Mk 80 (series)

Figure 1-23.-Nose plugs.

Figure 1-24.-Arming wire assemblies.

general-purpose bombs currently being used aboard ships are required to be thermally protected. Thermally protected Mk 80 series bombs can be identified by the words THERMALLY PROTECTED in the identification legend, a bumpy exterior surface, and two yellow bands around the nose.