SUBCALIBER PRACTICE BOMBS

There are two types of subcaliber practice bombs-the Mk 76 Mod 5 and BDU-48/B. The two types are used for practice and are quite different in design and appearance from each other. Each type is discussed in the following paragraphs.

Mk 76 Mod 5

The Mk 76 Mod 5 is a 25-pound, solid, metal-cast, practice bomb (fig. 1-41). Its body is teardrop shaped and centrally bored to permit the insertion of a practice bomb signal cartridge. The afterbody, which covers the tail tube, is crimped to the bomb body and has welded-on conical tail fins. The bomb is designed with single lug suspension, using the Mk 14 suspension lug.

The Mk 76 Mod 5 practice bomb is designed for impact firing only. It uses the Mk 1 firing pin assembly to initiate the practice bomb signal cartridge. The bomb signal and the firing pin assembly are held in the bomb by means of a cotter pin.

The bomb is painted blue. The identification nomenclature is stenciled in white letters on the bomb body.

Figure 1-41.-Mk 76 Mod 5 practice bomb.

Figure 1-42.-BDU-48/B practice bomb.

BDU-48/B

The BDU-48/B is a 10-pound practice bomb (fig. 1-42). It is a thin-cased cylindrical bomb used to simulate retarded weapon delivery. The bomb is composed of the bomb body, a retractable suspension lug, a firing assembly, and box-type conical fins.

The firing device (fig. 1-42) consists of a firing pin assembly and a cotter pin. The BDU-48/B is painted blue. Identification nomenclature is stenciled in white letters on the bomb body.

The bomb can use signal cartridge Mk 4 Mod 3, or CXU-3A/B. While handling or transporting bombs, loaders should avoid placing their bodies in line with either end of the bomb.

FULL-SCALE PRACTICE BOMBS

Full-scale practice bombs have the same dimensions, weight factor, and configuration abilities as the service bombs they simulate. The bombs are filled with inert material to obtain the proper weight.

The full-scale practice bombs (fig. 1-43) currently in use are in the Mk 80 (series). They include the

Mk 82, Mk 83, and Mk 84 LDGP bombs. These bombs are assigned a different NALC than their service counterpart to differentiate between inert and service bombs when requisitioning them through the supply system. They can be configured with the same bomb components (fuzes, fins, lugs, and so forth) that are used to configure service bombs. However, if the use of fuzes is not desired, a Mk 89 Mod 0 bomb spotting charge adapter can be installed in the tail fuze well of the practice bomb to provide visual observation of weapon/target impact.

The Mk 80 (series) inert LDGP bombs are painted blue. The new Mk 80 (series) inert LDGP bombs have an olive-drab colored exterior and are thermally protected, but they can be distinguished from service

Figure 1-43.-BDU-45/B practice bomb.

bombs by a blue band around the nose and by the 1-inch letters INERT stenciled on the outside of the bomb body.

The Mk 89 Mod 0 bomb spotting charge adapter (fig. 1-44) is designed for use in the tail fuze well of the Mk 80 (series) LDGP inert bombs. A practice bomb signal cartridge is installed in the Mk 89 Mod 0, which provides visual observation (smoke) of weapon-target impact.

The bomb spotting charge adapter is kept in a safe condition during ground handling by the installation of a safety cotter pin in the safety pin sleeve. Once the arming wire has been installed through the arming wire hole in the safety pin sleeve, the safety cotter pin must be removed.