Although not classified as practice bombs, the Mk 80 (series), inert filled, LDGP bombs are used for full-scale practice bombing. These bombs are physically the same as the Mk 80 (series) LDGP service bombs, but they do not contain explosive filler and are painted blue. These bombs provide full-scale training for assembly and loading crews and pilots. The general types of practice bombs are subcaliber or full-scale practice bombs. Subcaliber means that the practice bomb is much smaller in size and weight than the   service   bomb   it   simulates.   Full-scale   practice bombs are representative of service bombs in their size and weight. 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. Mk 76 Mod 5 The Mk 76 Mod 5 is a 25-pound, solid, metal-cast, practice  bomb  (fig.  1-34).  Its  body  is  teardrop  shaped and centrally bored to permit the insertion of a practice bomb signal cartridge. The after body, which covers the tail   tube,   is   crimped   to   the   bomb   body   and   has welded-on 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. BDU-48/B The BDU-48/B is a 10-pound practice bomb (fig. 1-35).   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. 1-35) 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. REVIEW NUMBER 8 ANSWERS A1. The cargo section is the main structure of the Mk 7 bomb dispenser. A2. The Mk 20 bomb cluster weighs 490 pounds and holds 247 Mk 118 antitank bomblets. A3. The tail cone assembly, attached to the aft end of the cargo section, stabilizes the bomb after it is released from the aircraft. A4. The  Mk  339  Mod  1  mechanical  time  fuze  is used  to  initiate  the  linear-shaped  charges  in the cargo section wall. A5. The Mk 118 Mod 0 and Mod 1 antitank bombs contain the following:   Mk 1 Mod 0 fuzing system   Shaped-charge warhead   Fixed stabilizing fins A6. The  Mk  427  Mod  0  and  Mod  1  shipping containers are used to ship and store Mk 20 bomb clusters. 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. 1-36) 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 1-38 Figure 1-34.—Mk 76 Mod 5 practice bomb.