325-, 350-pound Depth AN-Mk 53 Mod 1 (TNT), AN-Mk 54 Mod 1 (HBX), Mk 53 (TNT), and Mk 54 (Torpex)

Over-all length, inches

Body length, inches

Body diameter, inches

Wall thickness, inch

Tail length, inches

Tail width, inches

Filling

Weight of filling

Total weight

Charge/weight ratio

Fuzing

Nose - AN-M103, AN-M103A1 (must have modified arming vanes for use with flat-nose bomb). AN-Mk 219 (with an adapter ring) may be used in the nose if the AN-M103 with the modified vanes is not available. The AN-Mk 219 requires 2,500 feet of air travel to arm.

Tail - AN-Mk 230 Mods 4, 5, and 6 or Mk 231 (hydrostatic).

Body construction: The cylindrical welded sheet-steel body has a flat nose. A base closing plate is secured to the rear of the bomb by four bolts. A base closing plate is se-crued to the rear of the bomb by four bolts.

Suspension: These bombs are suspended horizontally by two lugs seven inches on each side of the center of gravity, or by a single lug at the center of gravity and 180° removed from the other lugs. There is no external band, the bombs being strengthened internally by a band which is fitted into the bomb at the center of gravity. Trunnions for dive bombing may be threaded to the case and internal strengthening band.

Tail construction: Welded to the tail cone are four vanes which are strengthened by interior box-type struts, and an exterior wide ring strut. The tail cone is secured to the base closing plate by four bolts.

Markings: Olive drab over all. "Mk 53-325 lb. depth bomb", "Mk 54-350 lb. depth bomb" stencilled on the respective bomb bodies in yellow if the filling TNT, or in blue if the filling is Torpex.

Remarks: These two bombs (identical except for filling) have been designed to re-place depth bombs using athwartship fuzes, since difficulties have been encountered at times in the past with the Athwartship Fuzes AN-Mk 224 and AN-Mk 234. The Depth Bombs Mk 53 and Mk 54 will use the Tail Hydrostatic Fuze AN-Mk 230 and a nose fuze, having no athwartship pocket.

The Depth Bombs AN-Mk 53 Mod 1 and AN-Mk 54 Mod 1 differ from the Depth Bombs Mk 53 and Mk 54 respectively in that the suspension lugs are welded on, instead of being of the screw type. In addition, the walls of the explosive cavity of the two bombs are coated with an asphaltic composition known as Hot Melt. The AN-Mk 54 Mod 1 is loaded with HBX rather than Torpex.

Only the modifications of the Depth Bombs Mk 53 and Mk 54 have been standardized as AN bombs.

Figure 291. 325-pound Depth Bombs AN-Mk 53 and AN-Mk 54