Type of filling: Type 98 explosive (HND/TNT N 40/60) with picric acid booster and tetryl detonator.

Description: This is a hemispherical, chemical-horned, all-welded mine. The outer body forms a hemispere and has two handles on its upper portion, a central opening on top to take the booster and safety switch, and two horn openings 180° apart. The mine is de-vided internally into an explosive chamber and a chamber containing booster, wiring, safety switch, and horn electrodes. The division is made by a shallow, saucer-shaped steel section, which forms less than a hemisphere which is pressed into the outer body from the bottom and welded in place. A plate is then fitted into the bottom of the mine and is also welded in place. This last-mentioned plate carries a filling plug in its center and is inset 13/16 of an inch to allow clearance for the plug. The horns, two in number, appear to be standard lead-acid mine horns. They are set at an angle of about 65° and project above the level of the mine top; threads are left hand. In the firing circuit is a spring-loaded plunger whose upper end projects through the safety-switch cover. A rub-ber diaphragm in the top of the cover insures watertightness but allows the plunger to move. There is a tapered, threaded hole in the center of the top of the plunger and a groove around the plunger near the top. Until the mine is in position a safety fork enga-ges this groove and holds the plunger up against its spring. The inner end of the plunger is thus withdrawn from between two contacts in the electrical firing circuit and the cir-cuit is incomplete.

Employment: Used on beaches as an antiboat mine. It can also be used on land as an antitank mine by burying or otherwise concealing it.

Operation: After the mine is laid the safety fork is removed. The contact plunger moves down under spring pressure and closes the electricial contact, thus completing the elec-trical circuit and the mine is armed. When a horn is crushed an acid vial inside is broken, allowing the acid to drain down onto two plates of a small battery which generates suffi-cient amperage to fire the detonator. As the wiring is series-parallel, either horn on being bent will act independently to fire the mine.

Remarks: The Japanese designation is: Small type land mine.

Figure 167 – Type JE Antiboat Mine.