BOMBS USED IN:

FUNCTIONING

ARMED CONDITION

FUZES USED WITH

ARMING TIME

MAX. BODY DIAMETER

OVERALL LENGHT

COLOR

DESCRIPTION:

The fuze consists of a machined fuze body, bored centrally to house (a) an inertia pellet containing the detonator and flash channel; (b) a safety ferrule; (c) a creep spring; and (d) a striker which is riveted into the fuze body. One end of the creep spring rests against a shoulder on the inertia pellet, and the other end is located in a circumferential groove in the bore of the fuze body. The flash channel in the inertia pel-let leads directly from the detonator to the magazine.

A magazine ring is threaded to and cemented on external threads on the base of the fuze body, and crimped to the ring is a magazine containing a gunpowder charge. The magazine is closed by a cupped washer, the hole in which is aligned with the flash channel in the inertia pellet and is covered by a paper disc.

A hole in the fuze body at right angles to the central bore houses a retaining ball and is closed at the outer end with a screwed plug. The inner end of the hole is of re-duced diameter to permit the ball to protrude into, but not fall into, the central bore. A second hole, parallel to the bore, intersects the transverse hole and houses a transit safety pin which retains the ball in a position such that it projects into the bore and prevents the inertia pellet from accidental contact with the striker. The safety pin has a ring passing through its head to facilitate its withdrawal from the fuze.

The fuze has no external for fixing into the bomb, but rather is merely placed in the fuze pocket and held in by the threaded nose plug. Two recesses are bored in the boss of the fuze to engage two projections on the base of the nose plug. This locking arran-gement insures that the safety pin hole in the nose plug is properly positioned over the safety pin and safety pin hole in the boss of the fuze.

OPERATION:

The transit safety pin in the fuze is removed and replaced by a longer safety pin when the fuze is assembled in the bomb. This longer safety pin is removed manually, before the bomb is loaded aboard the airplane, when the bomb is placed in Small Bomb Container. The fuze is then armed. On impact with the target, the inertia pellet over-comes the resistance of the creep spring, bends the tabs on the safety ferrule, and im-pinges against the striker, firing the detonator. The flash from the detonator passes through the flash hole in the inertia pellet and fires the gunpowder magazine, function-ing the bomb.

REMARKS:

(1) Normally these fuzes are shipped in place in the bombs, thus requiring the ship-ping safety pin.

(2) The No. 879 Mk I is identical to the No. 846 Mk I except that it has 5 grams of aluminum powder in the burster well.