BOMBS USED IN

FUNCTIONING

ARMED CONDITION

ARMING TIME

MAX. BODY DIAMETER

OVERALL LENGTH

DESCRIPTION:

This fuze consists of a body containing an igniter mechanism, a delay system, a set-ting ring and magazine charge igniters, and a magazine holding a gunpowder charge. The igniter mechanism comprises a spring-loaded striker and a detonator located in a horizontal channel in the fuze body. The striker is held in a firing plug by two retaining balls which engage an annular groove in the striker. The firing plug protrudes from the fuze body and is attached to the aircraft by a fuzing link. A safety pin, screwed into the body, retains the striker in the safe position.

The delay system consists of a quantity of delay composition contained in two groo-ves out into the upper and lower surfaces of the fixed delay ring. A bridge of metal se-parates the ends of each of groove, and a long pellet connects the grooves. The pow-der in the lower groove provides a fixed minimum delay period and communicates with a firing channel located between the detonator and the exhaust plug. The fixed delay ring is secured to the fuze body by a locating pin, and its outer surface is graduated in hun-dreds of feet up to 800, and thereafter in thousands of feet, representing the distance of fall before the magazine is fired.

The setting ring, on which a red setting arrow is marked, contains two short igniter pellets, and a hole leads from the upper pellet to an annular groove formed in the ring. This groove is aligned with an annular groove out in a spigot which is screwed into the fuze body. A number of long igniter pellets, arranged in the form of a cross in the spi-got, communicate with the groove in the spigot. A flash channel leads down from the center of the cross, through the spigot, and into another flash channel in the fuze body, the latter channel leading to the magazone. A tensioning ring, locked in position with grub screws, determines the ease with which the setting ring may be rotated.

The magazone consists of an apertured magazine over held in position by a base plug screwed into the bottom of the fuze body. A paper disc covers the aperture in the magazine cover, and a hole leading out of the base plug is sealed with another paper disc. The magazine contains a gunpowder charge of about 30 grains.

OPERATION:

The safety pin is removed manually when the flare is loaded aboard the aircraft. Upon release, the firing plug is withdrawn, pulling back the striker against its spring until the two balls are clear of the retaining plug. The balls then fall away, and the striker is forced by its spring against the detonator. The flash passes upwards through the firing channel and ignites the powder in the lower groove of the fixed delay ring. This fires the long pellet connecting the upper and lower grooves, which in turn ignites the pow-der in the upper groove. After a time interval determined by the position of the short igniter pellets in the setting ring, these pellets are fired by the powder in the upper groove. The flash from the short igniter pellets passes through the hole communicating whith the annular grooves in the setting ring and spigot and ignites the long igniter pellets in the spigot. The flash from these pellets passes downward through the flash channel in the spigot and the fuze body fires the gunpowder charge in the magazine.

REMAKRS:

1. No. 35 Mk. I: identical with the Mk. IV, except that the fixed delay ring is gradua-ted from 3½ to 17, representing seconds of delay. The magazine contains 50 grains of gunpowder.

2. No. 35 Mk. I*: identical with the Mk. I, except that the gunpowder charge in the magazine is reduced to 30 grains.

3. No. 35 Mk. II: identical with the Mk IV, except that the gunpowder charge in the magazine is 50 grains.

4. No. 35 Mks, II* & III: substantially identical to the Mk. IV fuze.