FUZING

COLOR

CONTENTS

TAIL NO.

OVERALL LENGTH

DIAMETER

TAIL LENGTH

TAIL DIAMETER

TOTAL WEIGHT

DESCRIPTION:

This cluster comprises two faggots of 79 bombs each, the bombs in each arranged nose to tail and with their safety plungers inwards so that they are all depressed. The bombs are held in place by a front end plate and a rear end plate, a top beam and a bottom beam, four wooden slats, tensioning straps and a retaining bar having lateral pins which engage tabs in the tensioning straps. A shear wire passes through a bridge and the retaining bar at a position near the end plate. A channel secured to the rear end plate supports a fuze adapter, the outer end of which is closed by a transit plug fitted with a leather washer. Inside the adapter is a piston through which is a pin ar-ranged to engage the lower end of a pivoted lever. The fuze adapter and the piston are slotted to receive the lever. The upper end of the lever is forked and is connected to the retaining bar. The rear end plate has two dowels for locating the tail in position and a nut welded to the center of the rear end plate to receive one end of a tail tie rod when the tail unit is fitted to the cluster. A nose cover is fitted to the front end plate to decrease the drag of the cluster.

TAIL UNIT:

The tail unit is a shortened drum type tail having a tail cone to which a tail ring is secured by fins. At the base of the tail cone are two holes to fit over the dowels on the rear end plate of the cluster. The tail unit is fitted with a bearing for an arming spindle so that if ist should ever be required to fuze the cluster with an air armed fuze, a suitable arming spindle with an arming vane could be readily fitted. Two windows, one of which is open, are provided in the tail cone. The open window is provided so that when the cluster is prepared for use; the fuzing link connected to the pull-percussion mechanism of the No. 42 Mk IV fuze can be passed through it and be connected to the fuzing unit of the bomb carrier.

SUSPENSION:

A British type suspension lug is fitted to the top beam and tapped holes in the seam are provided for fitting American type lugs.

FUNCTIONING:

When a fuzed cluster projectile is released, the fuze is functioned and after a delay, during which the cluster projectile falls freely, the fuze magazine charge is fired and the products of combustion of the magazone charge force the piston in the fuze adapter against the lower end of the pivoted lever which is thus rocked about its pivot and exerts a pull on the retaining bar of the cluster. This causes the retaining bar to break its shear wire and to be moved so that the pins on the bar disengage the tabs on the tensioning straps. The straps then fly outwards and the cluster disintegrates, the com-ponent parts falling away separately. The individual 4 lb. bombs function on impact.