DESCRIPTION. The Zt.Z. (89)D fuze is similar to the Zt.Z. (89)B. On release from air-craft, the igniter is fired electrically, the clockwork mechanism started and the safety shutter released in an identical manner with that of the Zt.Z. (89)B. The timing disc, operated by the clockwork mechanism, rotates to bring the timing disc slot in line with the nib of the striker release arm. When this position is reached, the striker rotates, due to the action of the cam surfaces of the striker projection and steel pillar acting under the influence of the striker spring. When the striker projection is clear of the steel pillar, the striker spring forces the freed striker on to the detonator cap. (See fig. 180.)

REMARKS. This fuze has never been recovered in a container and therefore the types in which it is used are not known.

Figure 180 – (89)D Clockwork Aerial Burst Fuze