A very clear instructional film for Royal Air Force armourers, with excellent close up photography. Fuzing is the stage where the individual components of a depth charge are assembled prior to their loading into an aircraft. The need for the greatest care is emphasised when handling these large explosive devices.
“Fuzing 250lbs (pound) depth charges with mark XX pistols”:
Film opens with tradesmen loading un-primed 250lb depth charges into a wooden barge adjacent to the loading jetty; the pistols are loaded separately into wooden racks; primer springs; primers and detonators also in separate wooden boxes; tail fins for the depth charges; finally, the special tools required for fuzing. The tradesmen board the motorised barge (583 RAF) sail to the open water, moor to a buoy well away from human habitation and artefacts, thus minimising damage in the event of an accidental explosion.
Cut to nearby Sunderland waiting to load eight depth charges from the barge. The tradesmen proceed to assemble the depth charge components; the primer spring is screwed into the body of the depth charge; a live primer fitted to the primer tube; the detonator carrier removed from the pistol; detonator fitted and replaced in pistol; pistol screwed into the primer tube of the depth charge. Each stage of this assembly process is explained in great detail. Now armed, great care is required as the loading proceeds. The transit pin removed; the rotating vane in the tail fin checked for operation; the tail fin fitted to the depth charge body; a safety wire is attached to the arming plate; ‘fuzed’ chalked onto the body. Fuzing complete, the tradesmen replace the depth charges in the barge, sail back to the jetty and hand over to the waiting bombing up crew.