Description
The Nose Clockwork Aerial Burst Fuze M144 is similar to the AN-M146, except that it has direct-drive instead of gear-reduction arming, resulting in ejection of the safety block after approximately six to nine turns of the arming vane.
Functioning
Upon release of the bomb, the arming wire is withdrawn from the fuze; the vanes are free to rotate; and the arming pin jumps out. The vanes are positively attached to the arming hub and rotate as one unit. The arming sleeve, which is threaded to the arming hub, is prevented from rotating, since the stop plate attached to it engages the idler-gear pin. However, the arming sleeve moves down as a result of rotation of the arming hub; and after approximately six to nine vane revolutions me arming sleeve has withdrawn far enough for the safety collar to be thrown clear by centrifugal force. The timing disc, meanwhile, has been rotated by the spring-driven clockwork. After 1.5 ± 0.5 seconds of rotation, the timing-disc cam, located below the timing disc (and turning with it), frees the crank-shaped end of the arming stem. The rest of the operation is the same as for the M146.
Hazardous Components
No information about hazardous components.
See Also
Source(s)
MIL-HDBK-146, Fuze Catalog (1982)
TM 9-1385-51, Ammunition (Conventional) for Explosive Ordnance Disposal (1967)
OP 1664, Volume 2 - US Explosive Ordnance (1947)
USNBD - Bombs and Fuzes, Pyrotechnics (1945)
