USNBD, Bombs and Fuzes; Section III - Bomb Fuzes: AN-M139A1, AN-M140A1, M139, M140

U.S.N.B.D. - UNITED STATES - BOMBS AND FUZES; PYROTECHNICS

SECTION III - BOMB FUZES

DATA:		U.S. ARMY NOSE FUZES
		AN-M139A1 AN-M104A1
BOMBS USED IN	All bombs receiving
	AN-M103A1. See page 159
FUNCTIONING	M139, AN-M139A1 instan-
	taneous or .01 second	M139
	delay alternative settings.	M140
	M140, AN-M140A1 instan-
	taneous or 0.25 second	MECHANICAL IMPACT
	delay setting.
ARMED CONDITION	When safeyt discs are out.
FUZES USED WITH	AN-M100A2 Series
ARMING TIME	Instantaneous setting, 330 vans revolutions.

	.1 sec. delay setting, 220 vans revolutions.
VANE SPAN	6 in. (2 vanes)
MAX. BODY DIAMETER	2.7 in.
OVERALL LENGTH	7 in. (with booster)
MATERIAL	Cadmium plated steel with some brass parts

GENERAL:

The M139 and M140 are identical in construction to the standard AN-M103 with the exception that the amount of the delay element has been changed to decrease the functioning delay time from .1 second (AN-M103) to .01 (M139) or 0.025 (M140). All fuzes have the alternative instantaneous setting.

In order to distinguish these fuzes from the AN-M103, the vane cups have segments painted on them. One eighth of the vane cup of the M139, and one quarter of the vane cup of the M140 is painted black. These markings correspond with those on the M14 primer detonator. The M139A1 and the M140A1 are the same as the M139 and M140 respectibely, except that they incorporate the widened arming screw found in the AN-M103A1.

OPERATION:

M139, M140: Same as AN-M103, see page 157.

AN-M139A1, AN-M140A1: Same as AN-M103A1, see page 159.

REMARKS:

The AN-M193A1 and AN-M140A1 are current production and replace the M139 and M140 respectively.

All of these fuzes were developed as companion fuzes for the AN-M100A2 series which uses the M14 primer detonators with delays of .01 second or .025 second.

These fuzes are not produced for navel use.