The fuze is an essential and critical part of any effective munition. They are found in
artillery, projectiles, rockets and bombs, guided missiles, and the new high-tech
precision-guided munitions being developed today. Fuzes are a defense-unique product
with little use in non-military applications.
A fuze provides safe, reliable detonation of a munition at the desired time and place. It
controls safe separation of the munition from the delivery platform and triggers its
detonation. Safety features are built into all fuzes to protect personnel while handling
ammunition during storage, transit and deployment. Additional safety features are
needed to prevent the shell from exploding too soon after deployment, which could also
endanger the gun crew.
Many of the techniques used to design fuzes were developed by Picatinny engineers,
scientists, and technicians. Picatinny's commitment to excellence resulted in safe,
reliable and affordable fuzing systems for the U.S. Army and other services, both U.S.
and foreign. The constant exploration and development of new technologies keeps
Picatinny in the forefront of this highly important field. We have the largest fuzing group
of all the services. In fact, some of the other services look to Picatinny to develop fuzes
for their projectiles since the industrial base supporting such efforts in the past has
dropped off dramatically.
Examples of Fuzes Developed and/or Fielded by Picatinny
Current Artillery Fuzes
The M762A1 and the M767A1 Electronic Time (ET) Fuzes enable the soldier to take
advantage of the latest digital electronic technology. The new fuzes are easier to
operate and more accurate and reliable than their predecessors. The M762A1 is used in
rounds that carry and dispense submunitions such as mines and grenades over the target
areas; the M767A1 provides fuzing for standard high explosive rounds. Both can be
used in all existing 105mm and 155mm weapon systems.
The M782 Multi-Option Fuze Artillery (MOFA) is the latest fuze artillery design and
is compatible with all current 105mm and 155mm bursting artillery projectiles. It
employs state-of-the-art advanced electronic technologies. It replaces seven earlier
fuzes, simplifying logistics and training. MOFA incorporates a proven legacy S&A
device to maintain required safety and reliability and can be inductively set in the
proximity, point detonating, delay or time mode. This multi-option capability reduces
the number of artillery fuzes the U.S. forces have to maintain in inventory.
The M739A1 Fuze is a point detonating (PD) fuze that is used on bursting type
projectiles. The fuze has a rain insensitive nose that allows firing in heavy rain with
reduced probability of early functioning. This fuze may be used in superquick or delay
mode, which are hand settable by turning a screw. The fuze contains a delay arming
mechanism that prevents the fuze, after firing, from arming until a certain distance from
The MK399-1 MOUT Fuze was developed specifically for Military Operations in
Urban Terrain (MOUT). It can be used on both 105mm and 155mm high explosive
rounds. It provides conventional point detonating capability. It also provides a short
delay mode which, coupled with its heavy steel penetrator body, allows for target
effects inside wood, concrete, and brick structures.
The M732A2 Proximity Fuze is a short intrusion proximity fuze that does not require
the removal of the supplementary charge when placed on hand emplaced (HE)
projectiles. Its predecessor, the M732, could not keep pace with the growth in the
severity of the ballistic environment. The M732A2 fuze was designed as an
improvement for compatibility with rocket-assisted projectiles, top zone ballistic
environments and a more consistent height of burst.
Current Mortar Fuzes
The M734A1 Fuze is a state-of-the-art proximity fuze based on Frequency Modulated
Continuous Wave (FMCW) Directional Doppler Ranging (DDR) techniques, similar to
the M782 Multi-Option Fuze for artillery. The M734A1 is very safe and reliable; over
5,000 rounds have been field rested, yielding more than 99 percent reliability. It has
excellent electronic countermeasure hardening, is very accurate and delivers a
consistent height of burst (HOB) performance under all service conditions over terrain
with various reflection coefficients. The M734A1 can be used on all 60, 80, and
120mm high explosive (HE) mortar cartridges and the 120mm White Phosphorous
The M783 Point Detonating (PD) Fuze is a dual safe point detonating and delay fuze
that is based on the M734A1 fuze for commonality of components. This commonality
contributes to economies of scale and results in cost savings in purchasing the
components. M783 is intended for tactical training and can be used during tactical
operations as well. The M783 is qualified for use on all 60, 81, and 120mm HE
cartridges and the 60mm White Phosphorous Smoke Cartridge.
Other Fuzing Applications: Missiles, Mines and Small Caliber
The Stinger Missile is a shoulder-fired antiaircraft weapon. It uses a M934E6 fuze
containing a safe and arming mechanism and dual logic circuits to sense proper launch
profile, S&A rotor position, impact switch, and hard-target sensor interrogation. Upon
impact with a target, a mechanical impact switch enables a timing circuit, resulting in a
preprogrammed firing delay. The hard target sensor overrides the delay and fires the
fuze if an impact threatens breakup of the warhead. A self-destruct circuit destroys the
warhead after 15 seconds of flight if a target is not encountered.
Picatinny is playing a key role in developing Fuzing for the Objective Individual
Combat Weapon (OICW). This shoulder-fired individual weapon will replace the
current M240 and M16A2/M203 combination, which will provide infantry with a
decisive overmatch capability. The fuze for the OICW will have 3 arming modes -
normal, MOUT, and PD backup with the arming distance dependent on the selected
mode. The fire control assembly incorporates a laser rangefinder, ballistic computer,
direct view optics, video sight, electronic compass, thermal capability and a target
tracker. The laser rangefinder measures the distance to the target and converts the
distance. This information, together with the selected firing mode, is transmitted from
the fire control to the fuze through a drive coil wound around the barrel of the gun. The
fuze then determines where to function in the airburst mode by counting turns as it
progresses to the target.
Picatinny has also provided Fuzing for the Objective Crew Served Weapon
(OCSW). OCSW is a lightweight, two-man portable, integrated machine gun system
that combines the firepower of airbursting munitions with optoelectric fire control to
provide all-environment operation and enhanced lethality. It fires 25mm HE
airbursting munitions using a fire control system that automatically transmits the
airburst time to the fuze. This unique technology and design provides accurate fuzing
and, therefore, a high level of effectiveness upon each target. The fuze also has PD and
self-destruct capabilities as back-up functions.