Fox Firepower

Smart grenade seeks out bad guys

Allison Barrie on the new kind of grenade that can find an enemy hiding behind an object, a wall or other would-be covers


What if grenades could locate threats and detonate all on their own?

A new smart grenade can do just that.  With this grenade, soldiers will know with certainty that it will strike its target. 

The U.S. Army is developing the SAGM, Small Arms Grenade Munitions round.

The SAGM is a new kind of grenade that can find an enemy hiding behind an object, a wall or other would-be cover. This is next-generation enhanced grenade lethality.

Why make grenades smart?

When enemies take positions behind, say, low mud walls typical of battle environments like Afghanistan, they can avoid grenade rounds.  In order to most effectively hit a target, soldiers often require a direct line of sight with an M203 rifle-mounted grenade launcher and standard grenades.

A smart grenade could solve this problem.

Just like other “smart” tech that can complete tasks without its user providing instructions, this smart grenade can find its target itself.

When the SAGM is fired, the grenade will recognize its surroundings and the cover used by the enemy for concealment. It then detonates over the target.

The SAGM is an air-bursting grenade and more than doubles the lethality of the current 40-mm grenade against targets that are not directly in a soldier’s line of sight.

The idea is that the 40 mm low-velocity grenade is compatible with the M203 and M320 rifle-mounted grenade launchers used by the Army.

A team at the U.S. Army's Armament Research, Development and Engineering Center at Picatinny Arsenal in New Jersey is developing the SAGM, beginning its research in 2012. ARDEC’s mission is to develop technology and engineering solutions for America's soldiers.

How does it work?

Using an SAGM, a soldier will not need to do any sort of pre-fire programming sequence. The soldier just needs to accurately aim the weapon and fire -- the smart grenade will take care of the rest. While in the air the SAGM will detect walls, without even relying on a range finder. After it passes the wall, the SAGM explodes itself in the air above the target.

To be truly versatile and effective downrange, the SAGM will need to be able to detect and process a wide range of objects people may hide behind. The Army is working on developing a sensor system that will make the SAGM so smart it can do just that.

They’ve made the fuze "smart" by including sensors. The sensors and logic devices scan and filter the environment, detect the obstacle, figure out the best place to detonate and then autonomously airburst the fuze.

The grenade is designed to have three firing modes. The first one is the airburst after it detects the cover where someone is concealed. The next is a default detonation when it hits the target called “point detonation.”  The third mode is a self-destruct feature. This final one is designed to decrease collateral damage and reduce unexploded ordnance left on the battlefield.

The Army has also been developing the XM25 grenade launcher as a direct fire method for these sorts of concealed targets. This weapon uses an on-board laser system to gauge distance to its target. It has a programmable air burst round that determines the distance to its target. The SAGM provides indirect fire.

What’s next?

SAGM is in its third and final phase of development, and is expected to undergo evaluation this summer. It is hoped that the smart grenade will become an official Army program of record this year.

Ballet dancer turned defense specialist Allison Barrie has traveled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at or follow her on Twitter @Allison_Barrie.


Allison Barrie is a defense specialist with experience in more than 70 countries who consults at the highest levels of defense and national security, a lawyer with four postgraduate degrees, and author of the definitive guide, Future Weapons: Access Granted, on sale in 30 countries.  Barrie hosts the new hit podcast “Tactical Talk”  where she gives listeners direct access to the most fascinating Special Operations warriors each week and to find out more about the FOX Firepower host and columnist you can click here or follow her on Twitter @allison_barrie and Instagram @allisonbarriehq.