M86 Pursuit Deterrent Munition (PDM)

[Eodtek]

A question came up the other day on this item and while trying to do a litttle research I realized that there really isn't anything out there to search for other than one little page on global security. I dug through some of my boxes at home and pulled this one out. At some point in time I will go back and replace the trip line covers so it looks complete again but for now, this will do better than the few photos I have seen on the net.

 

[TimG]

Eodtek,

Have you got a schematic or similar for this item that you could post please.

Thanks

TimG.

 

[Eodtek]

I don't have one but the most info you will probably find is here http://www.globalsecurity.org/military/systems/munitions/pdm.htm along with this diagram from a manual.

Mods please feel free to whack the photo if it's too large for browsers. The photo can be found on the linked page.

 

[HAZORD]

The munition is derived from the ADAM mine. Instead of being armed by the ejection from a 155mm Howitzer projectile, it is armed by pulling a safety pin/grenade spoon assembly. It is designed to kill people pursuing. You pull the pin and throw it on the ground. Pulling the pin/spoon activates the internal battery and computer. It waits a brief period and a gas generator functions to release the spring loaded tripwires. No matter how it lays on the ground, some tripwires will extend from the top. The tripwires fan out like the legs of a spider.

When a tripwire is disturbed, it fires a kill mechanism straight up into the air. The Frag ball is slightly smaller than a golf ball. The frag ball is serrated internally and contains a delay fuze which denonates it approximately two feet off the ground.

If the muniton isn't disturbed within a certain time window, it self sterilizes. All of the pertinent information about the functioning of an ADAM mine would apply to this munition.

They were originally issued in an OD pouch that held two munitions, that could be attached to web gear. Typically Spec-OPs type device, Navy SEALs, etc.

 

[Eodtek]

Oh and for those that were wondering about how many types there are out there, I've been able to identify 5 that could be encountered:

1. Live Mine
2. Demonstration Model (The one I show in the photos)
3. Inert Trainer
4. Plastic Resin Training Aid
5. MILES 2000 Simulator

I'm working on getting decent photos of them all.

 

[HAZORD]

Photos of various versions of ADAM mine, which is the basis for the Pursuit Deterrent Munition. Normally the munition would be Olive Drab painted with a black L or S. The L and S stand for long time before self destruct , or short time. The mine in the first 2 photos is an inert test version, so it is painted orange. The third photo is a dummy to show size and shape, and test dispersion from the 155 Howitzer carrier.

The mine starts out as a skeleton of electronics, pneumatics and framework. This framework is shown in photos 4 and 5 and in the next post. The mine is resting on a 25mm link to hold it in the proper orientation for the photos. The white and yellow tubes inside the frame are to carry the pressurized gas to unlatch and launch the tripwires.

 

[HAZORD]

The first 3 photos show various views of the skeleton, the 3rd with the kill mechanism in the center, covered with its surround.

The 4th photo shows an armed dud frag ball and the half of another one. When the ball is launched, the center slider extends to allign the explosive train. If the ball doesn't detonate, it will be found like this in the armed configuration, or if the slider binds the pin will not be extended. Both versions would be explosive duds.

The 5th photo shows the inside of a rusty ball showing the prefrag coining of the metal. The frag balls are resting on the plastic tops for 20 oz soda bottles, for a size comparison and to orient them for the photos.

John

 

[TimG]

Gentlemen,

I can see that on coming to rest there will always be some tripwires in an optimum position. However, what mechanism is there to ensure that the fragmentation ball is fired vertical?

Regards

TimG.

 

[Falcon]

Thanks for posting this, a really interesting device.

 

[HAZORD]

TimG, the answer to your question is buried in the explanation of the mine on the web site listed above, but I will explain it here.

I have attached a couple of photos, the first showing a dud ball with a half and a ball with the surround on it. The second photo is the ball with surround.

The surround looks to be a thick aluminum foil and there is an air gap between the ball and the surround. The unfired mine has a drop of liquid explosive in the air gap, which always sinks to the lowest point. When the mine functions, the liquid explosive detonation under the ball throws it up relatively perpendicular to the ground.

John

 

[TimG]

John,

Thank you very much, making sense now.

Thanks

TimG

 

[HAZORD]

Tim,

You are welcome.

The important thing to learn from this exercise is that the U.S. has a number of submunitions that all use the same frag ball. They can be found as duds and they are dangerous.

I have attached photos of a different submunition (from a 105 Howitzer) that carries the same ball.

John