Mine Detection

[tar]

An AP mine could do some damage to a Kubelwagen for sure. It would probably do nothing to a tank, but the tank should at least set it off.

Of course, the various military forces thought of this as well. In addition to the mixing of mine types, the detonators on many AP mines were set to not detonate if too much pressure were applied. This was precisely to stop the clearing by armored vehicles approach. The weight of the triggering object had to be closer to that of a man, rather than a vehicle.

[ASL Veteran]

Originally posted by tar:

Of course, the various military forces thought of this as well. In addition to the mixing of mine types, the detonators on many AP mines were set to not detonate if too much pressure were applied. This was precisely to stop the clearing by armored vehicles approach. The weight of the triggering object had to be closer to that of a man, rather than a vehicle.

Wow, that is certainly fascinating .... although I have to admit that in looking at all the various fuzes available I can't see how they could pull that one off and still have an active mine afterwards. There is nothing in the fuze designs that I'm looking at that would indicate that what you are saying is even possible to do.

A mechanical fuze has a spring which drives a striker against a percussion cap, which then fires the detonator. This can be accomplished through a pull firing device, a tension release device, a pressure release device (after a weight is removed from the fuze), or a pressure firing device. The first two fuze types are used with tripwires primarily, and the third is used with anti handling devices. Here is a description of the US M1A1 pressure activated device:

The M1A1 device is pressure actuated. Pressure is applied directly to the trigger head or can be transmitted via the three pronged pressure head. A pressure of 20 pounds or more, applied to the trigger head compresses the striker release pin spring and pushes the release of the pin inward. When the enlarged portion of the keyhole shaped opening in the release pin is in line with the spindle, the firing pin is released. The spring loaded firing pin then fires the primer and, in turn, the standard base.

I suppose that it would be theoretically possible to make a fuze in such a way that too much weight would crush the firing pin or the striker and disable the mine, but I can't see any way that you could put an upper limit on the weight required to activate the firing pin. In the case of the M1A1 the amount of weight applied beyond the minimum required 20 pounds would be irrelevant if you were using the prong since the striker is shown laying on it's side adjacent to the mine with the prong pressure head at right angles to the firing pin (and sticking straight up to the surface of the ground).

Can you describe how you would set a pressure fuze to go off within a weight range rather than one being activated when a weight limit is exceeded? I have access to diagrams and descriptions of Modern (well, 1985 anyway) US and Soviet fuzes so if you could explain how this is accomplished using one of those fuzes it would be helpful since I could follow along and visualize it.

The use of stronger springs or metal to be sheared will force more pressure to be used to activate a mine, but to have a spring or a shear strip that will only compress / shear within a weight range sounds ... improbable to me. It would require a spring that is strong enough to prevent activation at the lower end of the weight spectrum, weak enough for activation within a specified weight range, and then suddenly the spring would have to be too strong to be depressed when the weight is greater than the specified range. Sounds like some interesting metalurgical properties. :eek: