Airburst munition magnetic induction fuse -reg.

[Zed Zamorin]

Airburst munitions (infantry / artillery) use magnetic induction method to set control electronics in a munition round. But how does magnetic data transfer work in a metallic barrel ? Won't the transmitted magnetic data from the coil located outside be absorbed by the steel barrel ?

 

[kato]

Magnetic induction fuze setters are either mounted in front of the muzzle, i.e. outside the barrel, or program the fuze before it enters the chamber. Fuze setters on the muzzle are more common for automatic cycling, other kinds for single-fire.

 

[Zed Zamorin]

Magnetic induction fuze setters are either mounted in front of the muzzle, i.e. outside the barrel, or program the fuze before it enters the chamber. Fuze setters on the muzzle are more common for automatic cycling, other kinds for single-fire.

Thanks for the reply.
Are you implying that once the distance is locked and projectile launched, the coil at the muzzle passes power and data to the electronics inside the projectile at the instant it passes the muzzle? That seems a bit too fast for the process.
And about programming the fuse before barrel entry, its not possible in UBGLs, is it?

 

[gf0012-aust]

And about programming the fuse before barrel entry, its not possible in UBGLs, is it?

why would you want that level of tech into what is fundamentally a squad/breaching etc... weapon.?

it wouldn't seem to warrant that degree of sophistication....

 

[Zed Zamorin]

why would you want that level of tech into what is fundamentally a squad/breaching etc... weapon.?

it wouldn't seem to warrant that degree of sophistication....

Curiosity.
But really, the tech seems simple, until one dig into the details. And about the importance, its a revolutionary tech.

 

[gf0012-aust]

Curiosity.
But really, the tech seems simple, until one dig into the details. And about the importance, its a revolutionary tech.

I guess my question revolves around the relevance for it for UBGL when fundamentally that weapon is going to be used for less precise reqs

edit:

be that as it may - I'll defer to the resident veggies and wait for their advice

 

[kato]

That seems a bit too fast for the process.

Patents on the topic cite typical transfer times of under 100 µs (we're talking 16-bit words in information passed). For UBGL we're talking 80m/s muzzle velocity at most, requiring quite compact systems of under 1 cm length to pass through while information is transmitted.

The required length is relative to the muzzle velocity of the projectile of course, from a rough look at typical muzzle fuze programmers the above sub-100-µs seems to be a pretty good guess for a generic in-use standard.

And about programming the fuse before barrel entry, its not possible in UBGLs, is it?

Manually loaded artillery uses portable, handheld fuze setters for this purpose. Just to point out one possible technological option.

I guess my question revolves around the relevance for it for UBGL when fundamentally that weapon is going to be used for less precise reqs

There's at least one company (ST Engineering) that sells 40mm LV airburst for use in underbarrel grenade launchers with a rail-attached compact programming unit that also includes a laser rangefinder.

The method of fuze-setting used in that case - presumably a slip-on ring for the muzzle with the fuze-setter - is not publicized at all though. Alternative options such as remote programming by radio are rather unlikely since according to company literature the ammunition itself does not contain an electric power source (relevant for shelf life). The ammunition is also explicitly programmed "after firing".