CBU version 2

[nbk2000]

Original picture was deleted by free host. Attached archived copy.

[mongo blongo]

Does CBU stand for Cluster Bomb Unit? Since there is a centrifugal safety switch it's meant to be fired from some sort of gun right?

[nbk2000]

Sorry for the delay, but I wanted to get the picture posted before I went to bed last night.

Anyways, I've been doing some more study about the design and construction of cluster bombs and the submunitions that go in them, as part of the DVD.

Originally, I thought of using empty soda cans as forms to make the submunitions in, being of the appropriate size and shape.

But then I re-read my own article from an RTPB perspective, and realized that anyone with the finances to fly a plane, and the will to drop a CBU on a crowd of people, would be willing to invest the proper time and money to do a "bang-up" job of it. (sorry for the pun)

So someone who isn't me redesigned the CBU submunitions with that in mind.

Firstly, the exterior shell is made of thin stamped steel, as obtained from (find the link yourself), which (someone) was kind enough to provide here on the Forum.

Next, the interior electronic fuze was inspired by two different toys, imported from china. One was a personal fan that had the blades light up in different patterns, the other was a yo-yo waterball that blinks when you smack it.

Well, Google is a wonderful thing, because searching for "centrifugal switch china" yeilds a nice source of dirt cheap switches that will activate at different RPMs. Samples are obtained of 1,200 RPM switches, which are about the thickness of a matchstick, and half as long.

Slightly different switch detects strong impact.

By combining these on a small PCB board with a capacitor and an electric detonator, you get an centrifugally armed-impact activated electronic fuze. :)

The steel shell is lined with 1/4" steel slingshot ammo, rather than BB's, and filled with a cast explosive. The inner fuze sphere (made from small polycarbonate shells obtained from hobby store) is pressed into the explosive while still soft.

After setting, the electronic fuzing is inserted into the inner sphere, the other half of the inner sphere (with the detonator hole) snapped into place, and the other half of the explosive filled submunition is superglued into place.

The steel shell is then inserted into a plaster mold and encased inside a polymeric rubber coating of 1/2" thickness. This is a high durometer rubber, like superball, which provides an airbursting rebound.

The mold has been made by laying strips of modeling clay cut into the shape of flettner (SP?) rotors and laying it on a sphere of suitable size. This is then cast into a plaster mold.

When the submunition is encased in the mold, and the rubber cast around it, the rubber takes the shape of the rotors, which provide the aerodynamic drag that provides spin to arm it.

The way the submunition works is that, when dropped, the rotors cause the submunition to begin spinning around an axis. This axis of rotation is in line with the centrifugal switch. The switch engages once it reaches a high enough RPM, allowing a current of electricity from the battery to begin charging the capacitor.

After a few seconds of spinning, the cap is fully charged, and now contains enough juice to function the detonator, when the impact switch detects impact with the target.

The impact switch is mounted so that it is parrallel with the axis of rotation. Thus, it's effectively not moving while spinning about the axis, but any impact off-axis will cause it to function.

Upon impacting, the rubber and high spinning, cause the submunition to rebound into the air a few feet before the fuze has time to explode, causing a near-surface airburst. This greatly increases effectiveness against personnel.

Combining the two different types of switches, in addition to the need for several seconds to charge the capacitor to function the detonator, provides a much higher degree of safety for the manufacturer and (presumed) pilot, since it's highly unlikely to arm and function from even rough handling.

Enhancements would include the inclusion of incendiary pellets of the type described in any number of patents, to cause fires among suitable targets.

Now, with the development of low-cost GPS guided cruise missles (LLCM), the whole thing falls together.

Imagine a scenario where Allah Rag-head launches a LCCM targeting the tarmac of a busy international airport during a holiday rush.

The LCCM is optimized for payload, since it doesn't have to fly hundreds of miles to hit its target, so fuel can be replaced by submunitions.

Each submunition is loaded with 3/8" steel shot, with a matrix of incendiary pellets mixed into the high explosive filling.

The LCCM overflies the tarmac, where a half-dozen 747's and 777's are lined up, filled to capacity with passengers, and fully loaded with fuel for the long flight ahead.

Flying parrallel to the tarmac, the LCCM begins to eject its payload of 100 submunitions, right on top of these fragile flying gas tanks. :)

Each plane, having a surface area the size of a football field, are impossible to miss. Each one catches at least a half dozen submuntions on the fuselage and wings.

The wings, made of thing sheet metal, are shredded by the direct impact of an explosive device on the wing, with dozens of steel balls ripping holes through the fuel cells, turning them into leaky seives.

This wouldn't be so bad...if it wasn't for the flaming zirconium/teflon incendiary pellets that happen to be propelled into the fuel spills...burning at 4,000°F...at the same time. ;)

Several of the jets are turned into giant crematoriums, with the majority of the passengers being burned alive in the massive fireballs that ensue from the strike.

Cost? Tens of thousands and a few months.

Results? Priceless!

[nbk2000]

One thing that would help these be more effective is a random-decay timer for 10% or 15% of the CBU's that are missing their impact fuzes.

This turns them from into random time-bombs scattered amoungst the debris, complicating rescue efforts, as the CBU's will continue exploding at intervals during recovery operations. :p

Thing that always stymied me was the complication of timers and how to get them randomized.

Well, thanks to one of the books from that jihadi site, I got the answer.

Use a 4-way mechanical tilt switch (http://www.photologic.ca/swballsm.jpg), and solder a resistor to each of the four legs of the switch. The resistors are in a range that, when connected to a relay-decay timer, causes the relay to function between a few minutes to an hour.

Then, after dispersal, each CBU clearance delay unit will have 4 different time delays built-in. Which one is used depends entirely on which way the unit rests. :)

[FUTI]

NBK you are the pure evil genius. If you could use such amount of brain "processing" time to earning money for some big firm...I'm sure I would see your name some time in the future among richest 100 in USA.

[Jacks Complete]

Slight snag with that picture: I get the message Attention: **** Free Hosting Customers

On March 1st, 2004, **** discontinued free Web hosting plans. If you had a free hosting account and did not upgrade, your account has been taken offline. when I go to the hostname.

[nbk2000]

Of course it's gone, it's been 4 years. :p

The picuture is irrelevant now anyways, as the idea of the random decay timer was the point, but I've attached anyways to the original post.

[Jacks Complete]

Hahaha, ok, my bad. I thought it was a new thread, but now I see FUTI bumped it. Still, it's a good idea.

As ever, the scope of useage is more important than the weapon itself. I don't think I'd bother with a LCCM for this scattering application, but itstead go for a giant cannon, of the type the IRA developed from gas canisters. Load a few of these up, and aim roughly (like a shotgun mortar) at your target area(s) and set timers to fire them all within a few minutes.

The scattering and the randomly tripping delay charges would be good, and then a final mortar could trip a few hours later, for maximum effect against the troops securing the area.

[sdjsdj]

Excellent idea, but I have my doubts abouth the effectiveness of the random-decay timed submunitions; as a battlefield weapon (I believe MLRS saturates an area with something like this?) troops are trained to deal with it - once they realise what it is, every individual within a mile of the attack epicentre will be wearing enough ceramic/kevlar to survive the detonation of a submunition of optimal launch size, and giving any suspicious-looking objects a wide berth.
With a shorter-term fuse (minutes not hours), you may, however, be able to target survivors and the first few to respond - probably unarmoured rescue crews - who will be vulnerable.