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BLU-43/B or BLU-44 A/B "Dragontooth" minelet, USA

pzgr40

Well-Known Member
Premium Member
Cutaway model of a US designed and manufactured BLU-43 B or BLU-44 A/B (Bomb Live Unit) Dragontooth, a cluster mine (also called minelet) as used extensively in the Vietnam war during operation Igloo White (1970) , a program to prevent infiltration of NVA and Vietcong personel into the southern part of Vietnam.
The mine is a hydraulicly activated air dropped dispenser mine. Due to its shape borrowed from natures earonautical design of a maple seed- it does not need a parachute, it will descend to the ground rotating on its wing, minimalizing the impact force.
120 Dragontooth mines were packed in a CDU-2/B Cluster adepter, forty of which were loaded into a SUU-13/A dispenser (remains on plane, dispensing cluster adepters), meaning one dispenser holds 4800 mines to form the CBU (Cluster Bomb Unit) 28/A cluster munitions.

Functioning of the mine:
The mine exists of a plastic body, in which an aluminium fuze body with two radial slots is placed. A spring loaded piston with a sleeve is placed in the fuze body which is kept in upper postion by the arming piston retainer (1). The piston also acts as a sort of valve, keeping the liquid sensitizer fluid Propylenediamine/Methanol- (B) apart from the main charge of 9 grams Nitromethane/ Nitroethane (A) by means of two O-rings. The spring loaded firing pin is kept in backward position by two balls which are kept in inward position by the release sleeve surrounding the firing pin housing (green). Connected to this sleeve is an aluminium cup in which the duplex detonator is placed. A spring keeps this assembly in its forward position. A rubber O-ring around the detonator and the inside of the piston sleeve prevents the fluid (B) from leaking away. A sterilizer capsule (C ) is placed in the mine body. This exists of an aluminium cup with a spring loaded sterilisation tablet, kept in place by a disolvable cover.

After release from the CDU-2/B Cluster adepter, the arming tab is released (03), enabeling the arming piston retainer (01) to fall out. This enables the spring to move the piston with the sleeve downward, thereby enabeling the sensitizer fluid (B) to mix with the main charge fluid (A) to form the explosive mix. The fuze and the main charge now form one space filled with liquid. If pressure is applied to the mine body, the hydraulic pressure will push down the aluminium cup with the duplex detonator and the connnected release sleeve, riding its spring downward. This enables the two balls to move outward and release the firing pin, exploding the mine.
The mixing of fluids A & B also enables the sensitizer fluid (A) to start to dissolve the dissolvable cover of the sterilisation tablet. If after activation of the mine it is not stepped upon after a certain time, the spring will push the sterilisation tablet (C ) through the weakened dissolvable cover, forming a chemical self- neutralisation system. However, this does not render inert the duplex detonator.

The main difference between the BLU-43B and BLU-44B is in the chemical proces of neutralisation.
The mine weighs 90 grams.
The mine is activated if 7 kg of pressure is applied.
The mine can be found in the colours olive drab, tan, brown, camouflaged or white. An inert Dummy model of the mine is also available.
The transport safety (02) was removed only after the mine was loaded into the CDU-2/B Cluster adepter.

The Sowjet union made a copy of this BLU mine, the PFM-1. However this mine is larger than the BLU-43B or BLU-44 A/B.

Regards DJH
 

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Thanks US-subs. It is a very interesting design with the two seperated fluids, and the sterilizer capsule that only can work if the sensitizer fluid (B) is added when the mine is activated.
 
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Pzgr40,

If I maybe so abrupt on two things.

1) "Igloo White" is where the Air Force dropped seismic devices over over the jungle, especially on the Ho chin Mihn Trail. These ones were ment for trucks and tanks. In order to pick up some of the rumble of trucks, heavy machines, and Tanks. Some of these detectors were also. where also developed for listening to the enemy if he was walking down the Ho Chi Mihn Trail and were just lolygagging all the way.
Now within the "Igloo White Program" I have some doubt about those devices were ever developed for that program. I could be wrong. But I have Been there, done that, and I'll never go there again, promise.

2) Those dragon teeth were also used for a Recon Team that is running for its life. They were usually used behind the the RT if they had advanced more than 50 meters from the enemy. The Air Force would usualy drop them from side to side, perpendicular to where the enemy was and this would by them time in order to get a "Prarie Fire" extraction.

Just my 2 cents worth.
 
Of cource you may, and I am shurely happy with any added info. The mine was called in conjunction with operation Igloo White on wikipedia in this piece of text:

" The use of Dragontooth mines in Vietnam went largely unnoticed, likely as a product of its essentially classified usage primarily in Laos as part of Operation Iglo white. Production of the system had ceased by 1970, and it was predicted that existing stocks would be exhausted by the end of 1971."

However, of cource I take your word as a first hand wittness for more true.

About your second point; very interesting I did not know that. I only know the M86 PDM, the Persuit Discouragement Mine, in fact a ICM shell delivered ADAM mine fitted with a handgrenade fuze. However this M86 is of a later design.

Thanks for the added info.
Regards, DJH
 
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Check this out for I am thinking you are looking up the wrong item(s).

[ame="http://en.wikipedia.org/wiki/Operation_Igloo_White"]Operation Igloo White - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Flag_of_the_United_States.svg" class="image"><img alt="Flag of the United States.svg" src="http://upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Flag_of_the_United_States.svg/22px-Flag_of_the_United_States.svg.png"@@AMEPARAM@@commons/thumb/a/a4/Flag_of_the_United_States.svg/22px-Flag_of_the_United_States.svg.png[/ame]

Also, they do mention some of the air dropped ordnance, but I believe it was a very small portion of the program. About 90% was about the sensors.

I guess we are both right.
V40
 
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The main difference between the BLU-43B and BLU-44B is in the chemical proces of neutralisation.
The mine weighs 90 grams.
The mine is activated if 7 kg of pressure is applied.
The mine can be found in the colours olive drab, tan, brown, camouflaged or white. An inert Dummy model of the mine is also available.
The transport safety (02) was removed only after the mine was loaded into the CDU-2/B Cluster adepter.

The Sowjet union made a copy of this BLU mine, the PFM-1. However this mine is larger than the BLU-43B or BLU-44 A/B.

Regards DJH



Here are the three colors I know of, followed by the dummy and an East German/Soviet training copy. I've never seen one camouflaged or tan, nor heard of their existance before now. I'd be interested in seeing the reference source material.
 

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Does anybody have info about the chemical composition of the sterilizer stick?
 
Sorry about that, I tried a cut and paste from wikipedia but the hyperlinks went wild. Let me try again. I'm trying to rant about people using Wiki as a technical reference.

Wikipedia is a nice starting point for preparing to do research, but with all due respect, it is not research. It is not a technical reference and should not be used as one. Any clown can put stuff on Wikipedia knowing nothing and not being held accountable. Just because you read it there means absolutely nothing. This is one of the flaws of the internet. You have numerous people, on this site as well, who read something on Wiki and treat it like it is gospel, then pass it on to others as the truth. Here is the truth, from Wikipeidia itself, keep this in mind when you use them as a reference:

Wikipedia is written collaboratively by largely anonymous internet users who write without pay. Anyone with internet access can write and make changes to Wikipedia articles. Users can contribute anonymously, under a pseudonym, or with their real identity, if they choose, though the latter is discouraged for safety reasons.

Every contribution may be reviewed or changed. The expertise or qualifications of the user is usually not considered.

This comes from "About Wikipedia" on the left side of the page you linked to.

I realise that there is not a lot of info quickly available, but too many people are not doing real reasearch anymore, they are taking the easy way out and using trash references. Don't be that person.
 
I agree completely, Wiki can be a starting or entertainment reading point for identifying an item or historical event, however should not be quoted without reservation when reputation or technical accuracy are at stake. Several times I have found inaccuracies, outright speculation and old wife's tales on Wiki.
 
Blu44a/b self destruct

THE BLU44A/B(SELF-DESTRUCT) HAS A NOMIAL LIFE OF 84 HOURS, AND SELF DESTRUCTS BETWEEN 14 AND 35 DAYS. THE SELF DESTRUCT CAPSULE OF THE BLU 44A/B CONTAINS CUPROUS CHLORIDE AND SODIUM BOROHYDRIDE. THE SODIUM BOROHYDRIDE REACTS WITH THE METHANOL AND WATER IN THE EXPLOSIVE, TO PRODUCE HYDROGEN GAS. THE HYDROGEN GAS CREATES SUFFICIENT INTERNAL HYDRAULIC PRESSURE TO FUNCTION THE FUZE. IF THE MINE FAILS TO SD, HYDRAULIC PRESSURE WILL RUPTURE THE MINE HOUSING OR FORCE THE HYDROGEN GAS OR THE EXPLOSIVE MIXTURE OUT THROUGH A SMALL HOLE (FLAW) IN THE MINE. IF THE EXPLOSIVE MIXTURE REMAINS IN THE MINE, STERILIZATION WILL BE AFFECTED BY THE CUPROUS CHLORIDE.

FILLER; FUEL; NITROMETHANE/NITROETHANE 8grams

SENSITIZER; PROPYLENE DIAMENE/ METHANOL 1 gram
 
I'm doing some work on identifying the sensors used during this and other operations. Not a lot of straightforward info so far, and what is held at the AF Air Armament Museum has been muddled a bit (good items, but identification has been mixed up over the years and is in doubt). I've found some good historical photos at the National Archives, I hope to get them sorted in the next month or two and add them to the database.

Not really sure whether to treat them as submunitions or not, they had special dispensers built for some of them, but some models could be tossed out by hand, or they could be dropped individually off the wing like bombs. More to come.
 
Thank you all very much for the info. Especially blu45bob for the info about the SD mechanism and SD times .
Regards DJH

@ US-Subs. I try not to, but it's very hard to get any reliable info about ammo....... Even the TM manuals have mistakes in them. This can be quite a problem when you want to change a piece of ammo into a cutaway model.
 
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Have been to both the old and new AF armament museum at Eglin AFB. I have a picture somewhere with the different versions of sensors lined up. I am surprised that there has not been a better reference for them up to now. I look forward to seeing your results.

Regards,
Alan
 
alan,

that is a great article about Igloo White and very truthful at that. Thanks again.

V40
 
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