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Petard?

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Is this a correct use of the term, and if so should it be used in the first sentence of the definition?Smile4Chomsky (talk) 12:56, 13 December 2008 (UTC)[reply]

MRE's?

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"Because they use explosives to form a solid copper penetrator instead of using an explosive blast or metal fragments, these charges are extremely dangerous, even to the new generation of MREs (which are made to withstand an anti-tank mine), and many tanks.[9]" MRE's stand for Meals Ready to Eat and the link directs as such, what does that have anything to do with armor or EFP's? —Preceding unsigned comment added by 92.48.72.35 (talk) 17:52, 19 October 2008 (UTC)[reply]

Revision as of 22 june 2007

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I find that the graf about MEFP, SEFP, etc adds a great deal of jargon, much redundant information, quite a lot of unnecessary technical detail, and very little relative value for the non-obsessed reader; anybody agrees/disagrees?--Victor falk 23:46, 26 June 2007 (UTC)[reply]

I dunno, I think its alright... Tmaull 03:42, 27 June 2007 (UTC)[reply]
It is allright, after thinking. But something bothers me about the structure of the article, I think the "difference from shape charge" should be rearangered, maybe divided into several sections or subsections. Or maybe both current sections into practical (use in weapon systems & ied's, technical details) and theoretical sections. What do people think?--Victor falk 21:42, 1 July 2007 (UTC)[reply]

EFP's as a special type of shaped charge?

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"An explosively formed penetrator (EFP), self forging warhead or self forging fragment is a special type of shaped charge that is designed to penetrate effectively at long range."

I find it questionable to describe EFPs as a "special type of shaped charge".

Early in the article it states, "A conventional shaped charge has a generally conical metal liner that projects.... An EFP, on the other hand, has a liner in the shape of a shallow dish."

The purpose of the metal liner inside the conical cavity of the shaped charge is to add greater mass to the "jet" enabling greater penetration. It should be noted that these liners are far thinner than the disk found on EFP/SFF's.

The article later states, "The charges are generally cylindrical, fabricated from commonly available water or oil pipe with the forward end closed by a concave copper or steel disk (liner) to create a shaped charge."

This does absolutely nothing to create a shaped charge. The key thing is consistency in the metal of the disk, consistency in the placement and composition of the explosive charge and that the explosive charge is center primed. Read some of the patents that are published about EFPs.

When we were shown how to make expedient/improvised explosive devices while I was on active duty in the early 90's we were shown how to make something called a platter charge.

Go to [1] and search down toward the bottom for "Figure 13-16. Platter charge"

"PLATTER CHARGE The platter charge (Figure 13-16) consists of a suitable container that is filled with uniformly packed explosive and placed behind a platter. The platter is metal (preferably round, but square is satisfactory) and weighs 1 to 3 kilograms..."

In a nutshell the term "shaped charge" should primarily apply to devices where the actualy "shape" of the explosives is the primary determinant in the devise's effects.

The platter charge should be called just that a platter charge - unless there is a more specific and descriptive name. The projectile that results from its detonation should be called the Explosively Formed Penetrator or Self Forging Fragment. —The preceding unsigned comment was added by 68.226.49.191 (talk) 11:07, 22 February 2007 (UTC).[reply]

  • What is opposite of shaped charge? Bulk charge! EFP is not bulk. Both EFP and old-fashioned shaped charge have special shapes to focus effect of explosion, unlike bulk charge which explodes equally in all directions. Also, Walter's book on shaped charge (see Refs) has a small chapter on EFP. That book also discusses charges in between shapes of old conical shaped charge and EFP, like hemispherical charge. In platter charge, shape is also important--don't put platter upside down, won't work! Also, that Global Security site you mentioned has another page with EFP and shaped charge together, but not bulk charge. It says EFP liner can be a wide angle cone, logical extension of concept of old narrow conical shaped charge.--MajorHazard 11:25, 2 March 2007 (UTC)[reply]

Iran Connection

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Should the current claimed connection between Iran and EFPs in Iraq be discussed? The talking heads claiming a link to Iran cite that Iran is especially adapt at making EFPs. They don't give real citations though. I wouldn't consider anything that Michael Gordon (or the current administration) says to be of a high enough quality to be on wikipedia either.

It doesn't seem right to go into political matters in the body of this technical article. On reflection, do you not agree? John Wheater 07:45, 27 February 2007 (UTC)[reply]
I agree wholly with John Weather, political controversies do not belong in a technical article, especially when they are more than two thirds of the article and furthermore degenerate into an edit war. Victor falk 07:48, 22 March 2007 (UTC)VictorFalk[reply]

I have commented on this in the Section titled Alfred Herrhausen, below. Lorinhobenson 13:38, 31 July 2007 (UTC)[reply]

Maybe some clarification necessary

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I found one sentence in the article a little bit missleading. Quote: "It can easily punch through the protection of light- to medium-armoured vehicles, to deliver a wide spray of fragments of liner material and vehicle armour backspall into the vehicle's interior, injuring its crew and damaging other systems." Now in my opinion it should be clarified, that these weapons are dangerous for heavy armoured vehicles and even main battle tanks like the Challenger 2 (the tanks deployed in Iraq carry additional armour and weight about 70 tons, claims the source). The Guardian reported an attack on a Challenger 2 with an EFP, resulting in a heavily wounded driver. http://www.guardian.co.uk/uk_news/story/0,,2064110,00.html This article states some details on the vector of attack: http://commentisfree.guardian.co.uk/robert_fox/2007/04/king_or_country.html Quote: "The charge was aimed through the front of a main track, a vulnerable point in any such vehicle and under the driver's compartment at the front of the tank - which should have some of the best protection by armoured plating." It's also claimed that several Abrams tanks have been destroyed in central iraq, but I'm not shure about these information. Maybe someone could look into it.

Mobility killed, yes. Catastrophically killed, no. Mostly what RPGs and the like did was just put blackened gouges in the armor.--LWF 12:52, 27 April 2007 (UTC)[reply]

As I understand, EFPs cannot pierce heavy armour, e.g. the front armour of a MBT's turret; as the quote says, it was hit in a weak spot. Just because you can destroy a tank by throwing a grenade in open hatch, you don't say grenades are a danger to heavy armour.--Victor falk 13:09, 30 April 2007 (UTC)[reply]

SADARM and other weapons were designed to kill tanks (heavy armour) with EFP. Maybe they don't work?--MajorHazard 17:54, 25 May 2007 (UTC)[reply]
Aerial anti-tank EFPs attack from above, where the armour is only light or medium... --Victor falk 19:34, 27 May 2007 (UTC)[reply]
This is precisely crux of needed clarification. MBT is of class "heavy armour", but EFP can defeat from top or side or rear (some EFP fired from ground) or bottom (EFP in mines). Exact statement is that EFP *weapons* (diameter ~150mm) can perforate all armoured vehicles except thickest front armour of MBT. Some *IED* EFP are bigger (London Times shows 250mm diameter!!), perhaps can even penetrate very thick armour of tank. What happens after EFP perforate to inside vehicle depends on what it hits, maybe catastrophe (hit explosive, kill all crew) or not. Mention of RPG here is not relevant, don't have EFP.--MajorHazard 07:48, 28 May 2007 (UTC)[reply]
You're right. I have removed "light and medium". --Victor falk 07:33, 30 May 2007 (UTC)[reply]
I found this interetsting factoid..:

Weapons will also be tailored to the particular operation. If a directional explosive is needed,the terrorist could make use of available military models of anti-tank and anti-personnel mines. Conversely, the terrorist may determine that a mine would be detected by the target'ssecurity force en route to the attack, and he therefore needs to build or obtain an alternative device. To illustrate, even counting the warheads of anti-ship cruise missiles, there was not a readily available weapon for the attack on the USS Cole. No one manufactures a half-ton C-4 platter charge configured to fit in a small boat, but that was exactly what the terrorist's plan required. Therefore it was exactly what the terrorist group built. Additionally, Operation Iraqi Freedom has demonstrated the terrorists' ability to construct a variety of IEDs that are effective, yet are easily emplaced and difficult to detect by military forces. source: (pdf): http://www.au.af.mil/au/awc/awcgate/army/guidterr/app_c.pdf --Victor falk 22:32, 11 June 2007 (UTC).[reply]

Alfred Herrhausen, Hezballah, and Iran

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I have requested a citation for the claim that Alfred Herrhausen was killed by and EFP. I am pretty sure that it was actually a platter charge, which is similar, but not the same. Also I have requested a citation on the claim that Hezbollah used them in the '06 war. I am pretty sure that there is something out there, but I don't know where. If Hezbollah is using actual EFP's, and not platter charges, then we return to the question of where they get them from. It is a germane question from a technical perspective, because either these devices are easy to make, and can be assembled readily, or they require a degree of proficiency. If the former, then surely they are the largest emerging threat. If the latter then they are usually a product of a state or a professional organization. Which in turn, with respect to Hezbollah, raises Iran.

I have a proposal that should be both verifiable, and not violate the NPOV rule. Perhaps a section on countries that are developing EFP's could be added. Then reports stating that Iran is passing such weapons to Hezbollah, or insurgent groups within Iraq could be brought up as just that, reports. If we begin discounting reports because we dislike their politics, we run the risk of violating the NPOV, and simultaneously eliminate our greatest source of information. After all, if we through out all information from 'this administration' then what about meteorological data, or overhead imagery, or highway closures for that matter. We would then only be able to get information from opposition, which would clearly be a violation of NPOV. If we present reports, as reports, we should be fine.

Lorinhobenson 13:37, 31 July 2007 (UTC)[reply]

From earlier discussion, it appears that platter charges are the same as EFPs. Or rather that a platter charge is an undetonated EFP.Tmaull 17:00, 31 July 2007 (UTC)[reply]
Yes, platter charge is improvised EFP! See how platter charge comes back to this article.--MajorHazard 21:15, 31 July 2007 (UTC)[reply]
As convincing as it is that there is a Wikipedia reroute from platter charge to explosively formed penetrator, a platter charge is not an EFP. Without getting into too much detail, the difference is the usage of the Misnay-Schardin effect. A platter charge is flat, therefore when it explodes it sends its face plate forward at a 90 degree angle to the mass of the explosive. It is therefore projected straight forward, and largely unchanged, rather like a coin that you might flip off of your thumb. This has been around for a long time, and it very deadly in its own right. However, the EFP is shaped in such a way that the energy from the explosive (in accordance with the Misnay-Schardin effect) does not distribute evenly, and instead the face plate of the EFP deforms from a flat plate to a projectile, ideally shaped more like a sabot that is fired from a tank cannon, than the flat plate which it originally was. This is illustrated very well on the page, itself. The EFP is special because done correctly, it is much more effective against heavier armor. In other words, it forms a penetrator from the explosion, or it is an exposively formed penetrator, hence the name.
Now this is often not particularly relevant, because while the MS effect is predictable, the reaction of imperfect metals is not. Therefore, many would-be-EFP's turn into platter charges, for varying reasons, and that is also why most functional EFP's are not homemade, but are made in a place with industrial grade equipment, especially metal presses. The point of the original comment was that, I am fairly sure, given its time frame, and the advent of the EFP, that the IED that killed Alfred Herrhausen was intended as a platter charge. Unless we find some documentation otherwise, we should remove it as an example of an EFP. After all there is no shame in being a deliberate platter charge. :-) Lorinhobenson 19:02, 1 August 2007 (UTC)[reply]
Documentation that platter charge is improvised EFP? US Army training handbook, A Military Guide to Terrorism in the Twenty-First Century, 2005 says on page E-10: "Explosively formed projectiles (commonly called platter charges or disk charges)." (A little info on Herrhausen on following page.) Also, Misznay (note how he is spelt) and Schardin worked during WWII, so Misznay-Schardin effect is around a long time too, almost as long as shaped charges with metal liners.--MajorHazard 22:58, 1 August 2007 (UTC)[reply]

Fair use rationale for Image:ExFiPro-balanced.jpg

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Image:ExFiPro-balanced.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

Please go to the image description page and edit it to include a fair use rationale. Using one of the templates at Wikipedia:Fair use rationale guideline is an easy way to insure that your image is in compliance with Wikipedia policy, but remember that you must complete the template. Do not simply insert a blank template on an image page.

If there is other fair use media, consider checking that you have specified the fair use rationale on the other images used on this page. Note that any fair use images uploaded after 4 May, 2006, and lacking such an explanation will be deleted one week after they have been uploaded, as described on criteria for speedy deletion. If you have any questions please ask them at the Media copyright questions page. Thank you.

BetacommandBot 03:03, 1 October 2007 (UTC)[reply]

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The recently added text starting "An EFP eight inches" seems to be a direct copy of the Washington Post footnoted article http://www.washingtonpost.com/wp-dyn/content/article/2007/09/30/AR2007093001675_5.html. Does this meet fair use requirements? Burt Harris (talk) 21:05, 26 July 2008 (UTC)[reply]

Two sentences (actually one sentence with another in parenthesis) doesn't rise the level of copyvio. It needs to be a larger portion of the article (this Washington Post article, BTW, is 5 pages long). I appreciate your eagle eyes, but this case is a little overzealous. I think Wikipedia's interests are covered here.
Either way, it's now in block quotes as an extra precaution (read more about policy here: Wikipedia:Plagiarism, Wikipedia:Copyrights, Wikipedia:Non-free content), a little overboard in my opinion but whatever it takes so everybody is comfortable. If we weren't allowed to use any material whatsoever from previous articles all of Wikipedia would become original research and all of Wikipedia would violate the Wikipedia:No original research policy. Copyright law allows for taking small parts from other sources (especially for non-profit) as long as you aren't stealing the essense of their work and claiming it for yourself.
"Brief quotations of copyrighted text may be used to illustrate a point, establish context, or attribute a point of view or idea."-Wikipedia:Fair_use#Text IraqVet225 (talk) 22:33, 27 July 2008 (UTC)[reply]
Copyright issues aside, I'm not sure that anyone claiming a .50 is one of the most devastating projectiles on the battlefield is a useful source. The comparison was valid, but that statement is just silly.Mzmadmike (talk) 05:29, 10 December 2008 (UTC)[reply]

need in-article explanation for standoff distance

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After going off and reading the linked disambiguation article on standoff, I have not the slightest clue what this is supposed to mean in this article. How far away, exactly is "stand off" distance? 1 meter? 10 meters? Is it the distance you can run before whatever detonates? DMahalko (talk) 02:46, 19 January 2010 (UTC)[reply]

Invented in WWII?

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The article says explosively formed penetrators were formed in WWII yet the citation does not go to a specific article, there is no further information and I have never seen any source saying that EFPs were used in WWII. Clarification needed. Kbog (talk) 03:46, 1 October 2012 (UTC)[reply]

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--Gary Dee 18:32, 8 July 2013 (UTC)[reply]

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The example given from The Terminal List is excessively descriptive of the plot of the show. Anyone coming to this Wikipedia article for encyclopedic information on EFPs may be unintentionally exposed to plot details that do not substantially increase understanding about EFPs.

Simply stating that an EFP was an important plot element of The Terminal List might be appropriate for this article, but not the extra details about how and why it was used. 47.6.83.115 (talk) 20:06, 28 August 2022 (UTC)[reply]

Removed per WP:MILPOP: "'In popular culture' sections should be avoided unless the subject has had a well-cited and notable impact on popular culture." BilCat (talk) 23:10, 28 August 2022 (UTC)[reply]
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