You can contact me at rogercdavies(atsquiggle)

This blog has evolved into a review of historical and modern explosive devices, and responses to them. Links are drawn between historical activity and similar activity in the world today. Mostly I focus on what are now called IEDs but I have a loose personal definition of that and wilingly stray into discussions of more traditional munitions, the science and technology behind them, tactical employment and EOD responses. Sometimes it's just about interesting people in one form or another. Comment is welcome and encouraged but I do monitor it and reserve the right to delete inappropriate stuff. Guest posts are always welcome. Avoid any stuff that makes the enemy's job easier for them.


Entries in IRA (11)


Westminster - an Explosive Past in a 100m Radius

The recent murder of people on Westminster Bridge and the stabbing to death of a policeman at the gates of the Houses of Parliament New Palace Yard have highlighted that the British centre of government and state power has a natural attraction to terrorists.  In my blogs I often look at threads in history of terrorism.  One can find, occasionally, interesting threads in the warp and weft of time, and usually I follow technical threads as far as I can.  But Westminster provides another thread, at right angles, the thread of geography, in a history of explosives and munitions. Bear with me as I recount the explosive history of Westminster - some of which you will know and others you won’t. I have underlined certain specific locations in order to make the point about repeated locations. Westminster is a surprisingly compact place and most of the incidents listed below occurred within about 100m of each other.   For context here's a plan of the explosive incidents in the Houses of Parliament, just about all within a circus of 100m radius:
Locations and Dates - Westminster
1605.   The Gunpowder Plot.  Of course you will know that the Gunpowder Plot targeted Parliament itself, and there is little new I can repeat here. But one aspect is interesting in the light of very modern accusation of “fake news” and “false flag” operations. There has been a school of thought over the ages since soon after the plot itself, that the Gunpowder Plot was a false flag conspiracy dreamt up by loyal royalists to discredit the Catholic opposition. The suggestion is that Sir Robert Cecil, the Royal Chancellor, coordinated a "false flag" operation for political motives, to persuade the public and the King himself that harsh measures were needed to keep persecuting Roman Catholics in England. There is also a suggestion that the gunpowder recovered from the 36 barrels discovered in the Westminster Undercroft had deteriorated so much that it may not have exploded anyway.  In another interesting parallel with today, and attitudes towards Muslims after the recent Westminster attack, King James himself, speaking to both Houses of Parliament five days later made clear that he believed that the plot had been the work of only a few Catholics, not of the English Catholics as a whole. By modern terminology the device was a large timed IED, the timing component being burning fuze.


A report from a few years after the PlotThe Conspirators

1885.     Dynamite Saturday - As part of a dynamite campaign Irish American “Fenian" terrorists planned and executed ”Dynamite Saturday" detonating a number of devices across London. One device exploded as it was being moved by policemen in Westminster Hall.

PCs Cole and Cox are blown up in Westminster Hall

PC William Cole was a London Police officer on duty in the Houses of Parliament on 24 January 1885. He was notified by a visitor, a Mr Green, about a smoking black bag on the steps between the St Mary Undercroft chapel and Westminster Hall, both within the Palace of Westminster. The bag was on the third step of the staircase that lead to the main part of Westminster Hall.  Bravely, Cole picked up the smoking bag and ran up the stairs of Westminster Hall with the intent of moving the bag outside into New Palace Yard. He was preceded by Mr Green who shouted “Dynamite!” to clear the way.  But before he could reach the door,  the bombfuze began to burn his hand, causing him to drop the bag - a second later the bag fully exploded. Cole and his colleague PC Cox, were injured, their clothes largely blown off them  and they lay, blackened in the crater caused by the bomb.  Mr Green was injured in his eyes and his two female companions were “bereft of their upper garments".  Other police and the Deputy Segeant at Arm's wife, Lady Horatia, rushed to attend to the injured. Cole was unconscious, and Cox was "rolling about, talking incoherently and hitting out with his fists although two constables held him down.’  Both officers were described in the politically incorrect language of the time as “black as n*****s”.  Seconds later, another bomb exploded in the empty House of Commons.   In one of those interesting pieces of history (given my interest in the Government’s Inspector of Explosives of the time, Colonel Majendie), Lady Horatia, the wife of the Deputy Sergeant was coopted by the police in the aftermath to help control access to the Hall. Imagine the scene,  the redoubtable Victorian lady assuming the role of gate guardian to a terrorist bomb incident. A short, bearded foreign gentleman approaches and demands access in a German accent, to inspect the scene. Lady Horatia is having none of it and physically blocks his path , firmly instructing a footman to “put him out”, ejecting him from the Hall.  It was in fact Dr August DuPre, the German born Chemist who was Col Majendie’s most important technical assistant and official Home Office consulting chemist who played a key and official role in investigating explosive crime.   PC Cole (later promoted to Sergeant) regained consciousness the next day, and was awarded the Albert Medal for his bravery, which was presented to him on the exact site of the explosion.  Mr Green suffered permanent injury to his sight but was not compensated despite the efforts of the Deputy Sergeant at Arms (probably prompted by the fierce Lady Horatia). Interestingly the body of PC Keith Palmer who was fatally stabbed in 2017 was kept overnight in St Mary Undercroft before his funeral.   My assessment of the device based on an interpretation of the reports and the fact that a James Cunningham was seen lighting a  fuze on a similar bomb that same day at the Tower of London was that the device was a timed IED, with less than 2.5kg of explosives, with burning fuze being the timing element. James Cunningham and an accomplice, Harry Burton, were sentenced to life imprisonment for their role in the bombings. Interestingly this bombing changed the ambivalent feeling of the USA towards the Fenians. Prior to this UK governmental efforts to encourage the US to constrain Fenian activity had fallen on deaf ears, but with an attack on parliament, wheels began to turn.


1939-1945. Although not terrorist attacks, the Houses of Parliament were subject to explosive attack frequently in WW2.   It was hit by German bombs on 12 occasions (nine exploded, 3 were defused) and the House of Commons was destroyed in a subsequent fire after an incendiary bomb attack - one of numerous incendiary bomb attacks.  The buildings were hit three times by our own anti-aircraft guns, one hitting Big Ben. Here’s a Pathe film of the aftermath of one attack.    Particular damage was caused by an explosive bomb on St Stephen’s Cloister on 8 December 1940, and the incendiary attack that destroyed the House of Commons and damaged the roof of Westminster Hall occurred on 10 and 11 May 1941. Three people were killed in all the attacks.

Bomb damage St Stephens Cloister, 1940

1974.  During the construction of the Underground carpark beneath New Palace Yard, the IRA was able to exploit the poor control over a large number of casual workers employed on the contract to place a bomb in a ladies toilet adjacent to Westminster Hall.  It exploded at 8am on 17 June, igniting a gas main causing considerable damage (photo).

1974, Westminster Hall Bombing

The IRA claimed it contained 20 lbs of explosive. That might be an exaggeration.  The device was probably on a  mechanical timer and laid the previous evening, I suspect. The authorities in Westminster have deliberately not removed all the black soot and sign of burning from one corner of Westminster Hall, where is remains to remind those present of the threat to democracy

1979.  The Irish National Liberation Army (INLA) planted a bomb on the car of MP Airey Neave. the device exploded as Neave drove his car out of the underground car park in New Palace Yard. Neave died shortly afterwards. the device probably contained less than 2kg of explosive and was probably initiated by a ball bearing tilt switch. It is possible that the device was placed on the car before it entered Parliament buildings

Neave Assassination

From this list I have excluded a number of nearby incidents, including:

1. A Fenian bombing of the underground between Westminster Bridge station and Charing Cross station in 1882.

2. A suffragette bomb planted in Westminster Abbey in 1914.

3. An IRA mortar attack on Downing Street in 1991.

There are also a number of unsuccessful plots (other than 1605) relating to Westminster which I’m still gathering data on - the strangest is a post WW2 plot to drop bombs contained in adapted fire extinguishers on Parliament by an extreme militant zionist from a charted plane flown from France. More later on that!
Of course the nature of the target of these incidents attracts attention because of the political focus of power from the geography of the target. If I may be allowed a slightly political comment, following the stabbing of PC Keith Palmer and the associated murders on Westminster Bridge some commentators expressed the opinion that London was running scared from terrorism, and that the terrorists were winning. The silly phrase “London has fallen” was used by some of the alt-right to describe the incident, and people talked of Londoners being fearful and terrorised. I don't believe that to be true.  With the possible excerption of the Gunpowder Plot of 1605, none of the other incidents ever caused anyone to suggest that terrorists could defeat our democracy and culture even though they penetrated the buildings of Parliament themselves. In 400 years, attackers have penetrated parliament many times and British culture and democracy remains. The perpertrator of the attack in 2017, armed with his mothers kitchen knife was shot before he entered the building and we can now forget his name.  

Irish Republican Improvised Mortar Design - 1920

In a previous blog post 18 months ago I described how the IRA in 1920 designed and used an improvised mortar.  I’ve now found some context for that development and found out where a damaged mortar tube from 1920 exists today. Some of the below is a repeat of the earlier post and some is new information. 

A number of IRA members had fought in the British Army in WW1 and had experienced trench mortars, either as a user or recipient.   The IRA funded a secret delegation to visit Germany and buy arms on the black market , including a German trench mortar but this mission was unsuccessful.  As a fall-back they asked their engineers to develop a home made mortar based on the British “Stokes” trench mortar.  I’m not sure how closely they followed the design, but the IRA version appears to have been of same calibre as the Mk 1 Stokes mortar (3 inch) and projected an 11lb mortar bomb, again the same as a Mk 1 Stokes mortar.  It appears that the IRA was able to obtain British Army manual for the Stokes mortar.   The tube was made by Matt Furlong’s brother, Joe, at a railway workshop, and Matt (who later died testing a version of the mortar) made the bombs for it at 198 Parnell St, Dublin.               

Some early Stokes mortar bombs are "armed" on launch by use of a grenade lever spring which is released when the lever arm is free to fly off as it leaves the barrel.  I can't be certain but i suspect the 1920 IRA mortar bombs used this principle too, and not the more sophistcated fuze design used in later WW1 Stokes mortars. Here's a British Stokes mortar handbook from 1919 showing the later fuze types. Here's an image of a Stokes mortar with a fuse fitted with a fly off lever.  

The propellant charge was a 12 bore shotgun cartridge with shot removed and more propellant (black powder) added. The impact fuze was adapted from a grenade fuze, (as was the early Stokes mortar bomb fuze). The mortar bomb weighed 11lbs. I donhave exact details but have a pretty good idea and those of you with an EOD background can probably make the same assumptions about arming on launch as I have. For the rest of you, tough.                                                                                                                                                                       
The IRA conducted some extensive trials, under Matt Furlong of this improvised mortar system in October 1920 in County Meath. First a number of dummy mortar bombs with propellant only were fired, to establish ranges and calculate the propellant charge needed for a range of 100 yards.  Then three bombs were fired without a main charge but with an impact fuze fitted to test initiation.   The trials established that the bomb tumbled through the air, but despite that, the fuze appeared to work however it struck the ground.  One of the engineers believed that the impact fuze was being initiated on "set back" within the mortar tube and not on impact at the target. This is an important assessment ignored by Matt Furlong.  Attempts to fire a “live" mortar failed as the bomb got stuck in the tube.  Probably fortunately. 
The engineers involved were concerned about the impact fuze functioning on “set back” within the mortar tube, so they added an additional safety mechanism (which I won’t describe here) and this was was built in to the fuze for subsequent trials. The second set of trials took place near Kells in County Meath.  After firing a live shell with the new safety feature which then failed to function on impact, an argument ensued between Furlong and McHugh, an assistant who was present.  Matt Furlong insisted on removing the additional safety feature and firing the mortar as originally designed. McHugh, nervous, stepped a few yards away.   The others retreated. As the mortar bomb was launched it did indeed explode in the tube, severely injuring Matt Furlong, who later died in hospitalafter losing a limb.
The loss of the mortar was seen as a significant blow to the IRA in Dublin who had expected to be able to mortar barracks with impunity mounting the mortar on the back of a vehicle, a tactic that they applied successfully 60 years later in the North.  

The mortar tube that exploded, eventually killing Matt Furlong, was hidden in the River Tolka for some years before being recovered.In 1937 it was given to the National Museum of Ireland (NMI) were it exists today. Theres some pictures at this link here - it has been mounted at an incorrect angle, but that doesn't matter. 
(Note the damaged base of the mortar tube some way down the page)                                                        
On occasion the arming system also failed in later IRA mortars, as I can vouch for personally. To me there is a clear technological development route from the Stokes mortar of WW1, to the IRA’s improvised Mk 10 and Mk 11 mortars of the late 1980 and early 1990s.  I think there is a distinct posisbility that the PIRA designer of the Mk 10 mortar and bomb based the designs in part on the 1920 Joe Furlong designed mortar and bomb which in itself was based on early WW1 Stokes Mortar designs. 
Additional research leads me to believe that the additional safety feature in the mortar fuze that Matt Furlong removed before his accident was remarkably similar to a fuze safety feature I saw in on operations in 1991 - on another IRA mortar.  That’s seventy years apart, and essentially the same safety feature being used on an improvised mortar.  I won’t post details here, of course. The British Army EOD techs of the time were certainly not aware of that provenance. More fool us.



Rockets, again

This week the police in the Republic of Ireland held a press conference where they displayed a range of weaponry seized from Republican terrorists. Included in the display were rockets which were described as similar to “kassam” rockets used by Palestinian militants in Gaza.  Here’s a picture of one of the rockets.
And here’s some Kassam rockets for comparison
Now of course there is some alarm at this, and understandably so, but regular readers of this blog will know that a recurring theme of mine is that terrorist weaponry, well, has a recurring theme. And this is a great example. One might think from the press coverage that the occurrence of terrorist rockets is new in Ireland, and that these terrorists might have been exchanging technology with Palestinians. I’m not going to comment on that, but let me highlight something - rockets used by revolutionaries in Ireland aren’t new at all. A couple of years back I ran a series of posts about Irish rebel improvised rockets used in Dublin in 1803. That's 216 years ago. And frankly they weren't that dissimilar, a little smaller, but not much so.  And I made the point that the designs used by Emmett’s rebels in Dublin in 1803, were actually built on instructions from an English rocket designer, Robert Anderson, from over a hundred years earlier, in 1696. Here's two pages of those three-hundred-year-old build instructions:
By the way, I still believe that Congreve, who claimed to have invented military rockets in about 1805 was copying Emmet's designs and inadvertently copying the even older design by Robert Anderson.  
Here's the links to the posts about the Dublin rockets of 1803 and their links to the 1696 design.

History lessons

Some earlier posts discussed the home made explosives and IEDs manufactured by Irish republicans shortly after WW1 (around 1920), and I’ve returned to the trove of information I have discovered on this subject. One of the themes of this blog has become the way in which today’s counter-terrorist operatives can learn lessons from the past, and this is a particularly good example.   During the 1980s one of a number of explosive devices designed by the Provisional IRA was a “drogue bomb”.  This basically consisted of a tin full of explosives, with a striker fuze behind it, and it was lobbed at vehicles with plastic strips trailing behind it to ensure it hit the target nose first so activating the striker by momentum.  To the EOD operator this was simple but “new” device.
What is interesting is that it wasn't new at all. In about 1920 the IRA had previously developed what they called then a “drogue bomb”, and the diagram is shown below.  For obvious reasons I’ve left off some of the technical detail - if you are an appropriately accredited EOD operator contact me and I’ll give you the full diagram.   There are of course some differences between this 1920 design and the one from 60 years later in the 1980s… the striker mechanism has switched from the front to the back, and the steel case in the earlier device is thicker.  Those of you knowledgable of other IRA mortars from the 70’s, 80’s and 90’s will also recognise certain aspects of the fusing from this earlier device.  I can tell you that EOD operators of my generation had no knowledge of the history of Irish republican device design from earlier campaigns. More fool us. As I’ve shown in earlier blog posts, improvised munition design used by Irish republicans goes back not only to this post-Easter Rising period, but to much earlier back to almost 1800.   Previous blogs to have highlighted the similarity between an IRA mortar of this 1920 period and the British Stokes Mortar of WW1.


Of course there are similarities to this device and Russian grenades, and I believe also to WW1 German trench grenades which I suspect this device is derived from


Warflour, Paxo and Irish Cheddar

I’ve been doing more research on the IEDs used by the Irish “volunteers” between 1919 and 1922 and found some interesting aspects.   One should remember the time-line of Irish Republicanism that these events of 1919-1922 sit on - Irish revolutionaries were using explosive devices much earlier, certainly as early as 1803, IEDs were used extensively by the Fenians in the latter half of the 19th century, again in 1939 and of course from 1970 onwards.   The window of 1919-122 is just one point on the time line, but is worthy of study for all that.
Firstly, explosives, and I apologise for being somewhat circumspect in the detail here - no need to give modern day revolutionaries with other causes the full recipes. EOD folk can approach me directly of course and I'll point you in the right direction if I know you. At the beginning of the campaign the explosives used was gelignite stolen from quarries, along with “No 6” detonators.  This supply began to become more difficult to obtain and so the Irish volunteers identified chemists and pharmacists and those with military experience from WW1 to develop home made explosives (HME).  There were three types, each given a nickname. I won’t describe their manufacturing process:
“Warflour": Warflour was a nitrated resin, using the ingredients of resin, flour, acid and potassium chlorate.
"Irish Cheddar”:  This was the nickname for a form of cheddite, an explosive used quite extensively in the early 20th century, its ingredients being potassium chlorate, nitrobenzene and castor oil. Some sources suggest that “Cheddar" included home made DNT.  As an aside, this HME was used extensively by the Polish underground in WW2 in their IEDs, which I’ll write about in a future blog post.
"Paxo". This was a mix of potassium chlorate and paraffin wax.  It was the favoured HME in the 1939 campaign but was developed during this period.
The IRA also developed its own detonators at the time, and I won’t describe them here other than to say that interestingly they were non-metallic and quite an effective design.
In terms of IEDs, and further to my earlier post, the IRA of the time made several thousand grenades, mostly under the Dublin Bicycle shop at 198 Parnell St and latterly at other facilities. It appears that the design of these were copied from the German “Egg” grenade of WW1. These were essentially quite a simple design,small and preferred because they were easier to conceal than a larger grenade.  They used the standard sort of fuze with a spring-loaded fly-off lever.  Occasionally larger improvised grenades were used - this is a diagram of one of them, made by an IRA engineer involved in their manufacture. 
IEDs used for roadside ambushes were usually cylindrical pipes, either drain pipes or preferably the cylinders from a  cart axle, filled with gelignite or HME and electrically initiated.  The IRA of the time were ambushing British troops on the roads and certainly learned the trick of laying multiple roadside IEDs at the same spacing as convoy vehicles.  I can find little record of timed IEDs of the time, but the later 1939 “S-Plan” campaign in Great Britain concentrated on the use of timed IEDs.  The cylinders were closed by two end plates - initially with a bolt running down the central axis, and later by a bolt that fitted to the outside of the cylinder.   Command wire initiated devices of this type were occasionally adapated to be come booby traps by the use of a grenade striker system.   The diagram below, drawn by an IRA man shows one such IED.
Further research into the improvised IRA mortar described in my earlier post has thrown up more interesting facts. The background to the IRA requirement was that their roadside campaign was increasingly forcing the police and military to confine themselves to barracks (today we might call them “FOBs”), and the IRA leadership felt they needed a means to attack these barracks directly.  A number of IRA members had fought in the British Army in WW1 and had experienced trench mortars, either as a user or recipient.   The IRA funded a secret delegation to visit Germany and buy arms on the black market , including a German trench mortar but this mission was unsuccessful.  As a fall-back they asked their engineers to develop a home made mortar based on the British “Stokes” trench mortar.  I’m not sure how closely they followed the design, but the IRA version appears to have been of same calibre as the Mk 1 Stokes mortar (3 inch) and projected  an 11lb mortar bomb, again the same as a Mk 1 Stokes mortar.  It appears that the IRA was able to obtain British Army manual for the Stokes mortar.  the tube was made by Matt Furlong’s brother, Joe, at a railway workshop, and Matt (who later died testing a version of the mortar) made the bombs for it at 198 Parnell St.
Additional research leads me to believe that the additional safety feature in the mortar fuze that Matt Furlong removed before his accident was remarkably similar to a fuze safety feature I saw in 1990 or 1991 - on another IRA mortar.  That’s seventy years apart, and essentially the same safety feature being used on an improvised mortar.