Category Archives: Articles

War flag of the Imperial Japanese Army

An unusual Japanese AA Weapon

The Quarterly Newsletter of ‘The Ordnance Society‘ has been carrying a series of short four or five page illustrated articles on Imperial Japanese weapons of WWII, at least the more unusual ones. In Numbers 116 and 117 the suicide ‘lunge-mine’ and the incredible 70mm anti-aircraft barrage mortar are featured (I made one of the latter following C.O. Ellis’ brilliant, instructive articles in Airfix Magazine over fifty years ago). The most recent issue deals with a weapon I had never heard of — Japanese cyanide grenades. The series, written by Peter McAllister, is excellent and is set to continue in future issues. As a wargamer I find the content intriguing and valuable – something to be aware of if you field an Imperial army of the period.

The 70mm Anti-Aircraft Barrage Mortar (7cm Uchlaqe Sosoku-Dan)

During the history of warfare many combatants, from all periods, came up with ideas that worked far better in theory than they did in actual reality. The Imperial Japanese Army (IJA) during WWII was no exception. One of the many ideas the weapon designers of Japan came up with was a rather clever type of anti-aircraft mortar. A surprising amount of thought went into this weapon, available in two calibres, 70mm and 8lmm. I will take a look at the far more common example, the 70mm design.

Drawing of the 70mm Anti-Aircraft Barrage Mortar
70mm Anti-Aircraft Barrage Mortar

The IJA had a fairly sophisticated array of anti-aircraft weapons, aiming systems and detection devices. Why they thought, then, that they needed something as strange as an anti-aircraft mortar is, at first glance, a bit of a mystery. However, at closer inspection it can be seen that there was a strange current running through at least some of the IJA’s weapon design process. One only has to look at the hopper fed Type 11 light machine gun or the mass of (mostly unused) accessories that came along with some manufacturing runs of the Type 99 rifle. And let’s not even discuss the unneeded design of the Type 2 paratrooper rifle. Each of the above examples has something in common with the 70mm anti-aircraft mortar. In theory, they were good ideas but in practice were at least an irritant to the user – if not worse. In short, the IJA infantry’s having a light anti-aircraft weapon on hand in all terrain was a good idea but making that weapon a mortar? Not so much.

The 70mm version of the anti-aircraft barrage mortar was made (starting in 1942) at the Number 1 Army arsenal in Tokyo. As this arsenal already made 70mm mortar barrels for more conventional mortars, presumably the same facilities were used for the barrage mortar. The idea was that the mortar would discharge its projectile which, at its maximum ceiling would eject seven smaller projectiles. Connected to small parachutes these would detonate on enemy aircraft flying at low altitude. To be effective mass barrages would be needed but, despite the fairly widespread issue of the weapon, its use in its intended role was rather ad hoc. It seems that improvised platoons were its most common form of deployment. One such platoon in the Philippines had 31 men operating a mere five devices. What such an under-strength unit was supposed to achieve is anyone’s guess.

The mortar had a smoothbore barrel that was 48 inches long. The barrel was connected to a wooden block described in an American intelligence document of December 1943.

‘The base of the 70mm barrage mortar is a wooden block approximately 10 by 12 by 8 inches. Two bolts fasten a small base plate to the block. The wooden block absorbs the shock of firing and prevents the mortar from embedding itself in the ground’

A later American intelligence document, from March 1945 confirms much of what was written in the 1943 document,

‘The Japanese 70mm barrage mortar was first encountered on Attu. It consists of a smoothbore tube, 4 feet long, the steel plate of which is fastened by two bolts to a wooden block…’

The overall length is 75 inches. At the bottom of the wooden block is a long iron spike. The weapon is prepared and pointed toward the enemy aircraft by embedding this iron spike into the earth. Thus it can be seen that aiming was rather crudely done. The previously quoted document from 1943 simply says,

‘the 70mm or 81mm tube had no settings, controls or adjustments.’

This is a simple and, no doubt, cheaply made weapon. To fire the weapon the projectile was simply dropped down the barrel. If the round failed to fire the whole weapon would be slowly lifted up and gently tilted forwards to allow the round to slowly slide out. As for the projectile, it was as inventive as anything else devised during the war. It’s just a pity (at least for the IJA) that this inventiveness failed to find a better outlet. The same American intelligence document from December 1943 has a good description of the ammunition, presumably examples taken at Attu.

‘Ammunition for the 70mm barrage mortar is packed 10 to a box. The shell contains 7 parachute bombs 3 inches long by 11/16ths of an inch in diameter. A steel cylinder encases the whole assembly. The shell is painted black and is 11 9/16ths inches long and 2.34 inches in diameter. The nose is capped with a wooden disk. After the shell is projected from the mortar by the propelling charge in the base, a time train and fixed powder charge cause the projection of the seven smaller bombs borne by rice paper parachutes. At the same time a larger parachute is opened – tilting the main container and thus ensuring the scattering of the seven bombs.

These small bombs are loaded with three pellets of nitrostarch and are detonated in the air by a sensitive pull-igniter fuze with a phosphorus-coated string and delay element. They may also be used as an effective booby trap for any curious or unwary soldier.’

Again, the later American intelligence document from 1945 confirms much of the earlier intelligence document’s observations with one bonus – the 1945 document includes actual American test information.

‘Five rounds have been fired in a test, with the mortar malfunction of the delay train ignition (ed. – sadly, this is not elaborated on). The shells were quite noisy in flight and tumbled considerably, with the smoke of the black powder delay train clearly visible.

The releasing burst occurred in 7 to 8 seconds at altitudes of 1,520 to 1,660 feet and the shell cases hit the ground close to the firing position. All inert components of the round drifted to the ground within 30 seconds and the bombs drifted nearly half a mile, landing at intervals of about 30 yards.’

An example of a projectile for the barrage mortar that came up for sale some years ago (2007) was painted black with two white bands at the forward end and a red band at the other. The inside of the casing bottom still had some coiled fuse in place. The black painted projectile had a number of markings. On one side was a roughly applied area of white paint, almost a smudge, on which, in black, was the Kanji for ‘east’. The other side had a seven stage, top to bottom, series of Kanji symbols. While this is not an exact they, from top to bottom, translate as ‘seven, military measurement, together, launch, to block(?), to protect the fortress and bullet.’ As noted this may not be an exact translation. Other technical data differs from that already given. At least one modern claim says that the explosive component was RDX and the booster was lead azide. Of course, it’s very possible different types of explosive were used at different times.

It seems that the projectiles could also be fired more conventionally from the standard IJA model 11 70mm mortar. Though it is obscure as to what effect that tactic had on the battle field. Very oddly there is at least one eyewitness case of the barrage mortar being mounted in a Japanese bomber for defence against allied fighters.

The rice paper parachutes were around a foot in diameter, perhaps in some cases a bit larger. It is also clear that black powder could be used instead of the more usual ignition sources. As for maximum range, one American report gives the fairly unlikely number of 4,000 feet. Between 1,000 and 2,000 feet was far more realistic.

The blast radius, despite the small charge of the individual bomblets was around a 10 to 20 yards radius.

Stripping the 70mm barrage mortar was easy. First the barrel was unscrewed from the metal base plates, thus separating it from the wooden base block. The firing pin might then be removed from the fitting that holds it to the base plate. Finally the iron spike is removed from the wooden block.

On a last note, a May 1944 American intelligence report is fairly blunt about the weapon’s prospects in battle,

‘Although no instance has ever been reported of our aircraft being damaged with this weapon, it would appear that this weapon might be very effective against low flying aircraft if used in sufficient quantity.’

As previously noted however, these weapons tended to be used in penny packets. The fact that those issued with them sought to find other uses for the projectiles speaks for itself. In short the 70mm (and 81 mm) anti-aircraft barrage mortars must be considered interesting failures. Before those of British heritage become too smug however, a similar British project did catch the eye of Winston Churchill. Thankfully, cooler heads made sure it came to nothing.

Article by Rob Morgan.

The Home Secretary in Attendance at Sidney Street

The Siege of Sidney Street, 3rd January 1911

Terror in the capital – London Street under siege!

Picture the scene: armed terrorists are holed up in a London street tenement block. Police and soldiers have been called upon to break the deadlock. The Home Secretary is in attendance to witness the outcome. Crowds gather on the street corners as cameramen from a major news company record the unfolding events.

Sounds like something you might see on the nightly news today doesn’t it? But this was London 3 January 1911. It was The Siege of Sidney Street, or as some call it, The Battle of Stepney!

The incident that took place on that fateful day can be traced back a little over two weeks earlier, to the night of 16 December 1910. On that night at around 10pm Max Weil, resident of 120 Houndsditch Road, arrived home to find his sister and their housemaid in a state of mild panic and alarm. They could hear sounds coming from the jeweller’s shop next door at 119 and they assumed someone was trying to break in from the rear of the premises. The jewellery shop was owned by Henry Samuel Harris and it was believed the safe inside it may have contained between £20,000 and £30,000.

After calming his sister and the housemaid, Max set off to the local police station at Bishopgate but came upon a Constable Piper doing his rounds. Max told him what he heard so the constable came to investigate. The property in Houndsditch Road backed onto a neighbouring street and they were separated only by a small yard. The gang who were trying to rob the jewellers had rented 9 and 11 Exchange Buildings but they couldn’t rent 10 for some reason (see photograph below).

Scene of the 1910 Houndsditch   robbery and shootings
Scene of the 1910 Houndsditch robbery and shootings

They were living in 11 and using that as a base of operations but it was from 9 where they would gain access to the jeweller’s shop. Constable Piper checked the premises of 118 and 121 Houndsditch Road,from where he could hear the noise. Finding nothing amiss at those premises, he went around the corner to the Exchange Buildings, to investigate further. At approximately11pm he knocked at the door of 11 Exchange Buildings, as this was the only building with a light on. The door was opened by man who spoke little or no English. The police constable immediately became suspicious, so he decided the best course of action was to report in and summon help. Making his way back to Bishopsgate Police Station, Constable Piper saw two other policemen from the adjoining beats, Constables Woodhams and Choat, and he asked them to watch 120 Houndsditch Round and 11 Exchange Buildings, while he went to the nearby Bishopsgate Police Station to report what he had seen and heard.

He returned with three sergeants and another five constables. At approximately 11.30pm, two of the sergeants, Bentley and Bryant, along with Constable Woodhams, approached 11 Exchange Buildings and knocked on the door. Again, the door was opened by a man who spoke little or no English and Sergeant Bentley asked if anyone was working in the premises. The man didn’t seem to understand the question and the immediately subsequent events are unclear. Sergeants Bentley and Bryant, along with Constable Woodhams, somehow gained access to the premises. One version is the door was shut in their face, so they forced entry whilst another suggests that the door was ajar as the man went back inside the premises and they followed him. What is clear though is that shots rang out, and Sergeant Bentley was killed while Sergeant Bryant and Constable Woodhams were seriously injured (both were later invalided out of the Police Force).

At least three men and a woman were observed running out of 11 and the third Sergeant on the scene, Sergeant Tucker, was killed when one of the assailants opened fire again. Constable Choate managed to tackle one of the gang to the ground but he was callously shot in the back and died though not before the robber he had tackled, had himself been shot by his own gang mate.

Returning to their lodgings, the injured robber was left on a bed with a Model 1907 Dreyse pistol under his mattress. Whether this was to incriminate him in the murders of the police officers or to protect himself in case of arrest, we’ll never know, as he died of the wounds he had received. A doctor was called in the early hours of 17 December. Because he had not heard of the incident the night before he believed some cock and bull story about an accidental shooting from a friend. The doctor left, but returned later that day around 11am, to find the patient dead. Eventually the police found out the identity of the corpse — one George Gardstein — and raided the lodging house where he was resident. They apprehended one Sara Trassjonsky in the next room, burning papers and anarchist material. Whilst George Gardstein was an alias the authorities knew him as a Latvian anarchist and had an idea of the people they were now looking for.

Gardstein’s body was taken to a local mortuary where his face was cleaned, his hair brushed, his eyes opened and his photograph taken. The photograph and descriptions of those who had helped Gardstein escape from 11 Exchange Buildings, were distributed on posters in English and Russian asking for information about the robbers and police murderers. Information from a concerned public poured in and the police soon had a list of ‘persons of interest’ that they would like to interview about the robbery and the shootings.
These persons were; Yakov (or Jacob) Peters, Yourka Dubof, Fritz Svaars, Peter Piaktow, William (or Joseph) Sokoloff, Karl Hoffman, (an alias as his real name was Alfred Dzirco), John Rosen, (real name John Zelin), Max Smoller, Sara Trassjonsky, Nina Vassilleva, Luba Milstein (Svaars’ mistress) and Osip Federoff. Most were arrested and tried but two remained at large -Sokoloff and Svaars. Peter Piaktow appears to be a figment of imagination as he was never tracked down or identified as existing.

Photograph of three policemen with shotguns

On the 1 January 1911 the landlord of 100 Sidney Street contacted police to say that the two remaining suspects were lodging at that address along with a woman, Betty Gershon, believed to be Sokoloff’s mistress. The landlord was asked to return the next day, 2 January 1911, to confirm they were still lodging there. He returned and confirmed they were and on the afternoon of the 2 January the police formulated a plan to apprehend the two criminals.

Let Battle Commence!

In the early hours of 3 January 200 police officers (having been mobilized from both the City of London and Metropolitan forces), proceeded to cordon off the area around 100 Sidney Street. Armed officers were placed in 111, directly opposite 100, to keep a watchful eye, as their colleges in the street below began to wake the residents of the houses on the block and to safely evacuate the civilian population. The landlord of 100 woke the ground floor tenants and asked them to fetch Gershon, saying she was needed by her sick husband. She was grabbed by the police as she left the building and taken to the City of London police headquarters. The house was now empty of all residents apart from Svaars and Sokoloff, neither of whom seemed to be aware of the evacuation.

The structure of the building, with its narrow winding stairwell, meant any approach into the dwelling house during the hours of darkness, would be hazardous for the police. The decision was taken to wait until morning before making an attempt to apprehend the criminals. At about 7:30am a policeman knocked on the door. When there was no response, stones were then thrown at the window to wake the men. Svaars and Sokoloff appeared at the window and, realising who was knocking, opened fire at the police. A police sergeant was wounded in the chest and taken to the London Hospital. Some members of the police returned fire but being equipped only with short range shotguns and small calibre revolvers, their guns proved ineffective against the comparatively advanced automatic weapons of Svaars and Sokoloff.

An exchange of fire continued until about 9:00am when it became apparent that the two gunmen possessed superior weapons and ample ammunition for a prolonged siege. The police officers in charge at the scene, a Superintendent Mulvaney and a Chief Superintendent Stark, contacted the Assistant Commissioner, Major Frederick Wodehouse at Scotland Yard and said they would need greater assistance if they were to apprehend the two criminals. Major Wodehouse telephoned the Home Office and asked for, and was granted, permission to bring in a detachment of Scots Guards, who were stationed at the Tower of London. It was the first time that the police had requested military assistance in London to deal with an armed siege. The person who granted the request was none other than Winston Churchill himself. 21 volunteer marksmen from the Scots Guards arrived at about 10:00am and took up positions at each end of the street and in the houses opposite.

The Home Secretary in Attendance at Sidney Street
The Home Secretary in Attendance

Not wishing to miss out on a good photo opportunity, Churchill arrived at the scene about noon. Up until that point sporadic shots from both sides had been made but the tempo then increased for about 30 minutes. At around 1pm smoke was seen coming from the building’s chimneys and from the second floor windows. It was clear that the building had caught fire but no one seems to know how it had started. Also by this time a second detachment of Scots Guards had arrived and they had brought with them a Maxim machine gun (which, in the event was not used). Sokoloff put his head out of a window and he was promptly shot by one of the soldiers. He fell back inside the room but it wasn’t known if he was dead or injured. A senior officer from the London Fire Brigade sought permission to extinguish the blaze but was refused. He approached Churchill in order to have the decision overturned but the Home Secretary approved the police decision to let the building burn, and so ‘flush out’ the terrorists.

Churchill later wrote:

“I now intervened to settle this dispute, at one moment quite heated. I told the fire-brigade officer on my authority as Home Secretary that the house was to be allowed to burn down and that he was to stand by in readiness to prevent the conflagration from spreading”

By 2:30pm, there were no more shots coming from the house. With the upper floors now firmly ablaze a police detective hugging the street walls for safety, approached and pushed the front door open before retreating back again along the street. Armed police officers, along with some of the soldiers, came out onto the street and waited for the men to exit. No one exited the building and part of the roof collapsed due to the fire. It would appear that the men were both dead so the fire brigade was allowed to start extinguishing the blazing building. At 2:40pm, as Churchill was leaving the scene, a detachment from the Royal Horse Artillery arrived with two 13 Pounder field guns. Who had ordered the guns, or even sanctioned their possible use on the city street, was never clarified.

A photograph of 13 pounder field guns in Stepney.
The 13 pounder field guns

When the firemen entered the property to douse the flames they quickly discovered Sokoloff’s body. Due to the intense heat of the blaze and, no doubt, poor construction of the building in the first place, a wall collapsed onto a group of five firemen. They were all taken to the London Hospital and treated for their wounds. One of the firemen involved in the building collapse, Superintendent Charles Pearson, had a fractured spine: He died six months after the siege as a result of his injuries. The firemen shored up the building and made it safe to enter. They resumed their search of the premises and at around 6:30pm a second body was discovered; it was Svaars…and so ended the Battle of Stepney.

Gaming this type of scenario

This type of urban clash/uprising could easily be gamed in the popular scales of 20, 25 and 28mm as there are numerous figures you could either use directly or adapt. In 20mm RH Models has a range of figures suitable for the Scots Guards in their Irish Wars range, whilst some adaptation of figures from Irregular Miniatures’ Very British Civil War range would give you the terrorists. In 25mm the older Airfix range, or possible newer HäT box sets, would give options for soldiers from their WWI British and Artillery boxes but some modification may be need. I’m not sure about 25mm civilians or armed police but maybe the police figures could be made from Colonial British figures with the pith helmet altered to represent a British Bobby’s hat? In 28mm the mass of figures from Reiver Castings in their Very British Civil War range would be idea, but this all depends upon your choice of scale. Buildings could really be any form of three or four storey tenement or shop but you would need a few to make up into the narrow, confined type of street that Sidney Street was. What rules you use, would depend upon personal choice.

I hope this article has give you some ideas to try something different and I hope you have enjoyed reading it.

Article by Grant Parkin.