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February 03, 2004

Small Mortars, Part 1. The Japanese "Knee" Mortar.

Okay, lets face it. If you are an infantryman, life sucks. It sucks because your own guys make fun of you (as long as there is room to run). When they get sloppy they accidentally kill and maim you. The pay ain’t that great, and living under canvas or in muddy holes just isn’t all that much fun. (These are many of the reasons I was an artilleryman, lending dignity to what was otherwise a vulgar brawl). Add to that the crappy food, full of sand, smothered in flies (mmmmm, protein!), and living in filth with nasty, inadequate clothing (while those b*st*rd quartermaster guys lived in requisitioned houses and replaced all their clothes all the time, not to mention running the bath and laundry, and always treated you like you were stealing when you needed to replace something), and amusing yourself by seeing how many rats you could kill with your bayonet while waiting for the bombardment to end, or for those flying a**holes to drop their bombs and bugger out for 3 hots and cot with nightcaps at the club.

Then. THEN there’s that other poor dumb b*st*rd who is just as miserable as you are and he’s trying to kill you in the bargain. On purpose, not just by accident, like your own artillery, tanks, and aircraft are doing. (But ya wanna know the dirty little secret? Except when it's for real, and sometimes even then, good chunks of it is fun. As long as there's no serious blood, on either side).

Anyway, people who try to kill you suck. And ones who are trying to do it on purpose, well, they REALLY suck. And not in that nice “lady of the evening” way, either. These people just really, really suck.

So, first they tried to kill you by stabbing you, hacking you, bashing you.


Like with this Georgian infantry officer’s sword, Saxon battle axe, or Swedish war hammer, all standing in for the thousands of years that most people who sucked were trying to do you in at close range. What’s a feller to do? Sharp pointy things, sharp-edged things, and blunt objects HURT.

So, you try to keep people at a distance right? And kill them before they can get close to you. Initially, you go with that bow and arrow thing. But that’s a lot of work (especially cranking that damn crossbow). So, you keep bribing the guys who make the artillery to spend a little effort figuring out how to make little tiny artillery pieces so you can get some of that ‘kill ‘em at a distance’ action! Of course, those damn officers don’t like that much, preferring instead to give you cheap stuff they are comfortable with (and let’s face it, they aren’t that sure, given the way they treat you, they want you to be able to shoot at things far away, because well, y’know, ya might lose your bearings in a battle and shoot the wrong way, right? All as an accident, of course!

But, over time, the other poor dumb b*st*rd has a leader who wants to win, and so he arms his guys with guns and so you finally get some of that action because while your officers are mean, fat, and stupid, they don’t like losing either.

Even if the damn thing is a little long.

So, over time, people starting giving you things like these to stick in one end or the other of a tube of steel and you start plinking away. So then what happens? People who hide behind things so you can’t kill them suck.

Okay, two can play that game, and you start hiding too. But then it’s pretty hard to kill those guys who suck because they are trying to kill you. So, after a lot of hemming and hawing, people start handing out grenades so that you can toss them behind that palisade, fence, wall, mound of dirt, and get at those b*st*rds who are hiding there, waiting for a chance to pop up and kill you.

So THEN what happens? Someone gives that other guy a grenade, too. And people who throw grenades at you suck because they are loud and disturb your naps while hiding behind things so that people won’t kill you. And they hurt. Worse, they can kill. And people who do that to you, well, they suck. But since they have to expose themselves kinda to do that, people give you rifles, which shoot farther and more accurately than muskets, and then put telescopes on the rifles, so you can shoot that b*st*rd while he’s too far away to toss that grenade thingy at you.

Then the b*st*rds start giving you silly hats to wear. That just adds to the weight, doesn’t it? Like you don’t have enough other crap to carry around. Like this silly piece of kit that’s always in the way – but someone who REALLY REALLY REALLY sucks started tossing things like Phosgene and Chlorine around. That sucks.

Then as it always seems to happen, the other guy gets that stuff too, and you can go back to napping and leaving each other alone – except for that damn artillery. Of course, then you find out that the other guy has ambitious officers and he starts sending people who sneak up on you under the cover of darkness and throw grenades in your trench. And that sucks. So you put out some barbed wire and get creative with booby traps (booby trap pic). And you have those cool things like machine guns now. Except that you find out that Hiram Maxim (who sucks) has been selling them to everybody and their cousin and everybody has ‘em, and lets face it – people who mow you down in waves with machine guns just because you are trying to kill them suck.

Then, THEN! They take the snotty creeps in the Cavalry and put them in tanks. Now that really sucks. But that’s a different post. I only bring that up here to get out of this trap I’m in and end the War to End All Wars and move on to WWII so I can get to the little mortars.

So, here it is, November 12, 1918, millions of people are dead, and northern France and most of Belgium are pretty well candidates for urban removal. Heck, there are parts of France and Belgium in 2003 where people are finding remnants of the war, and farmers and relic hunters are getting injured by not-quite-dud ordnance and even pockets of Lewisite and mustard gas, which are damn persistent agents.

Okay. We all know there isn’t going to any more war, but heck, we’ve still got soldiers, so let’s do some analysis of the last war. And please please please, let’s have it be a war of maneuver, not position and pure attrition. So Basil Liddel-Hart and JFC Fuller put some thought into it, Heinz Guderian and Erwin Rommel put some thought into it, Marshal Tukhachevskii, Charles De Gaulle, and George Patton too.

Thus our poor dumb b*st*rd infantryman found himself schlepping all that stuff across the countryside (unless he was lucky enough to be motorized) but he still had that problem of people who sucked trying to shoot him, stab him, club him, and hide from him behind stuff so that he couldn’t shoot them. Inconsiderate jerks.

One of the problems with grenades is that about the best the average Joe can do is 35 yards or so. And frankly, you like to keep the bad guy farther away than that. And, what the heck, why not have a bigger bang at that end, too? But – too big a round and you start having to haul some pretty hefty stuff around. So, let’s think small. In the 50-60mm range. Small enough that one guy can hump the mortar itself, along with some ammo, and everybody can carry a few rounds in the platoon, and you’ve got yourself a little gizmo that can get that jerk behind the berm.

Today, we’ll look at the Japanese response to this. In later installments, we’ll look at the US versions, both the Airborne and regular (i.e., with a bipod and baseplate) and the Brit version. The Brit version came in two types as well, a long and a short. We’ll have to settle for the long, since I don’t have a short one. Anyone know of a cheap German and Soviet 50mm platoon mortar that needs a new home, drop me a line!

The Japanese mortar is called the Type 89 Leg Mortar. They called it that because when you put it in it's carrying case, you then strapped it to your leg. In a translation error, it became known as the 'Knee' mortar. This was further reinforced when photos were found of Japanese soldiers holding the mortar on their thigh. These were just cheese photos to impress the Geishas back home - as several GIs found out when they broke their leg trying to shoot 'em. The impression is further reinforced because the baseplate is curved.

Here's a pic of the base, along with, from left to right, a mortar round, Type 91 grenade, and a Brit No. 36 Mills bomb for comparison.

This thing weighs about 11 pounds and fires round weighing 20 to 30 ounces. There was provision to add a small launching charge to the bottom of grenades and you could fire them as well. It was decently accurate and ranged out to over 600 meters.

Tech data:
Actual Data:
Barrel Length: 248mm
Overall Length: 608mm
Weight: 4.7kg
Range with Type 89 Grenade: 650m
Range with non-Type 89 Grenade: 190m
Year Introduced: 1929

The mortar was aimed by holding it at a 45 degree angle and using the white line on the barrel, aligning on the target. There is a clinometer for it, and if anyone has one they don't want anymore, let me know! Range was achieved by an adjusting nut that moved a rod up and down the rifled barrel. The deeper in the barrel, the farther the round would go. It was fired by pulling on a leather handle attached to the trigger. The purpose-built rounds had copper rotating bands and low-pressure expansion chambers that would cause the copper to expand and engage the rifling.

Here is a photo of a Japanese soldier firing a Type 89.

So, there you have a look at the Japanese solution to giving the platoon a little mobile firepower under their direct control. Next time we visit this, we'll hit the Brit version. Below is a picture of the Type 89 The other rounds with it are from left to right - French 50mm, US 60mm, and Brit 2 inch (51mm). The Allies went for a bigger bang with their rounds - we'll see what, if any, the trade-offs were.

Remember, troops - the object in combat is to make the OTHER poor dumb b*st*rd die for his country.