AAA mortars!

Hello all, can anyone tell me if high angle, rapid fire mortars might have any place in the scheme of things in terms of Anti-Aircraft Artillery? What I'm looking for is a short to medium range weapon that can be fired from say 60° to 90°, so very steep to vertical, and lob a large projectile with a small bursting charge that scatters many small bomblets of explosive/fragmentation over a decent area, that detonate a brief time after the bursting charge scatters them apart, and when fired in conjunction with many identical weapons, allows for a vast volume to be filled with fragments, all at once?

Although the thread title says mortars, could rockets work in this role?

EDIT
This was supposed to be a challenge for weapons operational (not planned, not early prototyped, but operational) by mid 1935 thru 1945!

My bad.
 
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It has been tried, it generally hasn't worked out all that well

Japan tried AA mortars, generally had a low ceiling, 600m and lots of duds

UK tried AA rockets, generally too slow to load and the mines had a tendency to drift back to the launcher

Admittedly neither of these are quite what you want, as they rely on contact rather than just a large wide area flak, though the low ceiling and lots of duds will be a problem. However in general the idea has issues, you need a relatively thin walled projectile to do that, which means relatively low velocity. That means a lower ceiling and it takes longer to reach the target area, so you have to predict the course of the target further in advance, meaning more possible volume it could be in
 
This is a horribly impractical and wasteful idea.

At the altitudes it would operate at automatic weapons are much more practical and efficient.
 
This is a horribly impractical and wasteful idea. At the altitudes it would operate at automatic weapons are much more practical and efficient.
Why? And at what altitudes are you talking about? For me, I was thinking about uses aboard ships against dive and torpedo bombers, and on land against strafing/low level attacks against targets like airfields and infrastructure.

Filling the sky with masses of small bomblets, concentrated overhead the ships/runways being attacked, seems like a good last ditch effort weapon, and what automatic weapon is going to have a good range straight up?

Keep in mind, the idea behind this concept is not to hit the target, but rather to fill a known volume with high probability damage/kills.
 
Hello all, can anyone tell me if high angle, rapid fire mortars might have any place in the scheme of things in terms of Anti-Aircraft Artillery? What I'm looking for is a short to medium range weapon that can be fired from say 60° to 90°, so very steep to vertical, and lob a large projectile with a small bursting charge that scatters many small bomblets of explosive/fragmentation over a decent area, that detonate a brief time after the bursting charge scatters them apart, and when fired in conjunction with many identical weapons, allows for a vast volume to be filled with fragments, all at once?

Although the thread title says mortars, could rockets work in this role?

Wthat time frame is in question?
Scattering bomblets over the own territory is a tricky proposal, since it might involve killing your own people and stuff. For the accurate fire, you need good radars, perhaps it is best that we connect radars with actual AA guns via fire control unit as per OTL? Mortars have small muzzle velocity, that results in small ceiling.

If we're talking about modern-day air defense, then I'd suggest a mortar-fired guided AA missile, that will be launched at 300 m/s perhaps, with own rocket motor to speed it up beyond mach 3.
 
Dive bombers pull out at 1000 meters. Torpedo bombers (at least the American ones when the torpedoes finally worked) were offset at least 2000 meters. Out of range in other words.
 
I get the concept but the fact is that you're much more likely to kill something if you directly aim at it with something that shoot projectiles travels in a somewhat straight line and can reach a ceiling higher than 500m. On ships with its limited space its a terrible idea. Its a much worse version of the Pom-Pom vs bofors 40mm debate which showed that more accurate and longer range AAA guns were much more effective than sheer volume of fire. On airfields you stand a better chance of making your own airbase inoperable with UXOs than hitting anything not to mention thats a lot of personel and munitions that could be hitting things with auto cannons instead.

Thing is you can reach the same volumes of fire delivered with conventional AAA only its much deadlier and effective at stopping enemy aircraft.
 
By 35 the mk VIII pom pom, has already been in service for 5 years, what possible advantage could such a weapon hold over that? It has 6-7 times the firing ceiling and effective range with similar volume of fire.

This is a question you have to answer before you can make such a weapon attractive.
 
Well.....the Royal Navy did have the Unrotated Projectile in 1940-41

And the Army had Z-battery AAA Rocket cause of the Bethnal Green disaster

Both while actually entering service were complete failures although the Z-battery did result in the RP-3 rocket which was very successful

For extra 'steam punk cool' they also had this which supposedly did shoot down 2 aircraft!!!!!

A demonstration of the weapon for Churchill on Admiral Jack Tovey's flagship at Scapa Flow dramatically exposed a flaw in the concept. Practice bombs were fired and when there was an unexpected change of wind, they drifted back onto the ship and some became entangled in the rigging and superstructure. The dummy rounds caused little or no damage but Tovey was amused at the embarrassment thus caused to the weapon's advocates, Lindemann and Churchill.[3]

x'D
 
I get the concept but the fact is that you're much more likely to kill something if you directly aim at it with something that shoot projectiles travels in a somewhat straight line and can reach a ceiling higher than 500m. On ships with its limited space its a terrible idea. Its a much worse version of the Pom-Pom vs bofors 40mm debate which showed that more accurate and longer range AAA guns were much more effective than sheer volume of fire. On airfields you stand a better chance of making your own airbase inoperable with UXOs than hitting anything not to mention thats a lot of personel and munitions that could be hitting things with auto cannons instead.

Thing is you can reach the same volumes of fire delivered with conventional AAA only its much deadlier and effective at stopping enemy aircraft.
Although I like your reply and spirit, I have to ask, what weapon did you carry in the army/marines? I was an M60 gunner, and I can say that the farther away/faster a target is moving, the less chance you have of hitting it is going to be. When I took the top gun competition back in the late 1980's, I dropped the longest ranged target with a single round, and the pesky range officer, who was threatening to throw me off the range for using just 2-3 round bursts per target instead of the regulation 6-9 round bursts, when the target dropped, so did his jaw. I had no more problems with him telling me how to be an effective gunner after that. I tell you this because I want to establish my creds, so to speak. As an infantrymen, all our training targets were stationary, and so very easy to hit. Had that 1,000 m target been moving, even a little, one shot would not have been enough.

An aircraft, moving at speeds no automobile of the times could achieve on the roads of the day, is something of an acquired skill, in that shooting at something moving at those speeds is not a skill one can get hunting small/big game, and adding in the three dimensional aspect makes this even harder, and so such skills can only really start accruing to those in the military, using military weapons, and if one is to hit an aircraft target, one really needs to be shooting at an airborne target, and unfortunately, a towed target is not moving in the same manner as an attacking aircraft is going to be. So the answer?

Augment your line of sight weapons with area denial fire, because you don't need to be able to hit the target if you flood the volume of space they have to transit with a barrage of scattering bomblets, from multiple mortars/launchers.

I'm sorry that I once again didn't make the timeframe clear in the OP, but then again I didn't even give the ranges of the desired weapons. For directly overhead, say a range of 1,000 to 5,000 yards for the bursting charge, and the scattering bomblets should scatter from 100 to 300 yards before detonation, and again, this weapon would be used in numbers, say 10 or more, so you have a large number of bomblets detonation within the targeted volume.
 
Dive bombers pull out at 1000 meters. Torpedo bombers (at least the American ones when the torpedoes finally worked) were offset at least 2000 meters. Out of range in other words.
Ok, let's look at these numbers and see what we can come up with.
So, 1000 meters = what, 3,300 feet? That makes direct fire heavy machine guns and light auto cannons very unlikely to score many hits, especially with the angle of attack being so acute. For a scatterpack round, fired vertically, what kind of altitude can we get from such a weapon?

EDIT:Forgot the torpedo bombers profile. Ok, so early war air dropped torpedoes needed to be dropped at low speed and low altitude, right? So any AAA mortar designed, in the 1930's, to make life hard for such aircraft is going to need to be able to put bad things in their way. Later on, when the drop envelope of the more modern torpedoes opens this up some, how effective could such a mortar system be. As an amature hobbyist, I envisioned a vertical/steep firing solution of between 60° and 90°, but would such a range of motion actually get me a good anti torpedo bomber weapons system in the early part of WWII, of would a bigger range in the elevation of such notional AAA mortars be needed?

I'm thinking about watching fireworks displays, how high do they go before detonation? I'm thinking that a military application, designed to damage/destroy enemy aircraft at low altitude, is going to be designed to go much higher, and scatter explosive bomblets over a larger area than a civilian display.

How far could a powerful mortar, of the 1930's era, put a shell into the air? Now ask what an anti-aircraft mortar is going to be capable of being built to do? In order to get a large number of bomblets in a single 'shell', how big must the mortar be? Could we see something like AAA mortars being built in the 24" to 36" size range? How many would a destroyer sized vessel be able to carry? How many such AAA mortars would be required to produce a TOT 'cloud' of submunitions overhead? Would a 24"-36" mortar be able to lob shells as high as I've imagined, or would they be to small?
 
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Ok, let's look at these numbers and see what we can come up with.
So, 1000 meters = what, 3,300 feet? That makes direct fire heavy machine guns and light auto cannons very unlikely to score many hits, especially with the angle of attack being so acute. For a scatterpack round, fired vertically, what kind of altitude can we get from such a weapon? I'm thinking about watching fireworks displays, how high do they go before detonation? I'm thinking that a military application, designed to damage/destroy enemy aircraft at low altitude, is going to be designed to go much higher, and scatter explosive bomblets over a larger area than a civilian display.

How far could a powerful mortar, of the 1930's era, put a shell into the air? Now ask what an anti-aircraft mortar is going to be capable of being built to do? In order to get a large number of bomblets in a single 'shell', how big must the mortar be? Could we see something like AAA mortars being built in the 24" to 36" size range? How many would a destroyer sized vessel be able to carry? How many such AAA mortars would be required to produce a TOT 'cloud' of submunitions overhead? Would a 24"-36" mortar be able to lob shells as high as I've imagined, or would they be to small?
Japanese got 600m height out of an AA Mortar with a muzzle velocity of 80-150m/s, don't have a proper source just MV of the shell, just used MV of standard mortars used to launch it. US 81mm mortars could hit 210m/s, 107mm 250m/s, so I'd say 105mm and higher necessary for 1000m plus, could be wrong and could do it with less. But still expect 105mm plus

Issue with a 24" mortar is the size. There was a 24" mortar deployed in WWII on a self propelled chassis, that was 124 tons. Presumably a naval mount would weigh similar when all was said and done with navalising it and handling recoil. Issue is it weighs as much as a pair of twin 5" DP mounts, and I'd consider the longer range of the twin 5" much more useful. I'd say AA mortar mounts would have to be small enough not to displace a Bofors Twin or larger weapon, if they were to be practical

Mind you I am of the opinion this would probably not work
 
How many such AAA mortars would be required to produce a TOT 'cloud' of submunitions overhead? Would a 24"-36" mortar be able to lob shells as high as I've imagined, or would they be to small?

Although I see your plan, doesn't it leave your target (presumably a relatively large warship or airfield to carry a weapon that big) with a large cloud of small explosive devices falling back down towards it?

Although it's an interesting idea I don't see how it's more effective than 20 - 40mm AA or 4 - 5in DP guns on ships or light AA or even machine guns for airfields/army units in the field?
 
You probably could make it work. When you take Hogmanay, Guy Fawkes Night, it would be mathematically possible to build a rocket to burst in a formation of Heinkel bombers with enough flax to bring four of five down at at time.
The size of said rockets would be enormous, not very accurate and dammed expensive rendering them impracticable.
Then again the British were very good at producing one off’s and spent time and effort on a lot of new things, some of which worked, some of which didn’t. Maybe Barnes Wallis could come up with something.
 
The PAC, 'Parachute and cable Device' as illustrated below was an anti aircraft system using a rocket rather than a mortar to launch a cable with a parachute into the path of an attacking aircraft. It is stated that this device had a maximum effective altitude of 3000ft and was initially developed for ait field defence, In the Battle of Britain several enemy aircraft were claimed to have been brought down by this defice. A version was also used on Merchant ships to disrupt dive bomber attacks.





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IMVHO this device was a better prospect than the Holman projector https://en.wikipedia.org/wiki/Holman_Projector, That was an improvised anti Aircraft weapon using a pneumatic Mortar to launch a small explosive munition into the path of an attacking aircraft. a later version was designed to us boiler steam to launch the projectile.


th
The Holman Projector
th
Mills bomb in a tin! the Holman projectors' munition,
 
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