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Author Topic: Mortars  (Read 2314 times)

Daryk

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Mortars
« on: 04 December 2017, 22:42:48 »
I haven't figured out how to fix ordnance yet, but mortars have been on my mind, so I decided to give them a shot.  The main problem with them (aside from ordnance) is range: real world mortars have ranges measured in kilometers, not meters.  Light (60mm) mortars are effective out to about 3.5km, mediums (81mm in real life, 90mm below for aescetics) to ~6km, and heavies (120mm) ~7km.

The ordnance problem can be mostly chalked up to blast radius and the rules for explosive (type X) damage in ATOW.  Real world blast radii would drive ridiculously high damage values even for the 60mm round (i.e., higher than what I propose below).

Fortunately for the heavy mortar, BA Tube Artillery seems to be an attempt to capture it.  Aside from its range and only being available to BA, I think it does a decent job.

The AP and BD values in the table below represent HE only.  I'm holding off on doing anything else until I figure out a fix for ordnance overall.

Code: [Select]
Weight (kg) Max Min
Analog Bore Weapon AP BD PF Burst DF RF Crew TW Dmg Weapon Reload Range Range
M224 60mm Light 6X 16 1.5 1 72 0.33 2 0.72 20   2 8 maps 3 hexes
M252 90mm Medium 8X 17 2 1 76.5 0.33 3 1.02 40   4 12 maps 3 hexes
M120 120mm Heavy 10X 18 2.5 1 81 0.33 5 3/1 150 15 16 maps 21 hexes

EDIT: I found two things that change my math above.  1) Herb's errata for the conversion formula that rounds the burst factor, and 2) the rules for converting TW area effect damage to AToW (page 213 in AToW). There's a bit of strangeness there due to how they implement the blast attenuation.  It's clearly made for "real" artillery, so it doesn't quite work as written for a 3/1 damage profile, but I've adjusted the above as follows:

Heavy Mortars: Instead of using the page 213 -1AP/-4BD per meter after 15 meters from the target TW hex (with the base damage steady out to that point), I'm going to use -1AP/-1BD per meter as usual for AToW damage (but still starting 15 hexes out from the TW hex).  That means at 60 meters from impact, a heavy mortar would do 3BD (enough to qualify for that 1 point of TW damage in the surrounding TW hexes, I think).  Basically, the damage profile looks like: 10X/18 out to 45 meters from the 1-meter AToW point of impact, then -1AP/-1BD until damage is 0 (at 63 meters from the AToW point of impact).

Medium Mortars: I'm aiming for Medium mortars to do 1 point of TW damage as an AE weapon on the TW hex scale (covering just one hex).  I think the usual -1AP/-1BD figure from the 1-meter impact hex can get there starting from 8X/17.

Light mortars have a bit of a boost beyond ordnance as written to ensure they do damage of some kind out to 14 meters (and be able to inflict one point of damage to an armored target with a near miss; i.e., within 1 meter), but won't be Area Effect at the TW scale.
« Last Edit: 07 January 2018, 10:28:18 by Daryk »

Daemion

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Re: Mortars
« Reply #1 on: 05 December 2017, 02:06:53 »
Would this be RPG scale damage?

And, what kind of issues are you having with ordinance? Access to different munitions with different performances? Ranges and flight times? Scatter and the high failure rate?

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Daryk

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Re: Mortars
« Reply #2 on: 05 December 2017, 05:26:40 »
Yes, these are ATOW scale stats.  The damage values for ordnance aren't exactly consistent with where most of the rest of the weapons in the game, and there's a definite gap between Class E and 'mech scale ammunition.  Ideally, things would be seamless from top to bottom.

boilerman

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Re: Mortars
« Reply #3 on: 06 December 2017, 00:37:59 »
In my opinion the only problem with ATOW mortars, and all ATOW weapons for that matter, is their range brackets. There is not a lot of consistency among weapon types as to what constitutes short, medium, long, and extreme range. I find that annoying.

I like the ordnance class system, it's relatively simple, allows for multiple warhead types and translates to TW just fine; although I imagine someone worked pretty hard to come up with that TW conversion.

I think all your BD values and your heavy mortar AP are far too generous Daryk, but to each their own.
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Daryk

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Re: Mortars
« Reply #4 on: 06 December 2017, 08:39:43 »
Thanks for the feedback, Boilerman!  The Heavy AP comes from converting from the BA Tube Artillery (which has 3/1 TW damage), and all the BD values are based on doing 4 points of damage to an unarmored target at something approaching the kill radius of the real world mortars (ATOW explosive damage is reduced by 1 per meter from the point of impact).  The solution may lie in tying the real world kill radii to Anti-Personnel ordnance.

One of the main issues I have with the ordnance rules is that you're supposed to average the available HE, Anti-Personnel, and Anti-Vehicle damage when converting to TW damage.  I think that's an oversimplification, and that tracking different ammo types isn't too much.

Daryk

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Re: Mortars
« Reply #5 on: 17 December 2017, 17:26:38 »
Made some tweaks based on an errata, and a rule I missed the first time.  Opinions?

Hptm. Streiger

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Re: Mortars
« Reply #6 on: 18 December 2017, 05:10:35 »
I think compared with other weapons the range is to much
I know its more a kind of the "real" stuff, but as a rule of thumb take the given ranges and multiply them with 5-7 and you have "real" ranges.
With those 8 maps the mortars would compete with artillery cannons, otherwise. Of course we are talking about "max" ranges. Your guy might hit some building at this range - but any high agile moving infantry or light armored vehicle will not be there when your rounds arrive. So it make sense to drop the "range" - simple because every vehicle might have some "radar" to warn the surrounding troops of incoming.

about the blast radius... well its the blast radius - I'm pretty sure that modern infantry, maybe even any soldier since the beginning of time, could survive withing that blast radius. "Go prone" take cover, luck.... add body armor and you can take even more.
So the smaller radius is the "effective" kill zone. I think the Corps G3 system had a probability system of hitting a target with spreading ammunition (like pellets, behive or shrapnel) - I need to look, later.

...ok taking all that stuff in account... mortars might really be effective to take out pinned troops - same as the grenade launcher but at longer range and maybe your guy's don't need to be exposed to enemy fire. 
 

Daryk

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Re: Mortars
« Reply #7 on: 18 December 2017, 07:10:42 »
You're absolutely right about diving for cover, and AToW page 213 has a rule for that.

As far as ranges, I lost the file I was working on, but had worked out much increased ranges for regular artillery as well.  Once I recall how I generated those ranges, I'll post them too.

Thanks for the feedback!

 

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