[Blog] n-Body Politics

[kreios]

Originally Posted by Air Combat

We’ve looked at space combat, and we’ve looked at how to get people down onto the surface. But how do they fight once on the surface? Specifically, how does air combat look like?

Continue reading...

A very short look into air combat, looking at ground-to-air fire, engine choices, and very fast fighter craft.

[johndallman]

Originally Posted by kreios

A very short look into air combat, looking at ground-to-air fire, engine choices, and very fast fighter craft.

Flying nap-of-earth with a fusion torch at Mach 5 is going to damage anything on the surface that isn't armoured. I'd also worry about detection via the IR from your fusion torch being seen from orbit, reflected back off clouds, and the like.

[kreios]

Originally Posted by johndallman

Flying nap-of-earth with a fusion torch at Mach 5 is going to damage anything on the surface that isn't armoured.

Quite possibly, and I should sit down and actually compute that at some point.

I'd also worry about detection via the IR from your fusion torch being seen from orbit, reflected back off clouds, and the like.

Excellent point. A napkin calculation gives me roughly +11 for jet/stealth hull vs 25 for the fusion torch, both before sensor bonus and range. Accordingly, for a normal SM+10 craft (+9 from sensors), that's a 50/50 detection range of 5 kilometres vs 1,000 kilometres - suggesting that, indeed, my analysis is wrong when considering orbital detection. I'll update the post in the next few days.

[kreios]

I had updated the post a few days ago, adding

Edit As an addition to the original analysis, johndallman over at the gurps forums, pointed out two things: (a) A fusion torch flying close to the ground will do quite a bit of damage to the ground, and (b) it will be easily visible from orbit. I’ll ignore point (a) for now, since the same thing applies to landing shuttles. (b) is quite relevant - the fusion torch fighter will be visible at +25, before sensor bonus and range malus. This is sufficient for a detection range from a 1,000 kilometre orbit for a normal SM+9 spacecraft. Kinetic strikes will follow shortly after.

plus a stealth fighter build.

Additionally: New post!

Originally Posted by Armoured Vehicles

Now that we’ve looked at aerial combat, we’ll follow this up with a short post on vehicle combat - and one that’ll bring us even closer to the limitations of the Spaceships system.

Let’s start by looking at two different vehicles: The tank and the infantry fighting vehicle.

Continue reading...

A short example of two vehicles (IFV, Tank) and infantry weapons capable of hurting them.

[kreios]

Originally Posted by Infantry Combat

Having looked at vehicle combat last time, we’ll now have an example combat on the ground between two parties: One battlesuit-armoured, the other light infantry.

Continue reading...

Example infantry combat, which turns out to not work well even with rules adaptions.

[The_Ryujin]

Can't believe I'm just finding out about your blog (blarg... I've really gotta get out of my slump heh). So far I'm really liking what I'm seeing, keep it up!

Also I've noticed you're having some trouble getting getting Spaceships to line up with what you want and find HEMP a bit to powerful.

Well here are a few posts from my blog I think might help you:

This post hacks the Spaceships system to let you make ships of any size or weight.

A few ways to make vehicles made with the spaceships system more survivable.

This one hacks how Ultra-Tech scales the different warhead options it offers.

And here's my take on how to handle reactive armor in 4th edition to give battlesuits a bit more suitability on the Ultra-Tech battlefield.

I'm also trying to get back to updating my blog and one of the posts I'm working on will cover stronger, military grade armor options for Spaceships that give better and laminated dDR for TL10+ options but at the trade of having higher costs. So hopefully I'll have that one finished soon.


Edit:
Already finished heh

[kreios]

Originally Posted by The_Ryujin

Can't believe I'm just finding out about your blog (blarg... I've really gotta get out of my slump heh). So far I'm really liking what I'm seeing, keep it up!

Thank you.

Also I've noticed you're having some trouble getting getting Spaceships to line up with what you want and find HEMP a bit to powerful.

Indeed, although I have a few posts which are coming closer to that in the backlog.

Well here are a few posts from my blog I think might help you:
*snip*

Thanks! I had already read most of them, but that was quite some time ago. You'll actually find a few similarities in my own posts, for example the structural reinforcement (although my version gives even more HP). In the end, I believe my solution might look a bit different - for HEMP, look for next week's post :-)

[The_Ryujin]

Cool stuff, can't wait to see what you got.

Also, here's my crack at a 70 ton TL10 MBT, note I used my Structural Reinforcement rules for it since I worked on this before your reply and my HR on APEP rounds that brings them more in line with the ammunition modifiers in High-Tech and they only increase cost by 7, not 10 times.

It has 1 110mm main railgun, 2 15mm point defense railguns and the ability to hold a drone that weighs up to 1.2tons. It's driver section has two holographic workstations and a C6 mainframe. At the rear it has two more holographic workstations for the drone operations crew.

It's frontal armor is made of two layers of Diamondoid Laminate sandwiched between three layers of Advanced Nano-Laminate and counts as having double dDR vs shaped charge and plasma attacks. The rest of the tank has conventional Nanocomposite.

Other then this, it follows the basic plan of your 100ton MBT.

TL Vehicle     dST/dHP  Hnd/SR  HT  Move  LWt.  Load  SM  Occ.  dDR    Range  Cost       Loc.  Notes
10 70ton MBT   26/42  -3/5   13   3/30   70   1.6   +5   2+2SV   233/45   504 $12.2M  2C1T2t  [1]
[1]Has dDR 233 on the front vehicle arc that counts as laminated, dDR on the sides, dDR on top, dDR 25 at the rear, and dDR 20 on he bottom.

The 110mm main gun does 7d×8(3) pi++ dDamamge, and has range 17,000/130,000 with APEP or 3d×11 pi++, range 8,600/65,000 with basic ball ammo. The cannon has ROF 1, ST 71M, bulk -13, rcl 3 and holds 133 rounds that weigh 53lbs each.

The two 15mm point defense railguns do 4d+2(2) pi dDamage, and range 100,000/250,000 with APEP or 2d+1(2) pi dDamage, range 50,000/130,000 with basic ball ammo. The guns have ROF 20, ST 49M, bulk -11, rcl 2, and holds 120 rounds per gun that weigh 30lbs each.

Note that the 30lbs per shot for the point defense guns came from running the number with how Spaceships scale things, I personally think that's kinda overkill heh. Also the range figures a semi-fudged. I run some funky numbers to get my EM gun spreadsheet to give me rounds that would weigh as much as what Spaceships lists and the variables effect range. They're probably not too far off though and as you can see, the ranges at a point they almost don't matter in ground combat.

[kreios]

Originally Posted by The_Ryujin

Also, here's my crack at a 70 ton TL10 MBT, note I used my Structural Reinforcement rules for it since I worked on this before your reply and my HR on APEP rounds that brings them more in line with the ammunition modifiers in High-Tech and they only increase cost by 7, not 10 times.

Quite interesting. I did note some things on scale, though:

The 110mm main gun does 7d×8(3) pi++ dDamamge, and has range 17,000/130,000 with APEP or 3d×11 pi++, range 8,600/65,000 with basic ball ammo. The cannon has ROF 1, ST 71M, bulk -13, rcl 3 and holds 133 rounds that weigh 53lbs each.

Is that RoF in Spaceship turns or in seconds?

The two 15mm point defense railguns do 4d+2(2) pi dDamage, and range 100,000/250,000 with APEP or 2d+1(2) pi dDamage, range 50,000/130,000 with basic ball ammo. The guns have ROF 20, ST 49M, bulk -11, rcl 2, and holds 120 rounds per gun that weigh 30lbs each.

The 30lbs seems very high - at my first rough estimate, that's a length/width ratio of almost 150:1 for tungsten.

They're probably not too far off though and as you can see, the ranges at a point they almost don't matter in ground combat.

Agreed; at that point it's either limited by terrain features or shooting tanks in the mountains a hundred kilometres distant.

[The_Ryujin]

Originally Posted by kreios

Quite interesting. I did note some things on scale, though:

Is that RoF in Spaceship turns or in seconds?

Whoops, should of been more clear. Yeah, Spaceships 20sec scale. The tanks full mass would be almost all railgun if it fired at ROF 1 heh.

For some reason the point defense guns are in seconds though. Probably should of waited to get some sleep before stating this up heh.

Originally Posted by kreios

The 30lbs seems very high - at my first rough estimate, that's a length/width ratio of almost 150:1 for tungsten.

Just ran the numbers again and I made a mistake. 30lbs is how much a round would weigh if it was a full sized medium battery, I forgot to reduce the weight for the round for being very rapid fire! It should weigh only 1.5lbs per shot.

If your interested:

Damage in d-scale from railguns is caliber in centimeters×3. This takes into account that railguns have 2 miles/sec of muzzle velocity.

Caliber is 10^((SM+Gb)/13)
SM is the ships size.
Gb is 8 if a major battery, 7 if a medium battery, 6 if a secondary battery, 5 if a tertiary battery and 9 if a spinal battery.

Divide caliber by two if rapid fire, by 4 if very rapid fire.

Bullet weight is 10^((SM+Gw)/4)
SM is the ships size.
Gw is 12 if a major battery, 13 if a medium battery, 14 if a secondary battery, 15 if a tertiary battery and 11 if a spinal battery.

Divide weight by 5 if rapid fire, by 20 if very rapid fire (or by 4 and 16 if you want to be exact, oh David and your pentaphilia).

Number of shots is 10^((SM+Gs)/6)
SM is the ships size.
Gs is 6 if a major battery, 5 if a medium battery, 4 if a secondary battery, 3 if a tertiary battery and 7 if a spinal battery.

Multiply number of shots by 5 if rapid fire or by 20 if very rapid fire (or as before, 4 and 16).

Originally Posted by kreios

Agreed; at that point it's either limited by terrain features or shooting tanks in the mountains a hundred kilometres distant.

Sir, they're counter firing!

Right. How much time until the round reach us?

19 minutes sir!

Very good. Plenty time for tea.