Competition: Californium 2250

[A. T. Mahan]

1 minute ago, DIADES said:

My experience with AFV interiors is that they are too tight for ease of movement even if one was stark naked and fully greased up..........

 

Your body needs to conform to all the snags, lumps, protrusions and shit, your gear constantly gets caught.  WHEN a vehicle brews up, you need out.  Every gram and every millimeter of cloth/gear is a hindrance.

 

I mean I just want to know if NLM will let me play with my aramids and para-aramids or not

[Donward]

“Bailing out”? 

 

What sort of Wrong Think is this?

 

Armor for our crew minions will increase their devotion to pushing on with the fight!

[A. T. Mahan]

4 minutes ago, Donward said:

“Bailing out”? 

 

What sort of Wrong Think is this?

 

Armor for our crew minions will increase their devotion to pushing on with the fight!

 

That's the spirit! 

 

But seriously, if the TC has turn out for a patrol and gets shot by a Mormon sniper, it'd be nice if they had some more protection than their uniform top and a cigarette case.

[Sturgeon]

17 minutes ago, A. T. Mahan said:

 

That's the spirit! 

 

But seriously, if the TC has turn out for a patrol and gets shot by a Mormon sniper, it'd be nice if they had some more protection than their uniform top and a cigarette case.

 

Yes it's called a hatch and also Activated Thetans.

[DIADES]

47 minutes ago, A. T. Mahan said:

more protection than their uniform top and a cigarette case

Wot!  It were good enough fer grandad....

[N-L-M]

11 hours ago, Collimatrix said:

Are you implying that the Cascadian government would supply Deseret with ATGMs?

The Cascadian Propaganda Service claims any Cascadian weapons in the hands of the Mormonhideen fell of the back of a truck during one of their long range recon patrols into Deseret territory.

 

9 hours ago, Collimatrix said:

light ERA

I should clarify- the k2 rule applies only to the steel LOS in the sandwich. Also I'm not sure how you get to 36mm just from the k2 rule when the sandwich is 3/3/3.

 

There will be a post within the next 24h with a few detail changes to the armor specs and the k1 equations.

9 hours ago, Xoon said:

If a AFV lacks a turret, can it ignore the turret requirements? 

Yes.

9 hours ago, Xoon said:

Does the same apply for a AFV lacking a hull? 

How do you propose to have a vehicle without a hull?

8 hours ago, Lord_James said:

is laminated armor available in DPRC? 

No.

[DIADES]

55 minutes ago, A. T. Mahan said:

 

That's the spirit! 

 

But seriously, if the TC has turn out for a patrol and gets shot by a Mormon sniper, it'd be nice if they had some more protection than their uniform top and a cigarette case.

Crew survivability is only 3rd priority.   Continuing to fight is second so, fight til you die

[N-L-M]

6 hours ago, A. T. Mahan said:

Edit: RIP my math skills, I was wrong.

Low energy, SAD!

 

5 hours ago, A. T. Mahan said:

What is CA’s production capacity for Al2O3, SiC, and aramids?

Not available in the quantities required for AFV protection. Aramid is available in sufficient quantities for select spall lining applications.

 

4 hours ago, A. T. Mahan said:

I just want to give the tank crews fire-protective clothing and body armor.

DPRC armor crews are already outfitted with hypo-allergenic free-range non-GMO organic ergonomic fire retardant clothing and flak vests, which do not count against their weight-lifting ability.

You are however invited to design spall and frag resistant seats and crew stations.

 

I would however remind you that crew survivability is a strictly lower priority than vehicle survivability and continued fightability.

 

1 hour ago, DIADES said:

My experience with AFV interiors is that they are too tight for ease of movement even if one was stark naked and fully greased up..........

Some are better than others but this is pretty accurate.

Though I find that youre actually more maneuverable inside in full protective gear (including helmet), as youre less worried about bashing your head in on sharp corners and the like.

 

Properly designed crew stations and gear have all the annoying sharp corners away from the egress route.

[A. T. Mahan]

@N-L-M Thank you! 

 

For the weight-lifting capability, is this lifting to like shoulder height or above their head?

 

Also, could you clarify:

 

What should we use for the mounting bracket weight for ERA/NERA? 10-30% is a wide variation.

 

And

 

Is there a specification for the steel one might use in a kinetic energy penetrator, specifically in terms of hardness?

[Toxn]

So I've simplified the objective requirements down to the greatest threat normalised to 90 degrees. This should mean that any armour array which can deal with these equivalent threats head-on will be more than capable of dealing with them at their real (offset) angles.

 

Fair warning: don't trust my numbers and use your brain when applying them.

 

Turret front:

• KE: 120mm gun (500mm)
• CE: ATGM (360/960mm)

Turret sides:

• KE: 105mm gun (247mm)
• CE: ATGM (255/679mm)

Turret rear:

• KE: 155mm HE (45mm)
• CE: DPICM (160mm)

Turret/hull roof:

• KE: 155mm HE (45mm)
• CE: ATGM (63/167mm)

Hul front:

• KE: 120mm gun (450mm)
• CE: ATGM (360/960mm)

Hull sides:

• KE: 105mm gun (150mm)
• CE: ATGM (180/480mm)

Hull rear:

• KE: 155mm HE (45mm)
• CE: DPICM (160mm)

Hull floor:

• KE: 3x10kg mines (~50mm)

[holoween]

6 hours ago, Collimatrix said:

 

The 60mm/160mm tandem ATGM has 360mm penetration primary.  Light NERA at 10 degrees is about 3.5 K1 coefficient, so that drops to 102mm penetration.  K2 is 18*1.5/cos(10 degrees), or about 27.4mm, so there is 75mm residual pen after the first light NERA casette.

You just calculated 10° from vertical. So K2 is about 155mm

 

6 hours ago, Collimatrix said:

 

Also, I think you'd get murdered on the above-line-of-sight requirement because the missile would hit the top of the array and bypass the first reactive armor casette entirely.

 

Basic concept looks like this (picture obviously not to scale). So in short the above los is taken care of by the roofprotection.

 

 

[Toxn]

@N-L-M Coli has already mentioned this, but the limitation of 15:1 L/D and no tungsten nerfs the hell out of APFSDS for this competition

[N-L-M]

ADDENDUM 1

Armor details:

1. Fixes.

A. ERA spacing: results from the labs show that ERA need only have 2 sandwich thicknesses away from other elements and not 3 as previously required.

B. Spaced armor: Spaced armor rules apply to the main warhead in a tandem immediately, as the precursor slug counts as a sufficient "face". Base penetration is not however affected.

Light threats (155mm HE frag, SLAP) experience spaced armor effects from 10mm face.

2. Clarifications.

A. In reactives, the K2 factor applies only to the steel LOS in the sandwich. The rubber or explodium do not affect penetration other than by giving the dynamic effect.

B. The spacing between reactive elements is measured normal to the face.

C. To get the ERA/NERA effect, the penetration LOS must enter the front face and exit the back face of the sandwich. Edge and corner hits count only as the steel LOS value.

D. Penetration of light threats:

SLAP-

30mm at 750m

35mm at 500m

40mm at 250m

45mm at 50m

155mm HE-

40mm at 15m

45mm at 10m

50mm at 5m

E. Light threats do not experience dynamic effects of RA (K1 but do experience LOS feeding (K2).

F. The light threats experience spaced armor effects from 10mm LOS steel.

G. The weight of brackets for reactive armor is selectable, where 10% is light and flimsy and 30% is solid.

This affects multi-hit ability in a non-quantified way.

H. The density of rubber and explodium fills of RA is 1.5g/cm^3.

I. Any RA element hit by a precursor takes no part in the action of the main warhead; in passive elements, only the depth not involved in the penetration of the precursor takes part in the action of the primary.

J. DPICM- 40mm HEAT with 4 CD =160mm CE.

3. Additions.

A. Face hardened armor.

Hardened to a depth of 20% or 10mm, whichever is less. Hard face acts like HHA, including making it difficult to attach things to.

B. Equations for K1 curves:

Will be posted soon, check back in 12 hours from the time of posting.

 

Other spec changes.

A. Norman killing ranges reduced to 1.5/2.25/3km with a 50% Phit, where rounds that have a lesser Phit are grouped until they do. (For example, 0.3 Phit has a combined probability of at least one hitting of (1-0.7^2)=0.51, so rounds are counted as half a stowed kill).

B. DPRC APFSDS may be of Maraging steel of up to 400 BHN hardness.

 

Changes may take up to 12 hours to be updated in the OP spec.

[N-L-M]

50 minutes ago, Toxn said:

DPICM

DPICM is a threat to the roof of the hull and turret, not to the rear.

[Toxn]

6 minutes ago, N-L-M said:

DPICM is a threat to the roof of the hull and turret, not to the rear.

I read the requirements as all-around, but that makes sense.

[N-L-M]

9 hours ago, holoween said:

150mm cavity with NERA-light at 14° from horizontal, 30mm RHA, 205mm cavity with NERA-light at 10° from horizontal

Them cavities are too short for good coverage. Phoneposting right now, but those cavities gotta be 223 and 311mm respecitvely based on my math.

(To achieve good overlap such that any LOS will penetrate a sandwich in the front face and out the back face, the overall length of the cavity must be (18/cos(α)*3) for a vertically stacked array like you describe.

Also note that the k2 LOS component does not include the rubber.

[holoween]

 

1 hour ago, N-L-M said:

Them cavities are too short for good coverage. Phoneposting right now, but those cavities gotta be 223 and 311mm respecitvely based on my math.

(To achieve good overlap such that any LOS will penetrate a sandwich in the front face and out the back face, the overall length of the cavity must be (18/cos(α)*3) for a vertically stacked array like you describe.

Also note that the k2 LOS component does not include the rubber.

 

Yea youre right.

though with this change

1 hour ago, N-L-M said:

ADDENDUM 1

I. Any RA element hit by a precursor takes no part in the action of the main warhead; in passive elements, only the depth not involved in the penetration of the precursor takes part in the action of the primary.

 

ill redesign the nera elements anyways since its no longer necessary to have 2 different ones for the precursor and main charge.

[N-L-M]

9 minutes ago, holoween said:

 

ill redesign the nera elements anyways since its no longer necessary to have 2 different ones for the precursor and main charge.

NERA is reactive not passive.

NERA plates holed by the precursor do not stop the primary.

[holoween]

Thanks for the clarifying.

[holoween]

3 hours ago, N-L-M said:

B. Spaced armor: Spaced armor rules apply to the main warhead in a tandem immediately, as the precursor slug counts as a sufficient "face". Base penetration is not however affected. 

 

does that mean the airgap for the main charge is the distance from the first plate triggering the spaced rule to the first plate the main charge encounters?

[N-L-M]

Yes.

[Zadlo]

On 3/23/2019 at 5:39 PM, Collimatrix said:

The DPRC has a roughly 1960s level of manufacturing technology,

 

1. But what year to be precise?

In 1969 we had a technology to create Chobham-like composite armor with ceramic tiles in aluminium honeycomb and STEF as a second layer. DPRC has a technology of aluminium production so they can also produce alumina, mullite or maybe even magnesium alumina spinel (MAS).

2. Can we use metal matrix composites with alumina or granite balls as an armor?

3. Are there any restrictions about using tungsten or tungsten carbide as an armor?

 

[N-L-M]

9 minutes ago, Zadlo said:

But what year to be precise?

1961.

9 minutes ago, Zadlo said:

Can we use metal matrix composites with alumina or granite balls as an armor?

No, ceramic production is fully allocated to other projects.

9 minutes ago, Zadlo said:

Are there any restrictions about using tungsten or tungsten carbide as an armor?

As the 100g limit for ammo suggests, tungsten supplies are limited.

So that's a big no.

[Toxn]

11 minutes ago, Zadlo said:

 

1. But what year to be precise?

In 1969 we had a technology to create Chobham-like composite armor with ceramic tiles in aluminium honeycomb and STEF as a second layer. DPRC has a technology of aluminium production so they can also produce alumina, mullite or maybe even magnesium alumina spinel (MAS).

2. Can we use metal matrix composites with alumina or granite balls as an armor?

3. Are there any restrictions about using tungsten or tungsten carbide as an armor?

 

Hate to break it to you, but Chobham is just good old NERA.

[Zadlo]

6 minutes ago, N-L-M said:

No, ceramic production is fully allocated to other projects.

 

But why? 

On the one hand you allow to use fused silica but on the other hand you can't allow to use granite balls which were first used in armor in mid-50s!

I think the competition is a bit broken.

 

And last but not least:

4. What about using doron in armor? In the previous competition it was available to use.