N-L-M

29 minutes ago, Collimatrix said:

a 100mm air gap,

Checking the model, apparently that's selling the turret a bit short. The turret cheeks are 170 deg thick and set 35 deg off the centerline, topped with a 164mm air gap and then 60mm HH face.

From dead ahead that's 297 RHA-286mm gap- 104mm HH

And from 30 deg off to the side it's 187 RHA-180 gap-66 HH.

The turret sides are 100mm RHA-120mm gap- 30mm HH

and at 30 deg off centerline are 200mm RHA-240mm gap- 60 HH

So the NERA cavities would be 284 mm on the cheek (313mm LOS at +30 deg), and 170mm (340 mm LOS at +30) on the sides.

The turret nose can accommodate some pretty beefy arrays on the production Norman without overly disturbing the driver too-

The production Norman has a slightly rearranged driver's hatch area (for improved visibility), and a slightly rearranged mantlet area (and an actual mantlet, once I get around to modelling the thing):

The upgraded armor of the Norman would have light NERA in the pockets, and heavy ERA (possibly topped with light ERA as well) on the outside.

I may math out just how effective the Cascadian array is at some point, too.

1 hour ago, Collimatrix said:

1)  What are the parameters for gas turbines?

2)  What are the parameters for PELE rounds?  The DM-33 derivative PELE round has 1/3 the penetration of the APFSDS round it's based on.  Does 1/3 penetration seem like a reasonable multiplier for PELE rounds?

The DPRC's jet engine tech is sufficiently advanced to produce P&W JT3D engines and equivalents.

PELE at 1/3 sounds reasonble.

Yes.

It's possible that the Titanium replaces the steel brackets around the NERA and not any individual NERA component. 1100lb is not a lot of weight compared to the almost 10 tons of "special armor" AKA NERA in the tank; if flyer plates were to be replaced with Titanium, then A. That'd be an awful lot of the stuff

B. I'd expect rather significantly larger weight savings, considering just how much of the weight of NERA is steel flyer plates.

While Titanium may have somewhat disappointing ballistic properties, it has excellent mechanical properties, and would be very useful in the mounting bracket application.

Haze Gray has been approved for vehicular camouflage.

Looking good, everyone!

29 minutes ago, Lord_James said:

Also, shouldn’t HHA have a mass efficiency of 2 as it is the same density as RHA

It does.

The mass efficiency numbers given in the OP are the true numbers, the TE numbers are calculated via density.

Praise be unto Her Glorious and Wise Majesty. 

So it is written, so it shall be.

6 minutes ago, Toxn said:

apparently the Californians don't know about it yet...

Scientologists sneer at Cascadian developments!

2 minutes ago, Toxn said:

Elaborate?

The Norman is built of 50mm base RHA with the rest of the base RHA thickness being add-on plate, Stillbrew style; which can then be removed to make way for even more weight of reactive arrays.

I referred to it as "inverse stillbrew" because like stillbrew, it's bolt-on spaced plates intended to improve protection, but it's inverse because the increased protection is achieved by removing them (and using the weight for more efficient armor like NERA).

That's even without applying the truly advanced trickery of the inverse Stillbrew on the Norman.

7 minutes ago, Toxn said:

ie: forget about it

Norman S T R N G

Nope, we're ignoring that.

2 minutes ago, Xoon said:

Does overmatch play a role?

What do you mean?

2 minutes ago, Xoon said:

What about fence/nets? 

Will set of ATGMs and RPGs at the stated standoff.

10 minutes ago, Xoon said:

Does the 50mm spaced armor rule count for artillery fragments, autocannons and small arms? (7,62mm, 12,7mm, 20mm etc.).

10mm for the light threats.

10 minutes ago, Xoon said:

Is the spaced armor rule based on RHAe?

Yes.

10 minutes ago, Xoon said:

Is our glories republic capable for making perforated armor? 

Yes. Counts as the equivalent metal (steel, HH or aluminum) thickness, at a 30% weight discount vs light threats and HEAT. Vs heavy KE threats it has a ME of 1 compared to its base metal, and a TE of 0.7. (And an areal density 0.7 of its base metal of course).

Ribbed armor is considered offensive.

3 minutes ago, Toxn said:

The hull requirements specify 450mm

The mantlet needs some love, being on the turret and all that.

21 hours ago, Toxn said:

35kg

42 minutes ago, Sturgeon said:

105kg

The Oversight Committee for Enforcing Absolute Norms (OCEAN) is interested in knowing how these rounds are to be loaded, both onto the vehicle and into the guns.

9 hours ago, Toxn said:

- 10mm HHA, 30' from vertical

- 5 layers light NERA, 70' from vertical

- 25mm HHA, 30' from vertical

- 60mm RHA base, 30' from vertical

- Areal density: 2731kg/m2

- Thickness: 665mm

I'm getting that the areal density is right, but the LOS thickness is off, unless that is thickness from the normal to the array. For LOS thickness I'm getting 740mm or so.

I'm also getting that this array gets poked by the 500mm KE, but not by the 450mm KE.

18 minutes ago, Toxn said:

I'm not sure if ERA/NERA will work at all on what amounts to a stubby tool-steel telephone pole being thrown at it. So the actual penetration value versus a reactive array might cease to matter. 

Considering the reported effectiveness of Kontakt 5 against M829A1 and A2, which are of broadly similar dimensions and made of DU, with the A3 and A4 likely having sacrificial tips to avoid getting similarly wrecked, I'd say that heavy ERA/NERA will likely work against a steel LR of those dimensions.

On 3/30/2019 at 10:16 PM, LostCosmonaut said:

One of us is making a math error somewhere, here's my array;

 

25mm HHA at 55 deg from vertical

4 layers of light NERA at 67 deg from vertical

76mm RHA at 55 deg from vertical 

 

Total weight is 2740 kg/m2, thickness of 613mm

 

Protects against 500mm KE and 360/960 CE

I'm getting that the precursor, main warhead, and KE threat all poke slightly more than they're supposed to and that the array is defeated by a very small margin in both cases.
Are you using the published K1 equations?
And are you only counting the steel in the NERA towards the LOS feeding component (K2)?

Either of those are minor changes that take the array from "working" to "not".

I'm getting similar density and thickness for the array, so the math there is likely fine.

4 hours ago, DIADES said:

The point I am laboriously making is that the present baseline inflates the mass/volume power density of the AVDS.

The only real difference between the -2 and -5 AVDS was the size of the radiator. Later AVDS versions changed the injection and timing and so on, but the -5 is very close to the -2, to the point where IMO its a no-brainer.

Of course with 20/20 hindsight stuff like RISE would be built in from the start.

1 hour ago, Toxn said:

~650kg/m2 for the hull front

That's approximately 90mm steel LOS equivalent, less than a single NERA-H plate at the stated angle (140mm LOS steel alone), so I strongly suggest you check your math. 

Enemy rounds can be expected to bounce/fail to fuze at approximately 80 degrees from the normal.

CHA and RHA are broadly equal, yes.

Dowrating would solve a lot of the issues, yes.

Opposed pistons have one shaft with a 13-17 deg lead angle to allow good axial scavenging, so they aren't perfectly inherently balanced; at the same time, the individual crankshafts cannot be perfectly balanced in a "straight 5" config, so you have both shafts badly vibrating inside the engine.

Upping the 5TD to 6 cylinders would go a long way to solving some of these problems. And in fact, this is what the Kharkovites did. The 6TD is a more reliable beast (if still not reliable in absolute terms). 

9 hours ago, Toxn said:

Edit: hmmm... thats either very light (and a typo) or remarkably heavy.

What kind of array areal densities are you getting?

Mostly it was overloaded and underbuilt.

It was a very small and light engine, running very fast to achieve the rated power. That combined with Kharkovite QC leads to... interesting things.

Being a 5 cylinder engine and therefore unbalanced and suffering from excessive vibration didn't exactly help either.

10 minutes ago, DIADES said:

3. 8mm coax - anti-personnel

3. 15 mm remote with 8 mm coax = light vehicles and anti-personnel

Kindly replace those with DPRC spec weapons- 7.62x54mmR PKM, 12.7x108mm DShK, or 14.5x114mm KPV.