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Restricted: for Operating Thetan Eyes Only By order of Her Gracious and Serene Majesty Queen Diane Feinstein the VIII The Dianetic People’s Republic of California Anno Domini 2250

Comrades! The time of your waiting is over! I introduce to you the Sierra Nevada VagonZavod AFV-50 Gun Tank   Frontal Dimensions Frontal Armor Turret Cheek Armor Array (n

Report from Lt. Col. [REDACTED] People's Auditory Forces Directorate of Political-Moral Reliability, Auditory and Political Officer for SNVZ and Military-Industry Liaison Officer for RFP "New Battle T

Attention trans ladies, natal-ladies, and other, equally valid genders

nDUcsxJ.jpg

 

It is I, Her Gracious and Serene Majesty Queen Diane Feinstein the VIII. I want to talk to you today about bisexuality in ammunition. As you all know bisexuality is the worst possible sexual orientation. Even worse than heterosexuality! For being a bisseuxal means you are at best confused and at worse a traitor to LGBTQQIP2SAA people everywhere. You may ask: Why do we then keep the B in the holy acronym? Because for the same reason the Christians--toxic they may be--still regarded Judas as an Apostle. So that we may be reminded of the failures of our former comrades. Anyway when I mean full caliber, I mean full caliber. For I have seen suggested work arounds and they are the bisexuals of ammunition.

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25 minutes ago, N-L-M said:

66% is scary-high. Also why are your side skirts so heavy and what structure is there supporting them?

Well the base armour is 45mm all around (including the hull floor and roof) as mandated, so this thing is going to be chonky no matter what.

66% is too high, though, given that the IS-3 is supposedly the most armour-heavy tank ever and it's fraction is 57%.

 

The side skirts are so heavy because they are soaking 250/750mm CE penetration at 45' and take up 4.2 square metres of armour area each.

 

In terms of support, they are solidly bolted onto the hull sides via a big-ass bracket that runs alon their length and then hang vertically down. Extensions coming out the hull sides then bolt into the inner side of the skirts.

 

Edit: of course, I made a calculation error (I effectively doubled the area of the front plate). The real armour mass is a hair over 40mt, with the all-up mass being around 64mt. This brings the fraction to 62.5%, which isn't great but is getting closer to the ballpark.

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Comrades! The time of your waiting is over! I introduce to you the Sierra Nevada VagonZavod AFV-50 Gun Tank

 

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Frontal Dimensions

Spoiler

uY5WyVw.png

Frontal Armor

Spoiler

OES20Uv.png

Turret Cheek Armor Array (not to scale)

Spoiler

eOT0AII.png

Top/Side

Spoiler

NdkfRdT.png

ezf124P.png

 

Vital Statistics(as pictured):

Weight : 52.6 Metric Tons

Crew: 3 (Commander, Gunner, Driver)

Length (hull/OAL gun forward): 6.9m/9.3m

Width: 3.9m

Height: 2.4m

 

Engine: Twin Turbocharged+Supercharged V-12 Diesel (880kw/1180hp)

16.73kw/tonne / 22.4hp/tonne

>70 kph on road

 

Armament:

125mm L/48 auto-loaded smoothbore, 30 rounds ready

1x PKT 7.62x54mm Coaxial MG, 3000 rounds

1x KPVT 14.5x114mm AAMG, 500 rounds in 50 round belts

 

 

 

 

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2 hours ago, N-L-M said:

How much of that is armor?

Also, does the hull side stop the reference threats?

I also note that the hull does not stop the BGM-1 from the front.

The exact percentage is currently under review, we haven't worked out the ERA package and side skirts

 

The hull side in the depicted prototype does not stop several of the reference threats, however we are working on both a HIC side skirt and a LIC one which should provide the required protection

 

The hull requires ERA to stop BGM-1 from the front, this has not been  modeled as the ERA design is still in development.

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Quick update on my end;

I've nearly completed the hull. Outstanding work to be done:

Model side skirts and armor

Lower front plate armor array

Fuel tank baffles

Model suspension

Reduce frontal armor array thickness

Add APU

Add Power Pack bay spall liner and fuel tanks

 

 

I've completed everything on else on the Hull including;

Powerpack

Armor array design

Front armor array modeled

Crew compartments

Front Fuel tanks

Shock/blast/mine resistance

Spall liner(s)

Etc

 

Currently weighs around 32 tons (again w/o the turret, side skirts, and suspension)

Final weight is projected to be 70-80 tons

Currently makes ~2000hp

 

Feel free to poke around:

https://cad.onshape.com/documents/6c18ded5ae396dbbd35400ca/w/34ef233c7f8a521e805de1bd/e/50e74f8cdc40ef16e27cee40

 

 

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On an equal weight, bending basis, Mg is about 205% the stiffness of steel vs Al which is about 166% the stiffness of steel.  But the Mg fragments burn, whereas the Al fragments dont.

 

Its probable that 1% pb would be added for nuclear radiation scenario, this would actually improve damping propertics and thus the ballistic backing ability of the Mg.  

 

With appropiate design a Mg hull floor would have great blast resistance.  Being that a little curvature would add massive blast resistance.  Given that is 100mm thick anyway.

 

But the main reason, Mg is easy for casting.  1 piece cast hulls are quick and easy, gravity sand casting will do.

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Oops, my light NERA ERA array kinda defeated 360/960 shaped charge.

 

It starts with light NERA at same slant as upper glacis at 8 degrees.

 

Then 2 small rhomboid light ERA at 30 degree.

 

Then a trailing second shot through light NERA at 8 degrees again.

 

 

Starting was just projecting roof line down.

 

Nb this is after some frontal protection against autocannon

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hull armour

Nose 189mm CE, 125mm KE includes bulkhead 1

Fuel tank 120mm CE, 103mm KE includes bulkhead 2

NERA ERA array

Horizontal Nera at 82

Vertical lefthand Era at 60

Vertical righthand ERA at 60

Horizontal NERA at 82 contines

Includes bulkhead 3 

Final armour, ceramic dwell package

193mm CE, 132mm KE

Includes bulkhead 4

 

Each bulkhead is 100mm Structual Cast Magnesium followed by 25mm textolite (as spall liner/fire resistence).   Bulkheads take up 30% of volume but maybe 10% of protection, 20% of weight

 

I have used interface defeat / dwell structures (shock wave attenuator, confinement, buffer/shear support, weak layer, ceramic, base ) twice but left the KE and CE as given for borosilicate.  Against steel, borosilicate glass can provide some dwell protection but doubtful against tungsten etc.   Is mullite an acceptable choice for 1961? its roughly halfway between quartz and alumina and is basically just high quality porcelain.

 

Total array is about 4.5 tonne per m2.  And fits within the 1.75m depth allotted to it (1.68m).

 

No way is turret anywhere as well armoured as hull.  But design is commander and driver in hull, gunner 1 and gunner 2 in turret.

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2 hours ago, Kal said:

hull armour

Nose 189mm CE, 125mm KE includes bulkhead 1

Fuel tank 120mm CE, 103mm KE includes bulkhead 2

NERA ERA array

Horizontal Nera at 82

Vertical lefthand Era at 60

Vertical righthand ERA at 60

Horizontal NERA at 82 contines

Includes bulkhead 3 

Final armour, ceramic dwell package

193mm CE, 132mm KE

Includes bulkhead 4

 

Each bulkhead is 100mm Structual Cast Magnesium followed by 25mm textolite (as spall liner/fire resistence).   Bulkheads take up 30% of volume but maybe 10% of protection, 20% of weight

 

I have used interface defeat / dwell structures (shock wave attenuator, confinement, buffer/shear support, weak layer, ceramic, base ) twice but left the KE and CE as given for borosilicate.  Against steel, borosilicate glass can provide some dwell protection but doubtful against tungsten etc.   Is mullite an acceptable choice for 1961? its roughly halfway between quartz and alumina and is basically just high quality porcelain.

 

Total array is about 4.5 tonne per m2.  And fits within the 1.75m depth allotted to it (1.68m).

 

No way is turret anywhere as well armoured as hull.  But design is commander and driver in hull, gunner 1 and gunner 2 in turret.

 

This is a fascinating idea, but just to be clear, there's nothing in the armor calculation rules about additional protection gained by making the threat go through layers of alternating density.  I spoke with N-L-M about this, and he didn't see a way to include it without making the armor rules too complicated.

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thats fine.  Interface defeat is not that simple to model.

 

Also

My ulterior motive for all the magnesium is that it would be most suitable for a 1970s tank to use for incorporating alumina LIBA (1990s concept) into the stucture of the tank itself. Fused quartz would also be compatible with that manufacture method.  Which couldv'e been used in 1950s or 1960s if anyone had tried.  Can I do that under the rules or is it no go?  Of the 4 bulkheads, 3 are suitable and 1 is not, for cast in situ quartz LIBA.  I would also use it for sides and rear but not the roof or floor.

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Im also treating polycarbonate as selfsupporting diesel.  Is that ok or can you give values for that.  The polycarbonate is mostly just a placeholder for replacement with interface defeat voodoo prior to combat

 

Scrap that, I'll treat all that polycarbonate etc as '

Assorted stowage/systems

 

Mass efficiency vs RHA- 1 vs CE, 0.8 vs KE.'

Edited by Kal
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I just want to confirm.  If i model the fuel cells as a stack of jerry cans between 2 bulkheads.  That when full, it is only 

'Mass efficiency vs RHA of 1.3 vs CE, 1 vs KE.

 

Thickness efficiency vs RHA of 0.14 vs CE, 0.1 vs KE.

 

Density-0.82g/cm^3.'

ie no space multipler effects.

 

 

and when empty, the space effects can be in full force.

'Reduces penetration by a factor of 1.1 vs CE or 1.05 vs KE for every 10 cm air gap.'

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That was my thought with my armor array: 

 

For both: 

front RHA disrupts projectile, followed by air to decompress and allow fragments to separate from main body, then HHA to shatter the projectile, with first group of NERA to catch whatever gets through HHA. 

 

If it survives:

CE; the middle textolite and RHA plate are to slow down the jet so the second group of NERA will perform better  (the geometry to make the NERA plates crosswise oriented is either a huge pain in my ass, or I have to remake my arrays for the 5th time...). 

 

KE; the middle RHA and textolite are to further erode and disrupt the projectile, and the back JPA plate to catch whatever is left. 

 

I’m also looking to use fuel tank geometry as armor (using tubes filled with fuel to do fun things, but I can’t find the study anymore :(). 

 

Anyway, I’ve updated my turret (it looks either like a chubby Merkava 1/2 turret, or a long T-90A turret), with 1100mm LoS from dead ahead, and at planning on Leopard 2 or Merkava 3 style wedge appliqué as upgrade. 

 

 

Haven’t been working on it much though, as I am finishing my final for school, but hopefully I will have something to present before Friday. 

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Quick question:

Minimal structural thickness for a 40 ton vehicle in Alu is 45mm, but can do do something like 25mm Alu + 50mm air + 20mm Alu? 

Imagine using a pipe, instead of a solid metal piece.

 

Would be useful for inserts. 

 

Also done some more work on the chassis:
Lq8kroK.png

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Is the 5TDF version of the 5TD engine available? 

 

Edit: Can we use the Napier Deltic (or similar) for our vehicles? 

 

Also, can I use polyurethane for insulation? Or are we limited to Urea-formaldehyde and asbestos? 

 

Edit 2: 

Ok, so, I know literally nothing about engines except "fuel and air go in, there is big boom, exhaust and heat come out" and during all that, power is generated. Well, in my general "smack-my-face-against-the-wall-and-see-what-happens" experiment style, I went for a 2-stroke, 21 cylinder, Turbosupercharged diesel engine similar in design on the Napier Deltic, with dimensions (for one bank) as follows: 

 

(technology is roughly comparable to the Jumo 205) 

 

980mm height 

257mm depth 

1770mm width

~1.4 mT

 

14x 130mm diameter pistons 

7x 390mm cylinders (195mm stroke) 

36.2L 

~35 kW/L or 1267kW (1700hp) total

 

… but all that's for 1/3 of the intended engine. I'm not looking for a 5100hp behemoth powering my 85 ton tank (however funny that might be), so should I downsize my engine, or is there any other alternatives I can use? Or just use the linear opposed section I have now and screw the delta?

 

This is only for the engine, not the chargers, or the cooling, or transmission and drives. 

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3 hours ago, Lord_James said:

Is the 5TDF version of the 5TD engine available? 

 

Edit: Can we use the Napier Deltic (or similar) for our vehicles? 

 

Also, can I use polyurethane for insulation? Or are we limited to Urea-formaldehyde and asbestos? 

 

Edit 2: 

Ok, so, I know literally nothing about engines except "fuel and air go in, there is big boom, exhaust and heat come out" and during all that, power is generated. Well, in my general "smack-my-face-against-the-wall-and-see-what-happens" experiment style, I went for a 2-stroke, 21 cylinder, Turbosupercharged diesel engine similar in design on the Napier Deltic, with dimensions (for one bank) as follows: 

 

(technology is roughly comparable to the Jumo 205) 

 

980mm height 

257mm depth 

1770mm width

~1.4 mT

 

14x 130mm diameter pistons 

7x 390mm cylinders (195mm stroke) 

36.2L 

~35 kW/L or 1267kW (1700hp) total

 

… but all that's for 1/3 of the intended engine. I'm not looking for a 5100hp behemoth powering my 85 ton tank (however funny that might be), so should I downsize my engine, or is there any other alternatives I can use? Or just use the linear opposed section I have now and screw the delta?

 

This is only for the engine, not the chargers, or the cooling, or transmission and drives. 

I don't really see the advantage to this design. 

What about a Ethanol powered Turbocharged V12?

Nowhere in the rules does it state that it needs to be diesel. And a ethanol engine would blow other engines out of the water when it comes to power density. Also, I would consider ethanol as more progressive and environmentally friendly, fitting for such a glories nation as ours. 

 

Rotary is also possible. 

 

One thing I have been curious about, is if it is possible to make a X opposed piston, were the piston heads have a wedge shape, and four cylinders meet in the center. Though, simply increasing cylinder volume might be more effective. 

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