By
Sturgeon
The LORD was with the men of Deseret. They took possession of the hill country, but they were unable to drive the people from the plains, because they had chariots of steel.
—The Book of Latter Day Saints, Ch 8, vs. 3:10, circa 25th Century CE
BULLETIN: ALL INDUSTRIAL-MECHANICAL CONCERNS
SOLICITATION FOR ALL-TERRAIN BATTLE TANK
The Provisional Government of the Lone Free State of Texas and The Great Plains issues the following solicitation for a new All-Terrain Battle Tank. The vehicle will be the main line ground combat asset of the Lone Free State Rangers, and the Texas Free State Patrol, and will replace the ageing G-12 Scout Truck, and fill the role of the cancelled G-42 Scout Truck. The All-Terrain Battle Tank (ATBT) will be required to counter the new Californian and Cascadian vehicles and weapons which our intelligence indicates are being used in the western coast of the continent. Please see the attached sheet for a full list of solicitation requirements.
Submissions will be accepted in USC only.
Supplementary Out of Canon Information:
I. Technology available:
a. Armor:
The following armor materials are in full production and available for use. Use of a non-standard armor material requires permission from a judge.
Structural materials:
i. RHA/CHA
Basic steel armor, 360 BHN. The reference for all weapon penetration figures, good impact properties, fully weldable. Available in thicknesses up to 4 inches (RHA) 8 inches (CHA).
Density- 0.28 lb/in^3.
ii. Aluminum 5083
More expensive to work with than RHA per weight, middling impact properties, low thermal limits. Excellent stiffness.
Fully weldable. Available in thicknesses up to 4 inches.
Mass efficiency vs RHA of 1 vs CE, 0.9 vs KE.
Thickness efficiency vs RHA of 0.33 vs CE, 0.3 vs KE.
Density- 0.1 lb/in^3 (approx. 1/3 of steel).
For structural integrity, the following guidelines are recommended:
For heavy vehicles (30-40 tons), not less than 1 in RHA/1.75 in Aluminum base structure
For medium-light vehicles (<25 tons), not less than 0.5 in RHA/1 in Aluminum base structure
Intermediate values for intermediate vehicles may be chosen as seen fit.
Non-structural passive materials:
iii. HHA
Steel, approximately 500 BHN through-hardened. Approximately 1.5x as effective as RHA against KE and HEAT on a per-weight basis. Not weldable, middling shock properties. Available in thicknesses up to 1 inch.
Density- 0.28 lb/in^3
iv. Fuel
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-0.03 lb/in^3.
v. Assorted stowage/systems
Mass efficiency vs RHA- 1 vs CE, 0.8 vs KE.
vi. Spaced armor
Requires a face of at least 1 inch LOS vs CE, and at least 0.75 caliber LOS vs fullbore AP KE.
Reduces penetration by a factor of 1.1 vs CE or 1.05 vs KE for every 4 inchair gap.
Spaced armor rules only apply after any standoff surplus to the requirements of a reactive cassette.
Reactive armor materials:
vii. ERA
A sandwich of 0.125in/0.125in/0.125in steel-explodium-steel.
Requires mounting brackets of approximately 10-30% cassette weight.
Must be spaced at least 2 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects).
viii. NERA
A sandwich of 0.25in steel/0.25in rubber/0.25in steel.
Requires mounting brackets of approximately 10-30% cassette weight.
Must be spaced at least 1 sandwich thickness away from any other armor elements to allow full functionality. 95% coverage.
The details of how to calculate armor effectiveness will be detailed in Appendix 1.
b. Firepower
i. Bofors 57mm (reference weapon) - 85,000 PSI PMax/70,000 PSI Peak Operating Pressure, high quality steel cases, recoil mechanisms and so on are at an equivalent level to that of the USA in the year 1960.
ii. No APFSDS currently in use, experimental weapons only - Spindle sabots or bourelleted sabots, see for example the Soviet BM-20 100mm APFSDS.
iii. Tungsten is available for tooling but not formable into long rod penetrators. It is available for penetrators up to 6 calibers L:D.
iv. Texan shaped charge technology - 4 CD penetration for high-pressure resistant HEAT, 5 CD for low pressure/ precision formed HEAT.
v. The subsidy-approved GPMG for the Lone Free State of Texas has the same form factor as the M240, but with switchable feed direction.. The standard HMG has the same form factor as the Kord, but with switchable feed direction.
c. Mobility
i. Engines tech level:
1. MB 838 (830 HP)
2. AVDS-1790-5A (908 HP)
3. Kharkov 5TD (600 HP)
4. Detroit Diesel 8V92 (400 HP)
5. Detroit Diesel 6V53 (200 HP)
ii. Power density should be based on the above engines. Dimensions are available online, pay attention to cooling of 1 and 3 (water cooled).
iii. Power output broadly scales with volume, as does weight. Trying to extract more power from the same size may come at the cost of reliability (and in the case of the 5TD, it isn’t all that reliable in the first place).
iv. There is nothing inherently wrong with opposed piston or 2-stroke engines if done right.
d. Electronics
i. LRFs- unavailable
ii. Thermals-unavailable
iii. I^2- Gen 2 maximum
vi. Texas cannot mass produce microprocessors or integrated circuits
vii. Really early transistors only (e.g., transistor radio)
viii. While it is known states exist with more advanced computer technology, the import of such systems are barred by the east coast states who do not approve of their use by militaristic entities.
Armor calculation appendix.
SHEET 1 Armor defeat calculator 4in-54 1200 yd
SHEET 2 Armor defeat calculator 4in-54 2000 yd
SHEET 3 Armor defeat calculator 6in HEAT
Range calculator
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