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Toxn

Competition: A modern medium AFV

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STURGEON'S NOTE: THIS IS JUST FOR FUN, DON'T TAKE IT TOO SERIOUSLY.

 

Toxn's note: what he said. The in-character stuff is just to reflect how these sorts of proposals end up getting bloated all out of proportion as conflicting requirements get tacked on by committees. I'll also try to provide clarity on the requirements themselves as we go along, so ask away.

 

staq1mj.jpg

 

With a slew of regional conflicts threatening to metastasise and military expenditure rising for the first time in decades, military planners are once again pondering the role of AFVs on the modern battlefield. Recent conflicts seem to indicate that armed forces may be faced with lengthy conflicts in urban and peri-urban areas - places where tight confines and large numbers of anti-tank weapons have resulted in attritional warfare. In other areas, more open terrain has favoured the use of man-portable ATGMs against armoured elements. Finally, there has been a long-standing trend towards the use of IEDs and, on the other end of the scale, ever more sophisticated autonomous and semi-autonomous platforms as methods for inflicting casualties upon mechanised and armour forces.

 

These aspects, when combined with a long-standing trend towards more heavily armed and armoured IFV variants, have potentially created a niche for a class of AFV optimised for general combat rather than specific anti-armour or scouting operations. This class of AFV should ideally be air-transportable or air-deployable using existing transport aircraft, be capable of high mobility and survival against infantry-borne weapons, and should be capable of tackling other armed vehicles (up to and including AFVs of a similar configuration) as well as providing infantry support. Other considerations would include the use of the chassis as a basis for a number of specialised variants, the ability to upgrade and retrofit the design during its life cycle and, of course, the cost of the vehicles themselves.

 

As the head of a design team working within a massive defence conglomerate, your task is to come up with a design to pitch to defence departments around the globe. Your basic requirements are as follows:

  • Must be capable of protecting against small arms from all aspects, and must be capable of withstanding 20-30mm autocannon fire across the frontal arc.
  • Must be capable of engaging and defeating existing AFV designs (not including modern MBTs) at modern combat ranges.
  • Must be air-transportable using existing transport aircraft (preferably AC-130 or equivalent) in either a ready-to-run or partially disassembled state.
  • Must be capable of defending against at least one strike by man-portable anti-tank weapons, including ATGMs
  • Must include weaponry or equipment for engaging with dug-in infantry in urban areas
  • Must be capable of defending against mines, roadside bombs and IEDs
  • Must be highly reliable, including servicing at local depots.
  • Must cost the same or less than equivalent systems (around $4 million per unit maximum)
  • Must be capable of off-road travel

Finally, the design must use, wherever possible, existing components and processes in order to minimise development time. As our company specialises in armour arrays (including composites and the like) and electronics, some leeway will be allowed in terms of the armour package and electronic systems. Our extensive contacts within the defence sector mean that any weapon system currently being developed or fielded may plausibly be integrated with our product.

 

Advanced requirements are as follows:

  • May be capable of surviving multiple hits by heavy autocannon (40-60mm) across the frontal arc
  • May be capable of engaging low-flying aircraft and helicopters
  • May be directly air-deployable from existing transport aircraft
  • May be capable of surviving multiple strikes from anti-tank missiles (of all classes) from any angle
  • May include only COTs components
  • May be capable of being serviced in the field.
  • May be in the form of a family of vehicles sharing a common chassis
  • May cost significantly less than equivalent systems (under $3 million per unit)
  • May be capable of extreme off-road travel, including across anti-tank ditches and the like

 

Designs, including at least a picture, description and list of attributes, should be presented by the end of April 2016 for evaluation by a panel of experts. The winning design team will receive a small prize (cash and in-game currency for one of a number of games discussed on this forum) and the adulation of millions of imaginary fans.

 

Good luck!

 

pzdPUvs.jpg

 

IMPORTANT OOC NOTE:

 

The in-character post is sort of supposed to be maddening, as it reflects the tendency to propose a lightweight expeditionary vehicle (the absolute requirements viewed loosely) and then have everyone shove more and more stuff in until it turns into an MBT with an autocannon on top.  The absolute versus optional requirements (some of which simply cannot be reconciled) indicate this.

 

I advise the contestants to look at the trends (including real-life ones that I may not have examined in any detail) and pick their guiding philosophy - bearing in mind that this is supposed to be a vehicle for infantry support and general combat against anything smaller than an MBT. From there you should try to fulfil all of the absolute requirements (some leeway is allowed) and then argue the optional requirements as needed.

 

Above all - have fun!

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Questions and comments:

1. Defending against ATGMs seems to indicate MBT-level protection. Maybe dropping this requirement or allowing loose interpretations of it would be well-advised.

2. "Defend against 20-30mm cannons across the frontal arc; pretty sure I get what you mean by this, but it would be worth clarifying. Are we to defend against 25mm APFSDS, for example, or just 30mm HEDP?

3. "Defend against mines/IEDs", what kind and to what degree? Are we designing an MRAP or a lightweight transportable expeditionary tank? Those are two different requirements sets. If it's up to interpretation, that's fine, but make a note of that. Your post is entirely in-character, and I think generally could use an OOC section where you let us know how rigidly you want the requirements interpreted.

Otherwise, I like it, and will be making a submission. Unless you need me as a judge, that is.

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Reserved for bringing back the Teledyne Expeditionary Vehicle.

 

OK, I have come up with my design.  I'm going to use the hull of the old Teledyne Expeditionary vehicle since it has powertrain commonality with the Bradley family of vehicles and because it was originally designed to fit in a C-130.  Instead of the 105mm overhead gun, I'm going to put the 30mm remote gun station recently developed for the Stryker on this vehicle.  Maybe mount an ATGM on the turret as well if needed.  Cost permitting, I would mount the israeli trophy anti missile system on it to provide active protection against missiles. Modern camera and electronics equipment will help compensate for some of the situational awareness issues that the crew suffered from on the original version of the vehicle.  in a way, it would be a bit of a mini-armata, the two crew in the hull, sitting under the remote turret.  

 

There is no way I am going to get frontal arc protection against 20-30mm cannons on this thing and still be within the weight rules.  Therefore, probably some sort of modular armor that can be flown in separately and later attached will be included to meet this requirement.  

 

All in all, this would make a nice little light tank.  However, there really is nothing it could do that an IFV couldn't, other than be air portable.  

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Here's my starter worksheet for you guys, feel free to work off it:

 

 

 

C-130 cargo hold:
 
length, 40 feet (12.19 m); width, 119 inches (3.02 m); height, 9 
 
feet (2.74 m). Rear ramp: length, 123 inches (3.12 m); width, 
 
119 inches (3.02 m)
 
C-130 maximum payload weight:
 
20.40 tonnes
 
---
 
C-130J cargo hold:
 
length, 55 feet (16.76 m); width, 119 inches (3.02 m); height, 9 
 
feet (2.74 m). Rear ramp: length, 123 inches (3.12 m); width, 
 
119 inches (3.02 m)
 
C-130J maximum payload weight:
 
19.96 tonnes
 
---
 
"Small" goal:
 
8.65 tonnes
 
max 8 meters length, 3 meters width, 2.7 meters height, stowed
 
"Medium" goal:
 
17.3 tonnes
 
max 12 meters length, 3 meters width, 2.7 meters height, stowed

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Questions and comments:

1. Defending against ATGMs seems to indicate MBT-level protection. Maybe dropping this requirement or allowing loose interpretations of it would be well-advised.

 

The absolute requirement is for something like an RPG or second-generation ATGM (ie: no tandem warheads or top attack). The optional requirement is for anything from a vampir to a hellfire. You can, as I mention below, argue some of the 'absolute' requirements away if they simply cannot be reconciled with each other. 

2. "Defend against 20-30mm cannons across the frontal arc; pretty sure I get what you mean by this, but it would be worth clarifying. Are we to defend against 25mm APFSDS, for example, or just 30mm HEDP?

 

20-30mm cannon fire would, in this case, mean AP or HEDP. The optional requirement for 40mm is for the hot stuff, of course. 

3. "Defend against mines/IEDs", what kind and to what degree? Are we designing an MRAP or a lightweight transportable expeditionary tank? Those are two different requirements sets. If it's up to interpretation, that's fine, but make a note of that. Your post is entirely in-character, and I think generally could use an OOC section where you let us know how rigidly you want the requirements interpreted.

 

See below, but the absolute requirement would be for something capable of hitting a mine and keeping the crew alive if nothing else. I personally can't forsee a future conflict where mines and IEDs aren't a big part of the mix one way or the other, but you may have a different opinion.

Otherwise, I like it, and will be making a submission. Unless you need me as a judge, that is.

 

The judges (you know who you are) should note that they can enter the competition - they will just be judged by the rest of the panel and a temporary judge. I will enter a submission strictly as a joke.

 

IMPORTANT OOC NOTE:

 

The in-character post is sort of supposed to be maddening, as it reflects the tendency to propose a lightweight expeditionary vehicle (the absolute requirements) and then have everyone shove more and more stuff in until it turns into an MBT with an autocannon on top.  The absolute versus optional requirements (some of which simply cannot be reconciled) indicate this.

 

I advise the contestants to look at the trends (including real-life ones that I may not have examined in any detail) and pick their guiding philosophy - bearing in mind that this is supposed to be a vehicle for infantry support and general combat against anything smaller than an MBT. From there you should try to fulfil all of the absolute requirements (some leeway is allowed) and then argue the optional requirements as needed.

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Here's my starter worksheet for you guys, feel free to work off it:

 

-random bullshit-

 

 

This, by the way, implies 260 and 520 shp engines for each respective configuration, if you desire 30 hp/tonne (M1A2 Abrams is 24 shp/tonne).

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It also means that if you intend to meet the C-130 portability requirement, you're basically doomed for meeting a lot of the other requirements.

 

If however, your home nation uses Il-76s, you can go up to 60 tonnes because RUSSIA STRONK.

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Also, what transport does it have to fit in? C-130?

C-130 would be ideal, but it is also the grave of a bunch of these sorts of concepts.

 

Argue for another transport if you need to, but also remember that the absolute requirement allows plenty of weasel room for (for instance) shipping the thing without armour packages or in a state that requires some re-assembly before the vehicle is combat-ready.

 

You should, if you stretch things very cleverly, be able to propose something bumping up to the same weight class as a medium tank from WWII.

 

You can also, if you're feeling it, argue that the expeditionary requirements are useless and design something else entirely. Just bear in mind the spirit of the thing and, you know, provide the actual arguments.

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C-130 would be ideal, but it is also the grave of a bunch of these sorts of concepts.

 

Argue for another transport if you need to, but also remember that the absolute requirement allows plenty of weasel room for (for instance) shipping the thing without armour packages or in a state that requires some re-assembly before the vehicle is combat-ready.

 

You should, if you stretch things very cleverly, be able to propose something bumping up to the same weight class as a medium tank from WWII.

 

You can also, if you're feeling it, argue that the expeditionary requirements are useless and design something else entirely. Just bear in mind the spirit of the thing and, you know, provide the actual arguments.

 

OK, thanks. That means the weasel room is deliberately built-in, and I sound like a sperglord wearing a denim skirt and asking the teacher for homework. Gotcha.

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      Armor
      Upper Hull: 76.2 mm / 30 °
      Lower Hull: 76.2 mm / 45 °
      Rear Hull: 38.1 mm / 90 °
      Hull Roof: 25.4 mm
      Hull Floor: 25.4 mm
      Turret Mantlet: 152.4 mm / 90 °
      Turret Front: 152.4 mm / 90 °
      Rear Turret: 90 mm / 90 °
      Turret Roof: 50.8 mm
      Mobility
      Engine: Depends on variant, often AV-1790 w/ CD-850 transmission or Meteor with Merrit-Brown Z.51.R transmission. Variant with Ford GAA and syncromesh transmission also trialled.
      Displacement: Depends on variant
      Gears (F / R): Depends on variant
      Power to weight ratio: Depends on variant
      Top speed: Depends on variant
      Suspension: Depends on variant
      Fuel storage: Depends on variant
      Range: Depends on variant
      Track width: Depends on variant
       
       
    • By LostCosmonaut
      Backstory (skip if you don't like alternate history junk)
       
      The year is 2239. It has been roughly 210 years since the world was engulfed in nuclear war. Following the war, the United States splintered into hundreds of small statelets. While much knowledge was retained in some form (mostly through books and other printed media), the loss of population and destruction of industrial capability set back society immensely.
       
      Though the Pacific Northwest was less badly hit than other areas, the destruction of Seattle and Portland, coupled with the rupturing of the Cascadia Subduction Zone in 2043, caused society to regress to a mid-19th century technology level. However, in the early 2100s, the Cascade Republic formed, centered near Tacoma. The new nation grew rapidly, expanding to encompass most of Washington and Oregon by 2239. The Cascade Republic now extends from the Klamath River in the south to the Fraser River in the north, and from the Pacific roughly to central Idaho. Over time, the standard of living and industrial development improved (initially through salvaging of surviving equipment, by the late 2100s through new development); the population has grown to about 4.5 million (comparable to 1950 levels), and technology is at about a 1940 level. Automobiles are common, aircraft are less common, but not rare by any means. Computers are nonexistent aside from a few experimental devices; while scientists and engineers are aware of the principles behind microchips and other advanced electronics, the facilities to produce such components simply do not exist. Low rate production of early transistors recently restarted.
       
      The current armored force of the Cascade Republic consists of three armored brigades. They are presently equipped with domestically produced light tanks, dating to the 2190s. Weighing roughly 12 tons and armed with a 40mm gun, they represented the apex of the Cascade Republic's industrial capabilities at the time. And when they were built, they were sufficient for duties such as pacifying survivalist enclaves in remote areas. However, since that time, the geopolitical situation has complicated significantly. There are two main opponents the Cascade Republic's military could expect to face in the near future.
       
      The first is California. The state of California was hit particularly hard by the nuclear exchange. However, in 2160, several small polities in the southern part of the state near the ruins of Los Angeles unified. Adopting an ideology not unfamiliar to North Korea, the new state declared itself the successor to the legacy of California, and set about forcibly annexing the rest of the state. It took them less than 50 years to unite the rest of California, and spread into parts of Arizona and northern Mexico. While California's expansion stopped at the Klamath River for now, this is only due to poor supply lines and the desire to engage easier targets. (California's northward advanced did provide the final impetus for the last statelets in south Oregon to unify with the Cascade Republic voluntarily).
       
      California is heavily industrialized, possessing significant air, naval, and armored capabilities. Their technology level is comparable to the Cascade Republic's, but their superior industrial capabilities and population mean that they can produce larger vehicles in greater quantity than other countries. Intelligence shows they have vehicles weighing up to 50 tons with 3 inches of armor, though most of their tanks are much lighter.

      The expected frontlines for an engagement with the Californian military would be the coastal regions in southern Oregon. Advancing up the coastal roads would allow California to capture the most populated and industrialized regions of the Cascade Republic if they advanced far enough north. Fortunately, the terrain near the border is very difficult and favors the defender;


      (near the Californian border)


      The other opponent is Deseret, a Mormon theocratic state centered in Utah, and encompassing much of Nevada, western Colorado, and southern Idaho. Recently, tension has arisen with the Cascade Republic over two main issues. The first is the poorly defined border in Eastern Oregon / Northern Nevada; the old state boundary is virtually meaningless, and though the area is sparsely populated, it does represent a significant land area, with grazing and water resources. The more recent flashpoint is the Cascade Republic's recent annexation of Arco and the area to the east. Deseret historically regarded Idaho as being within its sphere of influence, and maintained several puppet states in the area (the largest being centered in Idaho Falls). They regard the annexation of a signficant (in terms of land area, not population) portion of Idaho as a major intrusion into their rightful territory. That the Cascade Republic has repaired the rail line leading to the old Naval Reactors Facility, and set up a significant military base there only makes the situation worse.
       
      Deseret's military is light and heavily focused on mobile operations. Though they are less heavily mechanized than the Cascade Republic's forces, operating mostly armored cars and cavalry, they still represent a significant threat  to supply and communication lines in the open terrain of eastern Oregon / southern Idaho.


      (a butte in the disputed region of Idaho, near Arco)
       
      Requirements
       
      As the head of a design team in the Cascade Republic military, you have been requested to design a new tank according to one of two specifications (or both if you so desire):
       
      Medium / Heavy Tank Weight: No more than 45 tons Width: No more than 10.8 feet (3.25 meters) Upper glacis / frontal turret armor of at least 3 in (76mm) LoS thickness Side armor at least 1in (25mm) thick (i.e. resistant to HMG fire) Power/weight ratio of at least 10 hp / ton No more than 6 crew members Primary armament capable of utilizing both anti-armor and high explosive rounds Light tank Weight: No more than 25 tons Width: No more than 10.8 feet Upper glacis / frontal turret armor of at least 1 in thickness Side armor of at least 3/8 in (10mm) thickness Power/weight ratio of at least 12 hp / ton No more than 6 crew members Primary armament capable of utilizing both anti-armor and high explosive rounds  
      Other relevant information:
      Any tank should be designed to operate against either of the Cascade Republic's likely opponents (California or Deseret) The primary heavy machine gun is the M2, the primary medium machine gun is the M240. Use of one or both of these as coaxial and/or secondary armament is encouraged. The secret archives of the Cascade Republic are available for your use. Sadly, there are no running prewar armored vehicles, the best are some rusted hulks that have long been stripped of usable equipment. (Lima Tank Plant ate a 500 kt ground burst) Both HEAT and APFSDS rounds are in testing. APCR is the primary anti-armor round of the Cascade Republic. Either diesel or gasoline engines are acceptable, the Cascade Republic is friendly with oil producing regions in Canada (OOC: Engines are at about a late 1940s/early 50s tech level) The adaptability of the tank to other variants (such as SPAA, SPG, recovery vehicle, etc.) is preferred but not the primary metric that will be used to decide on a design. Ease of maintenance in the field is highly important. Any designs produced will be compared against the M4 Sherman and M3 Stuart (for medium/heavy and light tank), as these blueprints are readily available, and these tanks are well within the Cascade Republic's manufacturing capabilities.  
       
       
       
       
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