Jump to content
Sturgeon's House

Recommended Posts

 

electromagnetic-suspension-system-20-638

To summarize, it appears the be similar to hydropuematic suspension, but is claimed to use one fourth of the power (take with a grain of salt). It is also said to have a longer lifespan than the average suspension.

In the case of power shortage or loss of power, the suspension acts as a normal suspension, although probably very poorly.

 

It can be used as a active suspension, and does not appear to take away internal volume. So does this mean that it is directly better than hydropuematic suspension? And as a last note, it can generate electricity through vibration and movement in the suspension. 

 

I like innovating new ideas but, there has the be a mayor drawback with this system.

 

 

Taking a second look at this.  I think what they mean is that an electromagnetic active suspension system would require less energy than an active hydropneumatic one.  That makes sense; electrical motors are more efficient than hydraulic ones.  They're also heavier, so I suspect that would be one of the trade-offs.

 

I don't know that there's been much research done in active suspensions lately though.

 

And yes, you could use the system to generate electricity, but this isn't necessarily a good idea.  The vibration is coming from the movement of the tank, so if you start generating too much electricity with the suspension you're essentially robbing the engine of power.  Regenerative use of vibration energy would be nifty

 

The system as drawn appears to have all the electromagnetic hardware in the suspension struts themselves.  That would raise the unsprung mass, which is not good for ride quality.  I'm sure you could design it differently and sidestep that problem; most other suspensions do.

Share this post


Link to post
Share on other sites

And yes, you could use the system to generate electricity, but this isn't necessarily a good idea.  The vibration is coming from the movement of the tank, so if you start generating too much electricity with the suspension you're essentially robbing the engine of power.  Regenerative use of vibration energy would be nifty

 

Are you saying that the suspension takes away energy from the engine, or are you talking about overcharging the system? 

 

The excess power from the suspension would turn into heat in the batteries and transformers.  This can simply be fixed with a heat sink. 

 

To avoid the suspension robbing power from the engine you simply have them at separate circuits. And in the case low battery power, you can simply prioritize the engine.   

Share this post


Link to post
Share on other sites

When a tank is moving over uneven ground it will tend to start oscillating, how much and what frequency being a function of the suspension's natural frequency and how high the tank's center of gravity is.  The energy for this oscillation comes from the forward speed of the tank.  If you damp out these oscillations, you're robbing energy from the tank.  So tank suspensions with higher damping coefficients have less pitching oscillation, but they have effectively higher rolling resistance.  Walter found an article from some time ago that mentions this effect.  Look on page 4.

 

So, you could damp out oscillations in the tank with an electrical suspension and turn them into electricity, but the energy is ultimately coming from the tank's engine.  So if you're feeding that energy back to the engine, you're just losing energy from conversion losses.  With a suspension that can be actively controlled, it makes more sense to prevent the oscillations from ever happening rather than trying to harvest them.

Share this post


Link to post
Share on other sites

With the introduction of unmanned turrets on MBTs I have been wondering:

 

 

What protection levels do a unmanned turret need?

 

Do we give  them them the same protection as ordinary turrets? Do we just make them Auto cannon proof from the front and from handheld AT weapons?

 

ops, quoted someone xD

Share this post


Link to post
Share on other sites

The consensus so far seems to be that they can get away with pretty minimal levels of protection.  If they were armored to withstand MBT rounds, you wouldn't get sexy slim unmanned turrets like the falcon, given current armor composite thickness efficiencies.

Share this post


Link to post
Share on other sites

All this talk about fuel has got me thinking; If battery technology continues to improve and a purely electric-powered tank were to be designed, how might protection be affected when the tank has to contain numerous battery packs (which may or may not have a flammable electrolyte) rather than fuel tanks? 

Share this post


Link to post
Share on other sites

All this talk about fuel has got me thinking; If battery technology continues to improve and a purely electric-powered tank were to be designed, how might protection be affected when the tank has to contain numerous battery packs (which may or may not have a flammable electrolyte) rather than fuel tanks? 

Batteries would have to be divided into cells that are all parallel coupled. Right now, the only viable battery is lithium battery. They are highly volatile when damaged, and a chain reaction of these could cause mayor damage. They would have to be armored and isolated from the crew. When it comes to protection i highly doubt they would provide much, maybe except some because of the explosion caused by the lithium. 

Share this post


Link to post
Share on other sites

All this talk about fuel has got me thinking; If battery technology continues to improve and a purely electric-powered tank were to be designed, how might protection be affected when the tank has to contain numerous battery packs (which may or may not have a flammable electrolyte) rather than fuel tanks? 

 

The technology would have to improve rather a lot compared to the current state of things.  The very best lithium-ion batteries are still about 1/15 the volumetric energy density of diesel.  Electric motors are about two to three times more efficient than diesel motors, so the actual amount of energy carried on board for the motors could be less.  Electrical motors would also allow simpler transmissions, so that might save some space too.  But even accounting for those savings I would think you would need something like a fourfold increase in the energy density of batteries in order to have something workable for tanks.

 

And at that point I'm not convinced that the chemistry of the cells would be particularly similar to what exists now, so it's hard to make predictions.

Share this post


Link to post
Share on other sites

   Isn't higher efficiency of electric motors and energy density of diesel a main reason why AFV designers are still trying to put diesel engines/electric motors combo in their vehicles insiead of just going full electrical battaries? For me such system is viable future design/tech.

Share this post


Link to post
Share on other sites

   Isn't higher efficiency of electric motors and energy density of diesel a main reason why AFV designers are still trying to put diesel engines/electric motors combo in their vehicles insiead of just going full electrical battaries? For me such system is viable future design/tech.

 

It may be the reason now.  But in the past, the conversion losses from running a diesel engine to turn a generator to make electricity to run an electrical motor that went to the final drives was less efficient than running a diesel engine to a mechanical transmission to the final drives.  It's only been in recent years that generator and electrical motor efficiency has improved enough that using them both in series is comparable to, or maybe even a little better than mechanical and hydromechanical transmissions.

 

Biggest advantage of the electrical transmission is probably the elimination of the mechanical transmission, which as we know has a nasty habit of breaking down in the middle of Ukraine in 1944 during a full-scale retreat.  Electrical transmissions also make more complex steering systems to implement in tracked vehicles.  Purely mechanical systems that deliver constant power to the tracks, have regenerative, multi-radius steering, and neutral steering are... a little complicated:

 

chieftaingearbox_zps0c25340d.jpg

Share this post


Link to post
Share on other sites

It may be the reason now.  But in the past, the conversion losses from running a diesel engine to turn a generator to make electricity to run an electrical motor that went to the final drives was less efficient than running a diesel engine to a mechanical transmission to the final drives.  It's only been in recent years that generator and electrical motor efficiency has improved enough that using them both in series is comparable to, or maybe even a little better than mechanical and hydromechanical transmissions.

 

Biggest advantage of the electrical transmission is probably the elimination of the mechanical transmission, which as we know has a nasty habit of breaking down in the middle of Ukraine in 1944 during a full-scale retreat.  Electrical transmissions also make more complex steering systems to implement in tracked vehicles.  Purely mechanical systems that deliver constant power to the tracks, have regenerative, multi-radius steering, and neutral steering are... a little complicated:

 

chieftaingearbox_zps0c25340d.jpg

Electrical drive systems also make a lot of sense in wheeled death traps, as the inevitable shafts running all over the shop to drive the wheels tend to take up a lot of internal room on the hull.

 

Going wheeled and electric also allows you to potentially run wheels in reverse and thus eliminate some of the complexity of the suspension units by removing the steering system.

 

The major problem with electric drives is, was and ever shall be that they gobble up strategic resources (copper and, lately, rare earth elements), while a conventional drive system just needs steel. So they represent something of a luxury good in a total war situation.

Share this post


Link to post
Share on other sites

With the introduction of unmanned turrets on MBTs I have been wondering:

 

 

What protection levels do a unmanned turret need?

 

Do we give  them them the same protection as ordinary turrets? Do we just make them Auto cannon proof from the front and from handheld AT weapons?

 

ops, quoted someone xD

 

The unmanned turret on the T-14 for example, features light and thin armor capable of withstanding autocannon fire at best, but it does come equipped with an APS.

I can't say the APS design is ideal. It lacks in many cases, but it will provide the necessary protection against a few KEPs. 

 

On the other hand, an unmanned turret in which every component is tightly placed and with thin armor, is more likely to suffer a catastrophic kill than a "normal" tank unless the ammo rack can be completely sealed after reloading. 

And the damage will be more extensive, always resulting in a mission kill. 

 

Overall it's a more survivable and lighter design, but it is vulnerable to counter-APS solutions. Personally I think the T-14 should have had more armor on the turret. After all, an unmanned turret has a lot less surface to protect.

Share this post


Link to post
Share on other sites

Electrical drive systems also make a lot of sense in wheeled death traps, as the inevitable shafts running all over the shop to drive the wheels tend to take up a lot of internal room on the hull.

 

Going wheeled and electric also allows you to potentially run wheels in reverse and thus eliminate some of the complexity of the suspension units by removing the steering system.

 

The major problem with electric drives is, was and ever shall be that they gobble up strategic resources (copper and, lately, rare earth elements), while a conventional drive system just needs steel. So they represent something of a luxury good in a total war situation.

 

 

Another advantage, implied in one of the articles Walter posted a while back, is that electrical and hydraulic transmissions have a lower moment of inertia, which means that they take less time to spin up.  This should give an advantage during initial acceleration.  This would help reduce exposure time while moving to the next bit of cover, and might even be useful in dodging older ATGMs.

Share this post


Link to post
Share on other sites

I have been recently reading about IFV and APC designs and one thing has always confused me:

Why do so many APCs and IFVs have such tall benches for the crew to sit on?

M113_Interior.jpg

P4114672.jpg

Marder_Mannschaftsabteil.JPG

US_Army_53413_Range_Training_in_India_fi

 

While IFVs like the CV90 does not, which saves a ton of space and makes the vehicle much smaller. (Excluding the newer models which have a 140mm raised troop compartment for seats that protect against landmines and IEDs).

 

While it is true that the the CV90 crew compartment is very small, it still can hold 8 soldiers without any problems for long rides. As for crew ergonomics, I spoke with a CV9030NO gunner. He told me the tank was very spacious and they could easily store their belongings and food. He loved it.

 

And another thing i find weird is the large rear ramp. Swedish testing found a double door to be the best option for a quick dismount. Of course with a very thick rear door, a rear ramp would be the best.

 

Personally I have sat in a M113. It was very spacious, but a little short, my head hit the ceiling which made me sit in very uncomfortable pose, I am of average height so this goes for everyone. There was a lot of space behind the seats to store belongings and such on the right side, on the left side there appeared to be a fuel tank, which i found weird.  I did not like the benches at all, simply because they were too tall, if the benches had been shorter or removed I could sit straight with my legs stretched.  As for width, I can't imagine it being more spacious than any other APC. Shoulder to shoulder as always. 

 

And for comparison, here is the CV90 troop compartment: 

1200038149.jpg

IMG_5399.jpgft-editorial-cv90-lease-purchase-2-.jpgHere is a small one with only one person. And yes, I am aware of the bench like seats, but I am unsure if I would qualify them as benches.

Share this post


Link to post
Share on other sites

I'm not terribly sure I understand you completely, but I think I get the gist of it. Anyway, I think the CV90 benches are spring loaded to dampen any sudden movement (due to explosions). This means that the passengers will suffer less from a sudden acceleration, but that also mean they need less room to decelerate. In vehicles with static benches the passenger upward velocity is the same as the vehicle hull upward velocity. Ergo, you need more space to slow down the passengers, since they're not wearing seatbelts or anything.

 

As you might know, this is important because the dangerous bit about IEDs isn't a hull breach or something, but rather the sudden acceleration/deceleration of the crew/passengers.

 

I know for certain that the driver position is dampened, fairly sure about the other two crew positions and I think the passenger comparment has something similar, but I didn't take photos of that when I was inside one.

 

Here's a photo from the driver seat:

2FR5LOQ.jpg

 

The driver's 'seat' (more like hammock) is suspended by those two red bands (there are two at the rear as well). The things the bands connect to should allow for a bit of slip in case of a sudden upwards acceleration.

 

And yes, the CV90 crew positions are fairly spacious, plenty of room to store bottles and boxes. Especially the driver has a fair amount of room behind him.

Here are some more photos of CV90 crew positions: http://sturgeonshouse.ipbhost.com/index.php?/topic/11-stug-iii-thread-and-also-other-german-vehicles-i-guess/?p=72613

(Yes, they're in the German thread, no I don't have the power to move those three posts.)

 

Also note how the commander and gunner have almost the exact same controls. I seriously had to look for clues on what the commander position was. Found it because the network selector for the commander has a few extra buttons and switches compared to the gunner.

Share this post


Link to post
Share on other sites

 

 

Also note how the commander and gunner have almost the exact same controls. I seriously had to look for clues on what the commander position was. Found it because the network selector for the commander has a few extra buttons and switches compared to the gunner.

 

 

There's been a move towards redundant controls at all crew positions in the turret.  In the Merkava IV, IIRC, the loader can locate and service targets if necessary.

Share this post


Link to post
Share on other sites

Not when you find that by the time battle started, roughly half of the ammunition has been discarded and replaced with beer.

 

It would impair the efficiency of that particular tank, sure, but from a combined arms standpoint it would be a major force multiplier.  Especially when you consider how much beer you could cram in an Abrams' bustle.

Share this post


Link to post
Share on other sites

It would impair the efficiency of that particular tank, sure, but from a combined arms standpoint it would be a major force multiplier.  Especially when you consider how much beer you could cram in an Abrams' bustle.

Need a positioned captured?  Drive the beer Abrams into a key position, then let the crunchies know that there is beer to be had if they just go protect that tank...

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Similar Content

    • By N-L-M
      ATTENTION DUELISTS:
      @Toxn
      @LostCosmonaut
      @Lord_James
      @DIADES
      @Datengineerwill
      @Whatismoo
      @Kal
      @Zadlo
      @Xoon
      detailed below is the expected format of the final submission.
      The date is set as Wednesday the 19th of June at 23:59 GMT.
      Again, incomplete designs may be submitted as they are and will be judged as seen fit.
       
      FINAL SUBMISSION:
      Vehicle Designation and name

      [insert 3-projection (front, top, side) and isometric render of vehicle here)



      Table of basic statistics:

      Parameter

      Value

      Mass, combat


       
      Length, combat (transport)


       
      Width, combat (transport)


       
      Height, combat (transport)


       
      Ground Pressure, MMP (nominal)


       
      Estimated Speed


       
      Estimated range


       
      Crew, number (roles)


       
      Main armament, caliber (ammo count ready/stowed)


       
      Secondary armament, caliber (ammo count ready/stowed)


       

       
      Vehicle designer’s notes: explain the thought process behind the design of the vehicle, ideas, and the development process from the designer’s point of view.

      Vehicle feature list:
      Mobility:

      1.     Link to Appendix 1- RFP spreadsheet, colored to reflect achieved performance.

      2.     Engine- type, displacement, rated power, cooling, neat features.

      3.     Transmission- type, arrangement, neat features.

      4.     Fuel- Type, volume available, stowage location, estimated range, neat features.

      5.     Other neat features in the engine bay.

      6.     Suspension- Type, Travel, ground clearance, neat features.

      Survivability:

      1.     Link to Appendix 1 - RFP spreadsheet, colored to reflect achieved performance.

      2.     Link to Appendix 2- armor array details.

      3.     Non-specified survivability features and other neat tricks- low profile, gun depression, instant smoke, cunning internal arrangement, and the like.

      Firepower:

      A.    Weapons:

      1.     Link to Appendix 1- RFP spreadsheet, colored to reflect achieved performance.

      2.     Main Weapon-

      a.      Type

      b.      Caliber

      c.      ammunition types and performance (short)

      d.     Ammo stowage arrangement- numbers ready and total, features.

      e.      FCS- relevant systems, relevant sights for operating the weapon and so on.

      f.      Neat features.

      3.     Secondary weapon- Similar format to primary. Tertiary and further weapons- likewise.

      4.     Link to Appendix 3- Weapon system magic. This is where you explain how all the special tricks related to the armament that aren’t obviously available using Soviet 1961 tech work, and expand to your heart’s content on extimated performance and how these estimates were reached.

      B.    Optics:

      1.     Primary gunsight- type, associated trickery.

      2.     Likewise for any and all other optics systems installed, in no particular order.

      C.    FCS:

      1.     List of component systems, their purpose and the basic system architecture.

      2.     Link to Appendix 3- weapon system magic, if you have long explanations about the workings of the system.

      Fightability:

      1.     List vehicle features which improve its fightability and useability.

      Additonal Features:

      Feel free to list more features as you see fit, in more categories.

      Free expression zone: Let out your inner Thetan to fully impress the world with the fruit of your labor. Kindly spoiler this section if it’s very long.


       Example for filling in Appendix 1
    • By N-L-M
      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

      SUBJ: RFP for new battle tank

      1.      Background.
      As part of the War of 2248 against the Perfidious Cascadians, great deficiencies were discovered in the Heavy tank DF-1. As detailed in report [REDACTED], the DF-1 was quite simply no match for the advanced weaponry developed in secret by the Cascadian entity. Likewise, the DF-1 has fared poorly in the fighting against the heretical Mormonhideen, who have developed many improvised weapons capable of defeating the armor on this vehicle, as detailed in report [REDACTED]. The Extended War on the Eastern Front has stalled for want of sufficient survivable firepower to push back the Mormon menace beyond the Colorado River south of the Vegas Crater.
      The design team responsible for the abject failure that was the DF-1 have been liquidated, which however has not solved the deficiencies of the existing vehicle in service. Therefore, a new vehicle is required, to meet the requirements of the People’s Auditory Forces to keep the dream of our lord and prophet alive.


       
      Over the past decade, the following threats have presented themselves:

      A.      The Cascadian M-2239 “Norman” MBT and M-8 light tank

      Despite being approximately the same size, these 2 vehicles seem to share no common components, not even the primary armament! Curiously, it appears that the lone 120mm SPG specimen recovered shares design features with the M-8, despite being made out of steel and not aluminum like the light tank. (based on captured specimens from the battle of Crater Lake, detailed in report [REDACTED]).
      Both tanks are armed with high velocity guns.

      B.      The Cascadian BGM-1A/1B/1C/1D ATGM

      Fitted on a limited number of tank destroyers, several attack helicopters, and (to an extent) man-portable, this missile system is the primary Cascadian anti-armor weapon other than their armored forces. Intelligence suggests that a SACLOS version (BGM-1C) is in LRIP, with rumors of a beam-riding version (BGM-1D) being developed.

      Both warheads penetrate approximately 6 cone diameters.

      C.      Deseret tandem ATR-4 series
      Inspired by the Soviet 60/105mm tandem warhead system from the late 80s, the Mormon nation has manufactured a family of 2”/4” tandem HEAT warheads, launched from expendable short-range tube launchers, dedicated AT RRs, and even used as the payload of the JS-1 MCLOS vehicle/man-portable ATGM.
      Both warheads penetrate approximately 5 cone diameters.

      D.      Cascadian HEDP 90mm rocket
      While not a particularly impressive AT weapon, being of only middling diameter and a single shaped charge, the sheer proliferation of this device has rendered it a major threat to tanks, as well as lighter vehicles. This weapon is available in large numbers in Cascadian infantry squads as “pocket artillery”, and there are reports of captured stocks being used by the Mormonhideen.
      Warhead penetrates approximately 4 cone diameters.

      E.      Deseret 40mm AC/ Cascadian 35mm AC
      These autocannon share broadly similar AP performance, and are considered a likely threat for the foreseeable future, on Deseret armored cars, Cascadian tank destroyers, and likely also future IFVs.

      F.      IEDs

      In light of the known resistance of tanks to standard 10kg anti-tank mines, both the Perfidious Cascadians and the Mormonhideen have taken to burying larger anti-tank A2AD weaponry. The Cascadians have doubled up some mines, and the Mormons have regularly buried AT mines 3, 4, and even 5 deep.

      2.      General guidelines:

      A.      Solicitation outline:
      In light of the differing requirements for the 2 theaters of war in which the new vehicle is expected to operate, proposals in the form of a field-replaceable A-kit/B-kit solution will be accepted.

      B.      Requirements definitions:
      The requirements in each field are given in 3 levels- Threshold, Objective, and Ideal.
      Threshold is the minimum requirement to be met; failure to reach this standard may greatly disadvantage any proposal.

      Objective is the threshold to be aspired to; it reflects the desires of the People’s Auditory Forces Armored Branch, which would prefer to see all of them met. At least 70% must be met, with bonus points for any more beyond that.

      Ideal specifications are the maximum of which the armored forces dare not even dream. Bonus points will be given to any design meeting or exceeding these specifications.

      C.      All proposals must accommodate the average 1.7m high Californian recruit.

      D.      The order of priorities for the DPRC is as follows:

      a.      Vehicle recoverability.

      b.      Continued fightability.

      c.       Crew survival.

      E.      Permissible weights:

      a.      No individual field-level removable or installable component may exceed 5 tons.

      b.      Despite the best efforts of the Agriculture Command, Californian recruits cannot be expected to lift weights in excess of 25 kg at any time.

      c.       Total vehicle weight must remain within MLC 120 all-up for transport.

      F.      Overall dimensions:

      a.      Length- essentially unrestricted.

      b.      Width- 4m transport width.

                                                                    i.     No more than 4 components requiring a crane may be removed to meet this requirement.

                                                                   ii.     Any removed components must be stowable on top of the vehicle.

      c.       Height- The vehicle must not exceed 3.5m in height overall.

      G.     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 SEA ORG judge.
      Structural materials:

                                                                    i.     RHA/CHA

      Basic steel armor, 250 BHN. The reference for all weapon penetration figures, good impact properties, fully weldable. Available in thicknesses up to 150mm (RHA) or 300mm (CHA).
      Density- 7.8 g/cm^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 100mm.
      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- 2.7 g/cm^3 (approx. 1/3 of steel).

      For structural integrity, the following guidelines are recommended:

      For light vehicles (less than 40 tons), not less than 25mm RHA/45mm Aluminum base structure

      For heavy vehicles (70 tons and above), not less than 45mm RHA/80mm 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 twice as effective as RHA against KE and HEAT on a per-weight basis. Not weldable, middling shock properties. Available in thicknesses up to 25mm.
      Density- 7.8g/cm^3.

                                                                  iv.     Glass textolite

      Mass efficiency vs RHA of 2.2 vs CE, 1.64 vs KE.

      Thickness efficiency vs RHA of 0.52 vs CE, 0.39 vs KE.
      Density- 1.85 g/cm^3 (approximately ¼ of steel).
      Non-structural.

                                                                   v.     Fused silica

      Mass efficiency vs RHA of 3.5 vs CE, 1 vs KE.

      Thickness efficiency vs RHA of 1 vs CE, 0.28 vs KE.
      Density-2.2g/cm^3 (approximately 1/3.5 of steel).
      Non-structural, requires confinement (being in a metal box) to work.

                                                                  vi.     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-0.82g/cm^3.

                                                                vii.     Assorted stowage/systems

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

                                                               viii.     Spaced armor

      Requires a face of at least 25mm LOS vs CE, and at least 50mm LOS vs KE.

      Reduces penetration by a factor of 1.1 vs CE or 1.05 vs KE for every 10 cm air gap.
      Spaced armor rules only apply after any standoff surplus to the requirements of a reactive cassette.

      Reactive armor materials:

                                                                  ix.     ERA-light

      A sandwich of 3mm/3mm/3mm steel-explodium-steel.
      Requires mounting brackets of approximately 10-30% cassette weight.

      Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects).

                                                                   x.     ERA-heavy

      A sandwich of 15mm steel/3mm explodium/9mm steel.
      Requires mounting brackets of approximately 10-30% cassette weight.
      Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects).

                                                                  xi.     NERA-light

      A sandwich of 6mm steel/6mm rubber/ 6mm 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.

                                                                 xii.     NERA-heavy

      A sandwich of 30mm steel/6m rubber/18mm 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.     2A46 equivalent tech- pressure limits, semi-combustible cases, recoil mechanisms and so on are at an equivalent level to that of the USSR in the year 1960.

                                                                   ii.     Limited APFSDS (L:D 15:1)- Spindle sabots or bourelleted sabots, see for example the Soviet BM-20 100mm APFSDS.

                                                                  iii.     Limited tungsten (no more than 100g per shot)

                                                                  iv.     Californian shaped charge technology- 5 CD penetration for high-pressure resistant HEAT, 6 CD for low pressure/ precision formed HEAT.

                                                                   v.     The general issue GPMG for the People’s Auditory Forces is the PKM. The standard HMG is the DShK.

      c.       Mobility

                                                                    i.     Engines tech level:

      1.      MB 838 (830 HP)

      2.      AVDS-1790-5A (908 HP)

      3.      Kharkov 5TD (600 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- limited

      3.      Operational Requirements.

      The requirements are detailed in the appended spreadsheet.

      4.      Submission protocols.

      Submission protocols and methods will be established in a follow-on post, nearer to the relevant time.
       
      Appendix 1- armor calculation
      Appendix 2- operational requirements
       
      Good luck, and may Hubbard guide your way to enlightenment!
    • By Collimatrix
      Shortly after Jeeps_Guns_Tanks started his substantial foray into documenting the development and variants of the M4, I joked on teamspeak with Wargaming's The_Warhawk that the next thing he ought to do was a similar post on the T-72.
       
      Haha.  I joke.  I am funny man.
       
      The production history of the T-72 is enormously complicated.  Tens of thousands were produced; it is probably the fourth most produced tank ever after the T-54/55, T-34 and M4 sherman.
       
      For being such an ubiquitous vehicle, it's frustrating to find information in English-language sources on the T-72.  Part of this is residual bad information from the Cold War era when all NATO had to go on were blurry photos from May Day parades:
       

       
      As with Soviet aircraft, NATO could only assign designations to obviously externally different versions of the vehicle.  However, they were not necessarily aware of internal changes, nor were they aware which changes were post-production modifications and which ones were new factory variants of the vehicle.  The NATO designations do not, therefore, necessarily line up with the Soviet designations.  Between different models of T-72 there are large differences in armor protection and fire control systems.  This is why anyone arguing T-72 vs. X has completely missed the point; you need to specify which variant of T-72.  There are large differences between them!
       
      Another issue, and one which remains contentious to this day, is the relation between the T-64, T-72 and T-80 in the Soviet Army lineup.  This article helps explain the political wrangling which led to the logistically bizarre situation of three very similar tanks being in frontline service simultaneously, but the article is extremely biased as it comes from a high-ranking member of the Ural plant that designed and built the T-72.  Soviet tank experts still disagree on this; read this if you have some popcorn handy.  Talking points from the Kharkov side seem to be that T-64 was a more refined, advanced design and that T-72 was cheap filler, while Ural fans tend to hold that T-64 was an unreliable mechanical prima donna and T-72 a mechanically sound, mass-producible design.
       
      So, if anyone would like to help make sense of this vehicle, feel free to post away.  I am particularly interested in:
       
      -What armor arrays the different T-72 variants use.  Diagrams, dates of introduction, and whether the array is factory-produced or a field upgrade of existing armor are pertinent questions.
       
      -Details of the fire control system.  One of the Kharkov talking points is that for most of the time in service, T-64 had a more advanced fire control system than contemporary T-72 variants.  Is this true?  What were the various fire control systems in the T-64 and T-72, and what were there dates of introduction?  I am particularly curious when Soviet tanks got gun-follows-sight FCS.
       
      -Export variants and variants produced outside the Soviet Union.  How do they stack up?  Exactly what variant(s) of T-72 were the Iraqis using in 1991?

      -WTF is up with the T-72's transmission?  How does it steer and why is its reverse speed so pathetically low?
       
       
    • By Sturgeon
      This is the place for flame wars about rifle-caliber MGs versus autocannons for tank coaxial weaponry. First, we have Ensign's blog post about tank machine guns:
       

×
×
  • Create New...