Further Discussion of the Tankita.

See here for the first page.

        The Stormer 30 is nearly a Tankita, and gives a good idea what such a vehicle might look like.  The true Tankita would be based on M113 parts rather than a Scorpion/Spartan chasis, so we can probably expect better amphibious performance.  The Stormer 30 uses a 275hp engine, like current M113A3 variants.  The IFVL has already demonstrated a 400hp engine.  This means the Tankita would either be faster and more nimble than the Stormer, or can carry more armour with the same performance.  Modular armour systems would allow the vehicle to be either high speed or well defended, depending on role. 
        The Hybrid Electric/diesel system mentioned already has been tested on M113s and has an output of 500hp in addition to being quieter and more fuel efficient.
        The Tankita would probably mount a pod of 2.75" FFAR rockets in addition to the ATGWs.  A Bofors 40mm gun might be used instead of the 30mm Bushmaster II of the Stormer. 

Ralph Zumbro, Author of "Tank Sergeant", writes about the Hybrid drive M113/4:-
        "Phil, The one I was in, and it may be the only one, is state of the art.  They steer it with a Bradley gunner's control and it will run for an hour at 30mph on two batteries which are in boxes sized approximately 18"x36"x48".  Then a standard issue genset cuts in.  The motors are rated at 250 hp each and are oil cooled.  It is weird to see a 3 inch diameter drive shaft coming out of a motor the size of a 5 gallon can. 
        The rubber tracks are soundless, and they've got 2500 miles on them with very little wear showing.  That adds up to a VERY quiet vehicle for recon work.  Put electric motors, rubber tracks and a two man turret with a 30mm gatling weapon on a standard 113 hull and you've got a recon Tankita.
        The reason for the suggestion of the gatling is that a three bbl version would be compact.  We are talking the straight case version of the 30mm here, the cartridge for the Aden/Defa type gun (30x113mm).  If you control the motor you can fire singles, bursts, or dump at 3000 rpm on hostile armor and chew his vehicle to shreds while you make the hasty exit.
         I mentioned to the people at United Defense that not needing air for the engine made the vehicle capable of running around UNDER water and was told that that had been thought of.  That means that you could add enough armor to stop larger weapons, as long as you don't compromise the mobility."

        The idea of mounting a 30mm Gatling gun similar to that of the A-10 on a vehicle has occurred to many people, although maybe the four barreled GAU -13 is more practical, or a pair of Boeing Bushmaster II cannon. 
        Bill Clarke points out that the 30x173mm APDU round can penetrate 200mm of RHA, and that an APDSDU version would perform even better.  Since a GAU-13 can fire at 35 rounds per second a Tankita equipped with such a weapon would have a very credible performance against both MBTs and Helicopters. 
        This discussion about the anti-tank capabilities of small calibre high-velocity rounds made me consider further the idea of a Tankita equipped with a 76mm gun.  The South African GT-4 is claimed to have a muzzle velocity of 1600m/s (5248fps) with APFSDS rounds, suggesting that this is not just a Light Armour killer.I have been able to find out that the GT-4 is a rifled gun, and has the same chamber dimensions as the Otobreda Compact Naval Gun (also used on the OTOmatic AAA tank).  The GT-4 has a HE-T round and an APFSDS-T round claimed to be effective to 2000m.  Shells for the naval gun can also be used if they are changed from mechanical to electrical priming.  Rate of fire is given as 6 rounds per minute. 
        The 30mm gatling or 76mm gun could be supplemented by ATGWs mounted on the Tankita.
        During the '80s several prototype vehicles were built mounting a 75mm ARES gun.  A vehicle mounting this weapon is shown here.  Note that the "history" given is fictional for use with "Twilight 2000", more's the pity.

        The above vehicle is in reality AAI's RDF/LT armed with the 75mm ARES gun.  This was a 13.4t vehicle and it was claimed 8 could be carried in a C-5, 2 in a C141 and 1 in a C130.  The CH-47 and CH-53 could also carry the RDF/LT as an underslung load. 
         The gun had a high rate of fire, and was fed by a 60 round carousel.  Penetration of the 75mm APFSDS is claimed to be equal to that of the 105mm M774 APFSDS round. 
More Images of the RDF/LT
Czech site on the RDF/LT

        There were two interesting variants of the RDF/LT.
         The first was the CAT/LCV which had improved air defence capability.  As well as the 75mm ARES gun and different fire control system it could also mount eight Stinger or six Bofors RBS70 surface to air missiles in pods on the side of the turret.  Apart from the missile pods this externally resembles the RDF/LT.  A proximity fuse HE shell is used for anti-aircraft fire.  An impressive feature of the AAI/ARES turret is not only its low profile, but that the main armament is capable of a very high elevation.  Not only is this useful for the air-defence role, it also gives the 75mm gun an indirect fire range of 12,000m.  The CAT/LCV or a vehicle like it can handle the tasks of air defence, anti-tank and support fire, making it a useful system for forces whose assets are limited.
         The second version was geared for export, and used a long barreled 76mm gun that could use the same ammo as the weapon of the M41 Chaffee tank.  The 76mm APFSDS round developed for this is claimed to be as effective as a 105mm HEAT round at 1500m, and only slightly less effective than the 105mm M753 APFSDS at the same range. 

On the subject of the 75mm ARES gun Mike Sparks passes on the following information:-

        "Mike, when I was chief of the Land System Division at the Defense Advanced Research Projects Agency (DARPA), I started a project called Armored Combat Vehicle Technology.  ACVT was soon embraced by GEN Bernard Rogers, C/S Army, and BG Al Gray, Director of Combat Developments at Quantico.  Our primary objective was the development of a helicopter-transportable light tank.  I contracted with Gene Stoner at Ares for the development of a 75mm High Velocity Automatic Cannon, and with Win Barr at AAI Corp for the development of the 75mm telescoped ammunition (a depleted uranium Armor Piercing Fin Stabilized Discarding Sabot round and a High Explosive Air Defense round with Navy Mark-404 IR proximity fuze). 
        AAI also built a 14.5 ton light tank using a cut down M113A3 chassis.  We put on a demo at the Boeing Plant in Philadelphia carrying the light tank under a CH-47D helicopter on a short sling flying nap-of-the earth at 110 knots.  The gun fired at a rate of 1 shot per second.  A burst of 4 shots was enough to bring down a jet fighter flying evasively at about 4000 meters range and kill a Hind or Havoc Helicopter at about 4000 meters range (both with a probability of a kill of about 90%.  A 3-shot burst with APFSDS rounds would kill a T-72 Tank head-on at about 2000 meters range with a probability of kill at about 90%.  I believe that the light tank is in a combat vehicle museum in Manassas, VA.  I also believe that Ares still has a 75mm cannon at Port Clinton, Ohio, along with a number of rounds of ammunition.  TRASANA at White Sands ran a Force-on-Force Carmonette simulation that showed the Light tank performing better than the M-1 tank in a delaying action scenario in the Fulda Gap in Germany.
        I contacted the Asst.  Commandant at the Air Defense School at Fort Bliss who was very much interested in the 75mm gun, but the missile advocates picked the Martin Air Defense Anti-tank (ADATS) system which turned out to be too expensive; so the Air Defense guys wound up with a Stinger mounted HMMWV instead.  The multi-purpose 75mm gun is by far the most cost-effective anti-tank/assault/anti-aircraft weapon system!"
Very Respectfully,
Charlie Lehner

Bill also adds.
        I like the idea of vehicles mounting both cannon and missiles.  I would mount the Hellfire ATGM in 2x3 cell launchers on the Tankitas, but would also have IFVs with only the gun (for purposes of weight and cost). 
        Also, the GAU-13 is an externally driven weapon, it's ROF could be easily set to a level that would be within the capabilities of the firing platform's recoil capacity.  On a heavier Tankita, it could be set to the max.  of 2,100rpm.  On a LAV sized vehicle, you could set it for around 800-1000rpm.
        Also, it has a dual feed mechanism, so separate ammunition drums could be attached, giving the gunner the flexibility to engage with the appropriate ammunition type.  Checked on the dual feed with an A-10 crewchief.  Not used on the A-10, but it is a feature of the weapon.
        I think I would use twin 1,170rd A-10 type ammo drums for Tankitas, and a single 1,170rd ammo drum for a IFV.  I would estimate that a 1 second burst(35rds) of 30mm 2:5 ratio (14 HVAPDSDU, 21 HEDP) would be more than enough against a T-80 or older tank, which would result in the ability for the IFV to kill up to 33 tanks with one drum- out to a range of about 1,500M.  Surely, a 1 second burst would decimate any fortification that may be encountered.  Remember, the HVAPDSDU rds also carry an incendiary effect, due to the pyrophoric nature of DU238.
        Also, there's no question of the effect such a mix of ammo would have against personnel, light vehicles, and aircraft of all types.  Not even an A-10 could withstand 35 hits of the above mentioned ammo. 

        Further, I would arrange my structure into teams, with 3 IFVs operating with 2 Tankitas.  This would give each Plt/section 5 GAU-13's, 12 Hellfires, and 24 dismount infantry.  I believe this would be a very powerful mix of forces/weapons.  One final consideration that leans heavily in the rotary cannons favor is the huge psychological impact that 5 30mm gatling cannons would cause to the enemy.  Having seen actual A-10/Avenger live-fire demonstrations, I can say that the sound is terrifying and LOUD!

        I'm actually preferring the 75/120mm more than the GAU-13 for the Tankita the more I think about it. 
        I think there's a good possibility that a 75mm with a 120mm NATO CASE would be the best tank-killing main gun round of all time, with APFSDSDU.  Buildings and machine gun nests would also be easily within it's engagement parameters. 

        A 75mm gun can have a proportionally longer barrel for the same weight.  This suggests a slow burning propellant would be a useful characteristic of the round, accelerating the projectile right out to the muzzle.
        The first ever anti-tank rifle round was 13mm, but performance was greatly improved when a 7.92mm bullet was fitted instead.  The same sort of idea was done with the 30x173mm round- a disproportionately large case, similar to a milk bottle in size.  The 75mm round you suggest is a logical further scale-up, but would also exploit discarding saboted shot.  A 3" shell should be sufficient for most non-MBT targets such as IFVs, buildings, machine gun nests and snipers. 
        I'd opt for a 76mm weapon so we can utilize shells already in production for weapons like the GT-4 and OTOmatic
        I can see the 76mm-Tankita armed with a mix of APFSDSDU, HESH (HEP) and Canister rounds.  A proximity fuse HE or HE-frag shell may also be used for air defence or indirect fire tasks. 
        The longest 75mm tank gun barrel that I recall was 70 calibres, which by my calculations gives an interior volume of around 9.2 cubic metres.  Question is, do you really need the powder capacity of a 120mm casing to create that much propelling gas? 
        An alternate idea is a 76/90mm round.  For a barrel of 9.2 cubic metres volume I have a suspicion that the 90mm case will have all the powder capacity you will need -having a smaller overal round will allow more rounds to be carried, the automatic loader to be lighter and less lugging for the crew when restocking the loader-plus the 90mm guns on many armoured cars or older tanks could be modifed and improved by just fitting a new (and probably lighter) barrel. 
         A configuration that I suggest for the 76mm armed Tankita as well as other Light and Medium vehicles I call MAGAMAS (Mobile Armoured Gun And Missile Armed System).  This is a vehicle equipped with a direct fire gun and several ATGW launchers.  The vehicle also has a light cannon (30mm ASP) to conserve main gun ammo.  Ideally the turret will be unmanned and operated by the crew in the hull.  The turret also mounts a mast mounted sight/sensor system. 
        One option is to have the cannon and MG both mounted on smaller turrets, one on either side of the main weapon.  A similar type of cleft turret was used on the experimental T92 The smaller turrets can either be locked forward to fire co-axially or can traverse independently, useful in close terrain were attacks can come from several directions in a short space of time. 

More on the T92
T92 Top view

        Yes, I agree.  A 75/120mm APFSDS would be best suited to a slow burning propellant, and a nice long tube.  The velocities that a 75/120 could reach are almost unbelievable.  Figure 20% MORE than the current US 120mm APFSDS.  Almost rail-gun like speeds!  The 75mm would still be able to pack an adequate explosive charge for light armor and fortifications, I agree. 
        I know I would DEFINITELY like to see a 75/120mm on our M-1's.
        The 75/120 would be larger, but not too bad.  An M-551 type chassis should still be able to carry 30+ rounds of ammo.
        If a 25mm saboted round was used, as you've proposed, A/R would climb to 15:1 or greater.  This would lead to a velocity loss in the area of only 25-30fps:100m.
        The GT-4 76mm produces 1,600m/sec(5,000fps), the 75/120mm would produce velocities around 7,500+fps (2,400m/s) I understand your apprehension about developing a new round, but it would not be all that difficult.  The standard breech assembly of the US Rhienmetal 120mm mated to a standard 120mm barrel machined for the 75/120mm case.  It would be quite a simple modification to existing production facilities, as opposed to the creation of BRAND NEW production facilities for the ARES, which was only a prototype.  The 75/120mm would actually be the cheaper way to go-and clearly the most effective.  I highly doubt the 75mm ARES sabot could penetrate the frontal slope of ANY Western Chobham armored MBT.  The 105mm DEFINITELY cannot. 
        I was referring to APFSDS.  US tankers regularly practice using 120mm Sabot against attack helicopters.  A good gunner can score close to 70% kills in simulation with the current round.  The 120mm APFSDS is just so fast, combined with the excellent gyro-stabilization and FLIR of the M-1 that a chopper at a range of 2 miles or less, even moving at 100kts, is not a very hard target to hit.  Particularly the gigantic machines the Russians seem to like.
        Now, a 75/120mm with 20% MORE velocity AND a 2nd GEN.  FLIR would make it child's play.  'Fast Movers' are still out of the question though. 
        This brings me back to the GAU-13.  A GAU-13 equipped AFV would CLEARLY outperform either a 75mm, a 75/120mm, or a 30mm or 40mm single or twin gun design against tactical attack fighters.  When you lack a dedicated AA targeting system, there is simply NO substitute for ROF.  A GAU-13 equipped vehicle has the ROF to hit an airborne target without needing serious computer/radar assistance.
        A GAU-13 @ 2,100RPM and 4,200fps (or 4,400+fps with your proposed shallow-rifling), with a 2nd GEN.FLIR is CLEARLY the best choice against 'fast movers'.  It would also easily eclipse any of the other primary armament configurations for target (infantry) suppression as well. 

        A good case can be made for using the M-551 Sheridan chassis for a Tankita, as opposed to an M-113. 
  1. The M-551 has a MUCH lower profile, making harder to see and hit. 
  2. It's suspension is already designed to bear the weight of a steel armor package.
  3. It is already configured for air-drops. 
  4. It has demonstrated the ability to provide a stable firing platform for a 152mm gun-launcher.
  5. It's frontal armor is at a much steeper angle than the M-113, greatly increasing protection.
  6. We already have hundreds of 'em, and they SUCK as presently armed.
  7. Since we already have hundreds of 'em, their infrastructure and supply chains are fully in place.
  8. Our ABN.  soldiers are already familiar with the vehicle, and our maintenance personnel are fully trained to service and repair them.

        I just don't think it'd be a great idea to modify an APC to be a Tankita, when we've already got a Tankita now that needs serious upgrading.  Killing two birds with one stone is always the way to go if you can. 
        To me, the ULTIMATE Tankita is based on the M-551hull, with ERA block add-on armor, equipped with a low-profile 1 man Chobham turret, and an autoloading gyro-stabilized 75/120mm gun- Targeted by a 2nd Gen 360° independently rotating Flir turret, with full ballistic solution, and the JTIDS data system.  Operated by a two man crew.  I would mount an SUU-11 7.62mm 6bbl mini-gun as the co-axial weapon.

        Here, you would have a vehicle that could out-gun today's heavies, with excellent mobility, good infantry suppression ability, excellent anti-helicopter capability, and very good armored protection- All in an existing air-droppable package. 
        To me, the only question is whether it could handle the recoil of a 75/120mm.  If not, even a 75/105mm would GREATLY increase the lethality over an ARES 75mm OR GAU- 13, and has already been proven to work just fine on vehicles of this size.  I'd try everything to make a 75/120mm work.  Failing that, I'd go 75/105mm, which we already know would work.

         An interesting argument, though I would point out that the Tankita I propose is based on a M113 hull, it does not use one.  The hull would be lower and the armour sloped.  The Tankita would be related to the M113 in much the same way the Scorpion is related to the Spartan. 
        On the Original Tankita page there are some interesting arguments in favour of a three man crews over two.  These are summed up quite nicely in this Russian article on Future tanks.

"Automation of the crew's operations will reduce its number to two men.  However, proceeding from functional considerations it is expedient to retain the three-man crew to allow one of them to focus his attention on the battlefield, enemy and cooperating tanks, orientated on the terrain and maintain communication with superior commanders.  Automation of the crew's operations will reduce its number to two men.  However, proceeding from functional considerations it is expedient to retain the three-man crew to allow one of them to focus his attention on the battlefield, enemy and cooperating tanks, orientated on the terrain and maintain communication with superior commanders."

        Remember, if we arm our IFVs with GAU-13's, there's no reason we can't ALSO mount ATGM/FFAR pods as well.  I just don't think they'd be necessary with my version of the Tankita operating in organic plt.  sized teams.
        However, I'm not one to complain about extra firepower, so I'm onboard with the "OMNI-PODS" if you guys still see a need for them.  I'm just trying to keep cost in consideration here, that's all. 
        There's no need to design any new mobile mortar carriers, the US M106 4.2" is already based on the M-113, and would fit right into the scheme of operations for an AIR-ARMORED Division.  Maybe an upgrade to a 120mm breech-loader, but that's about it.  They're already assigned in sections of two per company, so the TO&E is already established.

        Three mortars in a company allows them to be attached to platoons.  I'd prefer to see 81mm mortars retained at company level, probably in a gun-mortar equipped vehicle that also carries a M252 for dismounted firing.  The 81 has a shorter minimum range, and is better suited to dismounted operations.  In certain situations the vehicle could bring both mortars to bear onto a target, which for a three vehicle section would mean about 180 rounds arriving every minute

        Also, we already have the M-113 based FIST-V FO vehicle with full TACAIR integration and laser designating turret. 
So, as a force structure breakdown-

We'd have 3 plts of 3 IFV and 2 Tankitas. 
Three companies per bn for a total of 45 vehicles, and 216 heavily armed dismount infantry. 

        I like the idea of a force that can form Platoon combat groups of 4 IFVs and 3 Tankitas.  This is a bit like the Armd Cav "troops" used in Vietnam, but without the shortage of infantry.  This arrangement also gives the platoon commander an additional MG/Light mortar team, and you still have mortar capability if a company mortar team is not attached.  Two of the Tankitas would have 76mm guns, and the third a GAU-13.  The last would handle airborne threats or attack ground targets
        The 76/90mm armed Tankita would be the modern weapon system closest in capabilities to the German Flak 88s. 
        The Tankita has obvious capabilities against armour and strong points and is more maneuverable and better protected than the 88. 
        In indirect fire 76mm shells may not break up an armoured formation like 155mm, but they will certainly be effective against infantry, which are likely to be a more common target in future conflicts.  And it is worth mentioning that a Tankita used for indirect fire would not be replacing 155mm artillery, but supplementing it. 
        A Tankita firing APFSDS or proximity fuse shells will bring down the most heavily armoured helicopters.  How effective the gun will prove against fixed wing aircraft without the complexity of a radar system is uncertain.  Possibly the Tankita's fire control could be slaved to another vehicle mounting a radar system.  Guided projectiles are also a possibility.  Tankita mounting 30mm GAU-13 cannon have obvious ground to air and anti-vehicular abilities. 

HHC would have six M-106 SP mortar carriers, and 3 FIST-V's, as per today's Armored TO&E.  Further, an HHC level Plt of 3 Tankitas for scouting purposes.

        I'd prefer a force of 120mm Assault Gun Mortars in place of the muzzle loading mortars. 

At the regimental level (3 Bns), we have our Coy.  of Apaches (9 birds), and a battery of UH-60 Indirect AIR ROCKET ARTILLERY (9 birds), using both standard and blast/frag Hellfires.  Plus our battery of towed 105mm Howitzers (6 tubes), and our company of UH-60 transport choppers. 

2 regiments of as composed light airborne, plus a third regiment of "our" Armored Airborne", and we have the force structure we need. 
        Of course, divisional would have another 9 Apaches, 9 UH-60 ARA's, and 6 more 105mm's, plus a company of UH-60 transport choppers, and a company of CH-47D Heavy lift choppers. 
        Using today's US Army TO&E structure, that's how this would all boil down. 

         Part of the indirect ARA concept is that any helicopter can be used to deliver rocket artillery fire, so I'm thinking of that nine bird unit in the regiment or division as more of a cadre and supply unit for all of the formation's birds when in an ARA role.  Lighter 105mm and 155mm SPHs are a possibility instead of towed systems. 

Ralph Zumbro also adds:-
Ref Tankita armament.  Something you may not know about the 30mm round.  If you have dual feed and are in an urban area.  The TRAINING ammo gives a remarkably good imitation of a solenoid jackhammer when applied to cinder block construction...If coupled with a rocket laucher that can heave HESH into cement construction, you have a very good wall breaker. 

        The training round is basically a stack of washers in an aerodynamic shell.  The idea was to create a round that does not ricochet and carry long distances when fired air-ground from an A-10.  When I heard about these it did occur to me that there might be other uses.  These would certainly be effective against personnel and buildings, but might also reduce the risk of unwanted fires or shoot through endangering relatively close non-combatants.

        The French AMX-13 FOV is a good example of what we could do with the M113 -it has a well armed light tank, an IFV, two models of enclosed 105mm SPH and a light 155mm SPH (the F3).  Singapore uses the AMX-13 as its primary battle tank. 

        An AMX type turret mounted on a front engined Tankita would give a Merkava style layout.  The rear compartment can easily be loaded with extra ammo and this can be used to reload the turret bustle revolvers from the top hatch in the rear of the hull. 
        This layout gives simpler vehicle reload, simpler weapon reload, and the potential of carry scout teams like the FCS proposal.  The rear hatch could also be used to mount one or more machineguns or grenade launchers that can engage targets in a different quadrant from those that the turret is firing on.  A couple of dismounts can also provide local security or act as a relief crew. 

Ralph Zumbro suggests:-
        A Tankita or tank gun armed Bradley could be paired with a M113 full of dedicated armored infantry.
        Call five pairs like this a "doubled platoon" and add a resource sergeant with a couple of M548s and you've GOT something.