Arjun Main Battle Tank (MBT)

Austin

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FORCE

Pressure on the Ground
Arjun Mk-2 offers enhanced firepower, but it's too heavy to go where the Army wants it
By Atul Chandra

Avadi, Chennai: After more than three decades of development, India's Arjun Main Battle Tank (MBT) has literally emerged like a phoenix from the ashes, surprising even its most sceptical observers. Last year, the Arjun outgunned the Indian army's T-72 and T-90 MBT's, when trials were conducted with the respective units putting up their best tanks and personnel.

FORCE visited the Combat Vehicles Research & Development Establishment (CVRDE) for an exclusive insight into the programme. We learnt that while the Arjun Mk-2 is substantially improved and more capable than the Arjun Mk-1; it is too heavy, limiting areas where it can be deployed by the Army. And that renders it unsuitable for the army's operational requirements for a Main Battle Tank (MBT). According to P Sivakumar, Director CVRDE, "the weight of the Arjun prevents it from being deployed in all the areas required by the Army".



Keeping this in mind, the Arjun Mk-2's improved performance seems to have put the Army in a spot. What does one do with a tank that is fast, can shoot accurately on the move and is relatively well protected but is too heavy to be deployed in the deserts near the Pakistan border as a replacement for the T-72 or T-90? Paradoxically, while the tank itself has demonstrated high speed and mobility, its weight precludes it from being able to operate anywhere the army wants it to. The Arjun Mk-2 will weigh around 67 tonnes and this fatally limits the tank's operational effectiveness for the Indian Army.

The tank is too heavy to be deployed across the border with Pakistan. It is unable to effectively traverse terrain filled with natural and/or artificial obstacles. Or areas criss-crossed with rivers and canals. That rules out most places in Rajasthan, Punjab and the mountainous terrain of the J&K sector.

This has forced the army to identify areas where the Arjun can safely be deployed and its operational units based. This probably means the Arjun will not fight alongside the T-90s and T-72s. It will certainly not be part of the Indian Army's strike corps formations, as it could get bogged down in unfamiliar terrain. This runs counter to the philosophy of armoured formations, which are designed for mobile offensive operations deep inside enemy territory. Unlike the T series tanks that have been airlifted to high altitudes like Leh and even out of the country, the Arjun cannot be airlifted by the IL-76 and C-130 J transports of the Indian Air Force (IAF). The C-17 Globemaster to be inducted by the Indian Air Force (IAF) has a maximum payload of 75 tonnes — insufficient to airlift the 67 tonne Arjun Mk-2 with attendant support equipment.

During this correspondent's visit to the CVRDE facility at Avadi in Tamil Nadu, it was evident that despite the best efforts of its highly committed team of designers and scientists, the Arjun is unlikely to ever be ordered in significant quantities by the Indian Army — which fields close to 3,500 tanks in its Order of Battle (ORBAT). The total orders for the Arjun as of today are 240 (124 Mk-1 and 116 Mk-2). For the Army, ordering more tanks would result in it having to devote more resources — something it seems loath to do.
As things stand presently, the first Arjun Mk-2 will roll off the production line at Heavy Vehicles Factory (HVF) Avadi, two and a half years (30 months) after the order is placed. With the orders likely to be finalized towards the end of the year, the first Mk-2 tank will enter operational service in 2016. With HVF Avadi looking at a production rate of 30 tanks a year, all 116 tanks will be delivered by 2020. If work on the Future Main Battle Tank (FMBT) begins now in right earnest, then the first tanks could be ready for operational service circa 2025. Until then, the army would rather soldier on with its T-90 and upgraded T-72 tanks, which in any case have the required infrastructure in terms of training, manufacture and overhaul.

The major improvement in the Arjun Mk-2, is its missile firing capability from the gun barrel. This was demonstrated in 2004, with Israel Aerospace Industries' (IAI's) Laser Homing Attack/Anti Tank Missile (LAHAT). But the tank did not have an integrated Laser Target Tracker (LTT) at that point of time. That is now in the final stages of inspection and is being demonstrated to the user. The army has also asked for more types of ammunition on the Mk-2. This includes Thermobaric rounds and Penetration cum Blast rounds that will be developed in India. Thermobaric warheads create a sustained and intense pressure wave, which can be used against bunkers and hardened targets, while causing minimum damage to the surrounding areas. The army has also asked for two types of practice rounds, including blank rounds for ceremonial purposes. These will also reduce wear and tear on the barrel during training. In terms of protection, the Mk-2 will have full frontal Explosive Reactive Armour (ERA) and since commonality was desirable, it will use the same structuring as the T-series. The Defence Research & Development Organization (DRDO) is re-developing the explosive element, which is currently Russian, with better protection capability. It is being developed at the High Energy Materials Research Laboratory (HEMRL). This will be used for the Arjun, T-90 and T-72 tanks. Active Protection Systems (APS) that help evade attack — both by confusing enemy sensors (soft-kill) or by physically destroying incoming warheads (hard-kill) — will also be incorporated on the Mk-2.

The Israeli 'Trophy' system is being considered for the Mk-2. There will also be a mine plough to deal with pressure based mines, magnetic mines and tilt based mines. The driver's seat on the Mk-2 is now suspended from the roof, compared to being fixed to the floor on the Mk-1 — this provides better mine protection capability. With the Explosive Reactive Armour (ERA) and mine plough together weighing 3 tonnes and additional add-ons expected, the MK-2s weight is expected to increase from 62 tonne to 67 tonne. The suspension has been re-designed to handle 70 tonne. To cater to complaints of track shedding, the revised tracks will have an increased horn length (19 mm) and the wheels have become slightly bigger. The tracks are imported from Germany but the rest is indigenous. The engine will remain the same on the Mk-2. With the original power pack on the Mk-1, the final drive catered to a top speed of 72 kmph. For the Mk-2, the final drive has been changed by increasing the reduction ratio from 4.4 to 5.3 and the top speed is now reduced 58.5 kmph but the torque and the force available at the contact between the track and the road has increased which can cater for the increased weight. Despite the increased weight, CVRDE claims that the acceleration is better than the Mk-1, while fuel efficiency remains the same.



The Arjun Mk-2 programme also suffered a severe setback with the unfortunate demise of senior scientist G K Kumaravel a few months ago. Kumaravel died in a road accident, while at Pokhran for trials of the Arjun Mk-2. He was heading the Arjun programme and slated to take over as Director, CVRDE in the future. He had played a crucial role in the developments and system integration of the Arjun MBT Mk II. The Arjun programme will now be led by V Balamurugan. The biggest problem being faced by the Arjun and a fate that is shared by almost all other indigenous programmes, is the small numbers ordered — that precludes investment in the required production and tooling. Sivakumar told FORCE that "Greater numbers are essential for reducing the price, establishing the process, good quality control mechanisms and continuous consistency in production". This is also the reason he says that orders are a must. The Heavy Vehicles Factory (HVF) has not been producing Arjun MBT's for two years and lot of the know-how is being lost.

WWhile officials at CVRDE say the Army has been happy with the performance of the Mk-1, FORCE learnt that non-availability of spares is a continuing problem — the usage of spares was greater than anticipated. There have been complaints of track shedding, though CVRDE officials say that's caused by inexperienced drivers who're used to the T-72 and T-90. The 120 mm tank gun has been proved on the Mk-1 series and today, the Arjun barrel offers better life when compared to the T series of tanks. There have been barrel issues on a few tanks and a committee is looking into the matter, according to CVRDE officials.


Tank commander inside Arjun Mk-2 tank

The process of obtaining replacement spares is time consuming, since there are a number of agencies involved. Limited production numbers further exacerbate the problem. Director Sivakumar told FORCE that steps were being taken to tackle this problem and "unlike the Mk-1, where orders for the tank and the Engineering Support Package (ESP) were handled separately, in the Arjun Mk-2 this will be done simultaneously. That will reduce the time taken for delivery of the required items". According to him, production has improved dramatically and an Israeli firm is now working on computerization of the line.

Meanwhile, the Indian Army is struggling to maintain its ageing fleet of T-72 MBT's. While the T-72 was acknowledged to be one of the finest Russian tank designs, the ageing tank fleet is now increasingly difficult to maintain. Its small size and cramped turret make it difficult to incorporate the latest technology — like fire control systems, night vision and electronics. Unfortunately for the Army, the T-90 has not proved to be as sterling a performer as its predecessor. A number of glitches have come to the fore and production at HVF has been slow to take off. Russia has also refused to transfer technology related to metallurgy for T-90S gun barrels and armour plates to the HVF.

Despite all that, the Arjun outgunning the T-90 and T-72 in comparative trials, is akin to the Light Combat Aircraft 'Tejas', defeating the F-16 in a dogfight! The units that took part in the competition put up their best tanks and crew. The Arjun managed to fare very well. Army sources have freely admitted to FORCE, that there is a mind block with regard to the Arjun, by those who have operated the T series tanks. But they also admit that the Arjun is appreciably more modern in comparison to the T-72 & T-90, in many respects. For example, the Arjun can fire almost twice the number of rounds the T series tanks can, from its main gun.

The Arjun Mk-2 in many ways is what the Arjun Mk-1 should probably have been. Tragically, total orders for the Arjun over the next decade are unlikely to exceed 400 to 500 units including the 240 already ordered, plus other variants like the Armoured Repair and Recovery Vehicle (ARRV), Catapult 130 mm Self Propelled Gun and SP-155 gun chassis. The last refers to a tracked base that was to be mated with a Slovakian gun, in collaboration with Bharat Earth Movers Limited (BEML). That proposal has already run into rough weather. It remains to be seen if the army will accept such indigenous offerings or prefer to go abroad for proven systems, which can be inducted quickly and in meaningful numbers, to arrest the alarming decline in its armoured and artillery capability.


Arjun Mk-2 during firing trials

What is however clear is that continued production and development of the Arjun must be allowed to continue, if critical design, development and production know-how is not to be frittered away. It is also essential to keep the production line functional — through manufacture, repair, overhaul and upgrades, till the Future Main Battle Tank (FMBT) programme begins to gather steam. Keeping this in mind, it is likely that the DRDO will be able to prevail on the army for a few more orders, to enable low-rate production to continue. It is imperative that the DRDO and the Army move faster on the FMBT programme, to ensure that it is ready in time to replace the T-72.

In all, the army's armour profile through 2015-2020 could comprise of approximately 1700 T-90S, 1800-2000 upgraded T-72M1s, and 250-500 Arjun's. Surely, prospective orders for the FMBT, which at the very least would be for 1000-1500 tanks, are incentive enough for this to be taken up as a national project. This futuristic tank is unlikely to cost less than Rs 50 crore a piece — the total orders would be worth Rs 50,000 to 75,000 crore.

Training Tools
The Arjun also features a state of the art simulator facility for training of drivers and crew. Canada-based simulator manufacturer CAE developed and delivered the initial suite of Arjun tank training systems, to efficiently and cost-effectively train the driver, gunner and commander in the Arjun tank. The Arjun tank training system offers: standalone training for the driver and gunner; turret level training for the gunner and commander; integrated tank level training for the gunner, commander and driver; troop level training, by networking Arjun tank simulators to rehearse troop tactics, movement and joint operations.

CAE's Arjun tank training system comprises a CAE Medallion-6000 visual system, with a detailed, realistic external environment view of actual tank operations. It also has a sound simulation system, which produces sounds heard during tank operations, synchronised with the motion and visual cues in the training device. There's a simulation host system for software management and software sub-systems to simulate tank behaviour in real-time operations. Also on offer are content rich geo-specific databases; an instructor station to conduct training exercises & offer evaluation solutions; an Interface Electronic Unit (IEU) to provide a link between tank crew controls and simulation software; and networking, to connect the Arjun driving and turret simulators.

The driver trainer for the Arjun is mounted on a six Degree-of-Freedom (DOF) motion platform. It faithfully emulates the interior cabin of the tank. There is also the Arjun turret simulator, to replicate the interior of the gunner and commander stations. Mounted on a six DOF motion platform, the Arjun turret simulator features a 220 degree by 40 degree open hatch visual display, to provide trainees with the high-fidelity visual cues required for gunnery training.

Fists of Iron
The quest to indigenously design and develop a Future Main Battle Tank (FMBT) by the Defence Research and Development Organization (DRDO), must be accorded the status of a national project, if it is to succeed. The prize could be a minimum order of at least a thousand tanks, to replace the Indian Army's T-72 tanks, starting 2022.

It is more likely that the FMBT will be ready only around 2025. DRDO will require at least a decade to have the first examples ready for trials and then roll out production variants a few years later. While the estimated development cost of Rs 5,000 crore might seem large, the investment would pay itself back many times over. An order for 1000 FMBT's would be worth Rs 50,000 crore (Rs 50 crore per piece) over two to three decades. It would boost indigenous Tier-1 and Tier-2 industries involved in the programme.

The FMBT at present is expected to be a highly mobile Main Battle Tank (MBT) in the 50-55 tonne class. It would have the latest technology, like advanced materials to keep the weight down, a smooth bore 120 mm main gun capable of firing missiles and advanced munitions, a modern, high powered engine (1800 hp) with state of the art transmission, suspension and running gear. It will incorporate a high level of crew protection, through use of next-generation Active Protection Systems (APS) to supplement its armour protection. It will also provide a high level of situational awareness to the crew through sensors, data links and the ability to operate in a networked battlefield.

While the Army has asked CVRDE to refrain from talking about the programme, work has already begun on the engine development — a good sign for the programme. Interestingly, companies like Renk and AVL have refused to provide consultancy for engine development. The development of the 120 mm smooth bore main gun will also provide its own challenges, in terms of design and weight. Keeping in mind the Israeli involvement in the Arjun programme, it is very likely that Israeli companies will play a vital role in the development of the FMBT.

CVRDE has gained considerable experience in tank design and development with the Arjun and Arjun MK-2 upgrade. Designing a 50 tonne tank with the features demanded by the Army, will be an extremely difficult task. However many of the parts of the FMBT are likely to be indigenous — such as the power pack, suspension and running gear, 120 mm smooth bore main gun, explosive reactive armour (ERA) panels, communication and data link sets. Facilities would have been set up by then for either joint production, or license manufacture of night sights, targeting and fire control systems etc.
 

Austin

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FORCE

Interview: Director, CVRDE, Dr Sivakumar, gives us the low-down on the Arjun programme.

'At Present, the Army has Decided to Induct 118 Arjun Mk-2 Tanks Instead of 124'

What is the status of the Arjun Mk-2 programme currently?


The Arjun Mk-1 with a total of 89 improvements decided upon with the Army, is called the Arjun Mk-2. These 89 improvements have been made not only keeping in mind the concerns and issues faced on the Arjun Mk-1 tank but also to cater for future requirements of the army. At present, the army has decided to induct 118 Arjun Mk-2 tanks instead of 124. This is the result of a policy decision that will see the war reserve for all armoured regiments in the future being reduced by three. And so, two regiments of Arjun Mk-2 will be short of six reserve tanks. The indent for 118 tanks is almost in the final stage.



Director, CVRDE, Dr Sivakumar, gives us the low-down on the Arjun programme

The army has said that it will decide if it is satisfied with the Arjun Mk-2, only after the trials (which began last month and are expected to go on for two to three months) are completed. The Ordnance Factory Board (OFB) will require 30 months (2.5 years) from the placement of the order, for the first batch of Arjun Mk-2 to be delivered to the army. The Mk-2 will incorporate all that we learnt while battling issues with the Arjun Mk-1, in terms of production, performance, quality etc. CVRDE is working to ensure that whatever problems were faced by the Mk-1 will not be repeated in the Mk-2. Based on the Mk-2 programme, we have formed a core committee called the Arjun Core Committee that will monitor the progress of the Arjun Mk-2 on a monthly basis. All the stakeholders starting from the DRDO, the Directorate General of Quality Assurance (DGQA), the Corps of Electronics & Mechanical Engineers (EME) and the users, are present on the committee and we have obtained excellent support from all the stakeholders.

What are the major changes in the Arjun Mk-2?

The Arjun Mk-2 will see the tank weight increase from 62 to 67 tonnes, as a result of specific requirements from the user — which include additions such as the track width, mine plough and Explosive Reactive Armour (ERA) on the glacis plate, as well as the front of the turret. These two requirements alone will add three tonnes to the weight of the Arjun Mk-1. Along with other additions, the Mk-2 is expected to top out at 67 tonnes. We decided after studying the power pack (MTU engine with RENK transmission), that it is excellently suited for Indian desert conditions. We have steadily made this engine and transmission more and more rugged over the last many years, besides improving things like the air filtration system and cooling system.

Hence, we have convinced the user that the same power pack, with a new final drive using a higher reduction ratio, can be used for the Arjun Mk-2. This was proved to the Army last year, when we drove 1350 km with the power pack modified to this standard and simulated weights of up to 66 tonne. We converted production vehicle P-1 into Mk-2 with 53 improvements, to obtain feedback. This tank took part in an exercise last summer that lasted almost two weeks, with temperatures of 46 degrees. We have improved the suspension — to provide the same life to components despite the increase in weight. To cater for this new suspension, we have developed a new hull for the Arjun Mk-2.

The Mk-2 variant is now capable of firing missiles, which was not possible in the Mk-1. We had already proved the LAHAT missile as a standby. We are now integrating it on the Mk-2. Apart from that, the Mk-2 will feature a remote controlled weapon system atop the turret. In Mk-1, this required the loader to come out and fire the weapon. The Mk-2 will have an improved commander's panoramic sight with night vision, hunter killer capability between the commander, gunner and loader. Auxiliary Power Unit (APU) which is not present in T series tank is present. It has been enhanced from 4.5 kW to in excess of 8 kW for the Mk-2. With regards to the Chassis Automotive System, we have digital communication systems, advanced navigation systems etc. We have increased the track width, to ensure that the ground pressure remains the same in spite of the increased weight.

What is the status of the Arjun Mk-1 at present?

The Arjun Mk-1 received orders for a total of 124 numbers. The two regiments equipped with 45 Arjun tanks each, are the 43rd armoured regiment and the 75th armoured regiment at Jaisalmer. The Arjun is fully operational with these two regiments now. The balance 34 tanks will be used to meet the Army's BRIC requirements and these are spread across the Corps of Electronics & Mechanical Engineers (EME), war reserve, training establishments, DRDO/DGQA etc. Heavy Vehicles Factory (HVF) Avadi has dispatched 116 Arjun Mk-1 tanks. The remaining eight tanks will be delivered over the next five to six months.

Most of the spares for the Arjun MBT were consumed during the various trials. We are now working to ensure availability of fresh spares. The other part is the Engineering Support Package (ESP) for the Arjun which includes spares, training and training aids. This is being done in parallel. As far the Arjun Mk-1 is concerned, about 90 percent of its tasks are complete.

What is the cost of the programme till date?


Each Arjun Mk-1 costs Rs 20 crore plus. Each Arjun Mk-2 with all improvements will cost approximately Rs 34 crore. The Arjun Mk-1 programme cost approximately Rs 360 crores. With that money, we made 11 prototypes and 15 pre-production series tanks and the required spares. This included the cost of creating the production line. We are looking at a number of variants based on the Arjun platform, such as Armoured Repair and Recovery Vehicle (ARRV) which is close to finalization. We are also looking to use the Arjun chassis to mount a Russian 130 mm Catapult gun, which was earlier mounted on the Vijayanta chassis. We will also be competing for the Indian Army requirement for a self propelled, tracked gun. We will offer a Slovakian 155 mm gun mounted on the Arjun along with Bharat Earth Movers Limited (BEML).

We have also built the Arjun Bridge Laying Tank (BLT) but the Army says it may not be required. The cost per tank will certainly go down if we get more orders. This will help reduce the import content as well. The Mk-1 has nearly 60 percent imported content and even though there is a lot of value addition being done, the import content will remain the same for the Mk-2.

Since the size of the order is small, no foreign company is willing to offer Transfer of Technology (ToT). I feel that if the Mk-2 is ordered by four regiments, then the import content could go down to 43 per cent and further down to 25 per cent if orders are placed for a total of six regiments. The lifecycle costs of the Arjun will be much cheaper than other tanks. The programme has also been able to offer numerous improvements to a number of indigenous programmes and armoured vehicles in service with the army.
 

Damian

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I do not understand why they left suge huge unprotected weakened zone. Dynamic protection coverage should be as tight as possible, such solution would not be acceptable anywhere else.

Did they really have not find better place for that radar antenna and were unable to change configuration of the main sight placement?
 

Austin

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I do not understand why they left suge huge unprotected weakened zone. Dynamic protection coverage should be as tight as possible, such solution would not be acceptable anywhere else.

Did they really have not find better place for that radar antenna and were unable to change configuration of the main sight placement?
They I think didnt want to change the configuration and used ERA where ever possible to imrove protection.

Arjuns front is already very high in western heavy standard so ERA would just make it better for what was already good , what it needs is ERA on side which is what it has got.

The Manlet may be weak area but they will have to redesign the whole stuff and make it small , ERA cant go there.

The area for Radar or what ever it is ( IFF ? ) is a bit strange though because it vulnerable to stastically the area where it will take more hits.
 

Damian

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They I think didnt want to change the configuration and used ERA where ever possible to imrove protection.
Not the best idea in a long term perspective.

Arjuns front is already very high in western heavy standard so ERA would just make it better for what was already good , what it needs is ERA on side which is what it has got.
You know, weight is not nececary protection level indicator. And then theres more. Arjun have less of it's surface protected by composite armor (only front of turret and hull) while NATO MBT's have more surface protected by composite armor (front and sides of the turret + hull front). This means that Arjun having such configuration might use less weight efficent armor to probably achieve similiar levels of frontal protection.

The Manlet may be weak area but they will have to redesign the whole stuff and make it small , ERA cant go there.
To the contrary, ERA can be placed there without any significant problems.

The area for Radar or what ever it is ( IFF ? ) is a bit strange though because it vulnerable to stastically the area where it will take more hits.
It would be better to place it somewhere on turret rear, to be automatically hidden in lightly armored box when not needed. Something similiar to Russian BRM-1 or it's analog "Svatava" from former Czechoslovakia.
 

Kunal Biswas

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I do not understand why they left suge huge unprotected weakened zone. Dynamic protection coverage should be as tight as possible, such solution would not be acceptable anywhere else.

Did they really have not find better place for that radar antenna and were unable to change configuration of the main sight placement?
One Good reason is the increased weight forced the deginers to keep ERA limited, Other wise i see no problem applying the same ERA over Sides in similar config as T-90MS..

Good Question, They could have used the radar at top in fold-able manner..



This is not good, The major deign flaws in Leo A4 are kept ignored, I wonder why no one studied that Why Leo-A4 deign was changed in Leo A5 and further..
 

Rahul Singh

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That's a compromise as it looks but it may not be final configuration. I expect part of the area around main sight to be protected by ERA in final configured vehicle.
 

Pandora

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well i want to see it like this



Red is radar, black ERA and Blue area is for RCWS.
Overall, it's good to see some important improvement however they still left some areas of weekness here . Like They didn't cover the left frontal turret with ERA. Hope this is not the final version.
 

Rahul Singh

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How wrong i would be if i say FMBT will be scaled-down Arjun (i am talking about hull)?
 

Kunal Biswas

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At the moment, The best one can do is to do little modification with given time and work on FMBT or Arjun MK-3
 

sayareakd

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Kunal sir, Arjun MK-II should have engine at the front, with unmanned turret, two man crew and drive by wire tech and full auto loader. That will be true future tank.
 

Kunal Biswas

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Kunal sir, Arjun MK-II should have engine at the front, with unmanned turret, two man crew and drive by wire tech and full auto loader. That will be true future tank.
Engine is good if its at back, the Reason is Merkava front Hull protection is poor..

Simple way is to have a heavily Armour 5-6 wheel Chassis with a unmanned turret housing a powerful yet lighter 120mm cannon..


--------------------

Btw, this are our Ideas and I seriously doubt anyone in give serious thinking..
 

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