Arjun Main Battle Tank (MBT)

[ersakthivel]

@ersakthivel, first you said LOS behind main sight is 630 mm, then 800 mm now 900 mm

630 mm if we just correct the wrong 1080 mm dimension to 1300 mm approx according to the faulty 3D model from @Dejawolf (without taking the correction for wrong positioning of the gunner's seat which will add another 300 + mm and take it to the real value of close to 900 mm..)

 

[ersakthivel]

@ersakthivel, first you said LOS behind main sight is 630 mm, then 800 mm now 900 mm



I finally see your argument properly now, but the yellow line should not be that behind the main sight, you are cutting some poor guy's head into two pieces.

OMG, That means you don't understand what I am saying at all.

@Dejawolf has positioned the gunner 300 mm in front of where he actually must be.

What I am saying is that the gunner must be pushed back to a position between the red and yellow line as per the photo.

No need to compare to Dejawlf's model any more to comment on the correctness of my model. If you find any issues in my drawing comment on a stand alone basis. And I will clarify it.

 

[The Last Stand]

OMG, That means you don't understand what I am saying at all.

@Dejawolf has positioned the gunner 300 mm in front of where he actually must be.

What I am saying is that the gunner must be pushed back to a position between the red and yellow line as per the photo.

I did understand he has placed gunner's seat in front, but I didn't think it was such a large value like 30 cm

 

[sayareakd]

I think it should be like this

 

[The Last Stand]

I think it should be like this

Sayare sir, you have placed the gunner a bit far back. He should be a little closer to the aiming devices.

 

[ersakthivel]

I think it should be like this

Thanks,


Correct Sir. That is what I am trying to get across for the last 30 pages.

 

[ersakthivel]

Sayare sir, you have placed the gunner a bit far back. He should be a little closer to the aiming devices.

The aiming device will also need to come back to a position close to the gunner to reflect the reality of thicker LOS behind the main sight..Like in the picture.

Now I hope all your doubts are clarified.

 

[sayareakd]

Sayare sir, you have placed the gunner a bit far back. He should be a little closer to the aiming devices.

Point is not that first commander's seat should be made proper as it is necessary to go in and out of tank for both the gunner and commander. As you can see hatch line drawn with blue color is the line of seat. Now at the foot of the commander, gunner sit, you can also see their is not much room for him to move forward or backward as we can do in our chair.

Therefore this is only one 2D pic.

 

[sayareakd]

Sayare sir, you have placed the gunner a bit far back. He should be a little closer to the aiming devices.

another matter of common sense is this post

IA has raised problems with almost every issue with Arjun except for front armor, So if they have issues with the weak front armor, then you wont find change front armor on the main sight side in MK-2 version.

It also appears that DRDO dont have any issues with armor at the front near the main sight.

 

[Dejawolf]

It is your thinking that is coz of lack of knowledge, My measurements are not wrong but accurate..

And cannot be of others either, Pixal is approx and proven wrong already..

well, the planetary trajectories are approximations, and yet we've managed to send rovers and probes to mars based on these approximations.
your argument is pixel measures are unusable because they are approximations. i find that a little silly.
how far was i off? 5cm? 10cm? on a poor picture too.if it had been the front it would have been a lot easier to estimate height, because we have the known width of the arjun. here i had to additionally estimate the height of the hull to have a point of measure, on a picture with a slight perspective distortion.

 

[Dejawolf]

It is your thinking that is coz of lack of knowledge, My measurements are not wrong but accurate..

And cannot be of others either, Pixal is approx and proven wrong already..

I think it should be like this

commander needs 63cm of space for his legs and knees.

other than that, backrest of commander is pretty much in that spot already in my model.

 

[Dejawolf]

another matter of common sense is this post

it's fairly simple. if you put armour in front of the sight, you cannot look out of it anymore. to fix the weakspot, you'd have to redesign the entire turret.

 

[ersakthivel]

commander needs 63cm of space for his legs and knees.

other than that, backrest of commander is pretty much in that spot already in my model.

You are saying that "commander needs 63cm of space for his legs and knees."

Are those 63 cms seen here in the photo below. A big No. Why?

Because of the height differential. Most of the 63 cms allowance for commander's knee length passes over the head of the gunner.

And it is commander's foot that is behind the back rest of the gunner, Not commander's knees.

Gunner sits atleast 300 mm below the height at which you put him in the 3d model.

The distance between the Tc's seat front edge and the back rest of the gunner's seat cannot be more than 50 mm according to the picture above, which is indisputable.

In your 3 D model it is much more than that.Close to 250 mm approx as per your 1 meter marking.

.If you make the correction mentioned above you can easily see the 1 meter mark extending up to the inside opening for roof top vision block inside crew compartment.

You can easily see the big black handle like knob which is at the same point as that of Tc's front edge of the seat bisecting the distance between the Tc's head rest and the roof top vision block opening inside the crew compartment.

This distance is just a meter. Because the distance between the head rest of the TC and the front edge of the Tc's seat cannot be more than 1 meter.

Also where is the roof vision block opening inside the crew compartment?

AFAIK it is between the orange FCS box and gunner's main sight vision block you marked in red. The photo above clearly shows that.

Because the top of the orange FCS box is not visible in the photo. But the roof vision block opening is visible below the bottom of the orange FCS box.

If the roof top vision block opening inside the crew compartment is as shown in your 3D model. There is no chance for the vision block to be visible in the photo above.

Because the orange FCS box and the roof vision block are so close to each other. So there is no way that roof top vision block is going to be visible below th bottom of the orange vision block as per the photo.

Do you agree?

 

[Dinesh_Kumar]

Sakthivel Sir,

I don't know who is correct , but from your knowledge and dedication abt Arjun, hats off to you.

Please also give some posts abt 120mm Rifled main gun.......

I heard that ARDE Director Trained in UK, and our gun closely related to theirs (Challenger), hence one of few rifled guns in the world.

Hoping more interesting posts from you.

The photo below is further proof that distance between gunner's seat back and the and the opening of the roof vision block inside crew compartment(red and yellow lines ) is same as the distance between the driver seat back rest and Tc's seat back head rest(black and red lines ).

 

[ersakthivel]

commander needs 63cm of space for his legs and knees.

other than that, backrest of commander is pretty much in that spot already in my model.

Also where is the roof vision block opening inside the crew compartment?

AFAIK it is between the orange FCS box and gunner's main sight vision block you marked in red. The photo above clearly shows that.

Because the top of the orange FCS box is not visible in the photo. But the roof vision block opening is visible below the bottom of the orange FCS box.

If the roof top vision block opening inside the crew compartment is as shown in your 3D model. There is no chance for the vision block to be visible in the photo above.

Because the orange FCS box and the roof vision block are so close to each other. So there is no way that roof top vision block is going to be visible below the bottom of the orange vision block as per the photo in case your 3D model is corect.

So one of the two must be wrong depiction. Which one? The photo or your model?

Do you agree?

 

[ersakthivel]

Sakthivel Sir,

I don't know who is correct , but from your knowledge and dedication abt Arjun, hats off to you.

Please also give some posts abt 120mm Rifled main gun.......

I heard that ARDE Director Trained in UK, and our gun closely related to theirs (Challenger), hence one of few rifled guns in the world.

Hoping more interesting posts from you.

Thanks Sir,

I don't know much about the rifled gun of Arjun other than one very interesting post from some one called Denil of israeli efence establishment , which is already posted here.

Iam arguing my view point based on the engineering drawing principles of machine design , side view, plan view and front elevation which is taught in 2nd year mech eng classes and the principles of perspective drawing . That's all I know.

Based on that I am pointing out glaring mistakes in some of the posters view point.

Because in Engineering drawing all parts positioned in all three views namely plan ,elevation and side view must be at the exact dimension points respective to each other.

Even if one or two does not match then the explanation is wrong.But in the 3D models lot os the parts won't match their respective position according to the photos.

So what I did was to place them in their respective position according to all three views called plan ,elevation and side view to arrive at a correct drawing. So there is no way one can dispute it.

And I have no sources in defence establishment.

And also this long argument is based on photos of various old aprototypes and one line drawing of Arjun and has no relation to the production model Arjun tanks serving in the India army now,

In the production models arrangements may be entirely different from than these old prototypes.

However even based on these old prototypes the so called theory of 380 mm LOS for armor behind the main sight for Arjun falls flat on it's face,

So it is quite evident that Arjun has robust protection levels all around according to Indian army GSQR and not glaring weakness there and here, which surprise of surprises has not been noticed by the indian army , the israeli experts or the CVRDE for 3 decades , but visible straight to these guys across seven seas who have no proper knowledge of any principles of engineering drwaing or taking measurement on proper planes in perspective drawing

So they are repeatedly arriving at a very wrong conclusion and want all others to believe it , because they have some access to some facts and modelling softwares.

 

[Dejawolf]

Sakthivel Sir,

I don't know who is correct , but from your knowledge and dedication abt Arjun, hats off to you.

Please also give some posts abt 120mm Rifled main gun.......

I heard that ARDE Director Trained in UK, and our gun closely related to theirs (Challenger), hence one of few rifled guns in the world.

Hoping more interesting posts from you.

if you followed this discussion in full you wouldn't be giving such praising words, as you'd see some of the frankly ludicrous assessments that erhsaktivel makes, like gunner having to be behind gun mantlet, insistence on what is obviously storage boxes being addon armour, claiming the arjun mk 1 had blowoff panels when that was clearly impossible, (and which was later confirmed as an upgrade for mk. 2) claiming arjun gun armour is so thick that the breech would reach all the way back into the turret bustle where the ammunition is located, mistaking an arjun for a tank-ex, claiming arjun has 1800mm of front turret armour, and all sorts of other crazyness.
you'd do well not to listen to anything he says.

 

[Kunal Biswas]

Read your post again, you will find your work ditch when you are claiming to be precious..

how far was i off? 5cm? 10cm?

 

[sayareakd]

First go through the height standard of Indian army then go forward.

Indian Army Physical Standards

Not everyone in India is 6 feet that require 63 cm for legs and knees.

 

[Dejawolf]

First go through the height standard of Indian army then go forward.

Indian Army Physical Standards

Not everyone in India is 6 feet that require 63 cm for legs and knees.

no but the space you've marked off is 40cm leg space for TC which is tiny.