Arjun Main Battle Tank (MBT)

[Bhadra]

No Kunal, finas are not to cause a spin, but to stabilize projectile during flight.

That is a good one. it means a spined discarding sabot has greater kinetic energy at impact

 

[Kunal Biswas]

No Kunal, finas are not to cause a spin, but to stabilize projectile during flight.

During flight of the projectile it have to spin to stabilize it self, for that fins are there..

That is the physics for any aimed projectile..

 

[Damian]

No, no, did any of You ever seen a slow motion video of a flying APFSDS penetrator? Fired from a smoothbore gun such penetrator barely spin, if it is spin anyway.

Search for such videos.

APFSDS round generally do not spin, but APDS rounds do spin because they do not have fins and are fired from rifled guns only, while APFSDS rounds might be fired by rifled and smoothbore guns. But as smoothbore gun do not have rifling, it does not cause spin effect on the round.

BTW HEAT rounds fired from smoothbore guns are also fin stabilized, and are not spining. So fins are not causing spin, if so, it would reduce effectiveness of HEAT rounds fired from smoothbore guns by causing spin effect that is not like by shaped charge warheads.

 

[LurkerBaba]

During flight of the projectile it have to spin to stabilize it self, for that fins are there..

That is the physics for any aimed projectile..

It's a bit more complex. A projectile with Fins does not spin, it uses the viscous property of air to stabilize itself. A Spinning projectile OTOH uses angular momentum

See this:


Aerodynamic Drag Stabilization vs Gyroscopic Stabilization

SPIN-STABILIZED PROJECTILES Most guns in use today use spin-stabilized projectiles. Spinning a projectile promotes flight stability. Spinning is obtained by firing the projectiles through a rifled tube. The projectile engages the rifling by means of a rotating band normally made of copper. The rotating band is engaged by the lands and grooves. At a nominal muzzle velocity of 2800 feet per second, spin rates on the order of 250 revolutions per second are encountered. Spin-stabilized projectiles are full bore (flush with the bore walls) and are limited approximately to a 5:1 length-to-diameter ratio. They perform very well at relatively low trajectories (less than 45� quadrant elevation). In high trajectory applications they tend to overstabilize (maintain the angle at which they were fired) and, therefore, do not follow the trajectory satisfactorily.

FIN-STABILIZED PROJECTILES These projectiles obtain stability through the use of fins located at the aft end of the projectile. Normally, four to six fins are employed. Additional stability is obtained by imparting some spin (approximately 20 revolutions/second) to the projectile by canting the leading edge of the fins. Fin-stabilized projectiles are very often subcaliber. A sabot, wood or metal fitted around the projectile, is used to center the projectile in the bore and provide a gas seal. Such projectiles vary from 10:1 to 15:1 in length-to-diameter ratio. Fin-stabilized projectiles are advantageous because they follow the trajectory very well at high-launch angles, and they can be designed with very low drag thereby increasing range and/or terminal velocity. However, fin-stabilized projectiles are disadvantageous because the extra length of the projectile must be accommodated and the payload volume is comparatively low in relation to the projectile length.

In contrast to conventional spin-stabilized projectiles which derive their in-flight stability from the gyroscopic forces resulting from the high rate of spin, the finned projectiles are stabilized during flight by aerodynamic forces acting on the projectile.

Although projectile spin does not contribute to the stabilization of finned projectiles, a low rate of roll around the longitudinal axis is desired to minimize the adverse effects of mass and configurational asymmetries which may result from material imperfections and from manufacturing tolerances.

Large Caliber Ammunition - Types of Projectiles

 

[Damian]

Thank You LurkerBaba.

 

[Shaitan]

Someone please tell what that green, square thing is on Arjun Mark 2.

Somebody posted this on BR... Can this really be the Arjun MK II (sexy looking beast)

 

[Kunal Biswas]

Someone please tell what that green, square thing is on Arjun Mark 2.

That is a radar for detecting tanks at long range and act as a radar range finder..

 

[Kunal Biswas]

Bigger Picture..

 

[Shaitan]

That is a radar for detecting tanks at long range and act as a radar range finder..

Share some images of it without it integrated to the tank.

I've only seen it in Saya's video capture.

 

[Kunal Biswas]

Share some images of it without it integrated to the tank.

Its a variant of BSFR..

http://drdo.res.in:8080/alpha/drdo/English/index.jsp?pg=battlefield.jsp

http://en.wikipedia.org/wiki/BEL_Battle_Field_Surveillance_Radar

 

[Scalieback]

In Punjab area, Engg & there Bridges decides the mobility of the army, though BMP & T-90/72, Arjun can do without one..

It doesn't seem to have a flotation screen so I assume it has a snorkel if you're saying it doesn't need to bother about bridges?

 

[Kunal Biswas]

It doesn't seem to have a flotation screen so I assume it has a snorkel if you're saying it doesn't need to bother about bridges?

BMP-2 swims, Arjun & Other tanks use Snorkel..

 

[Shaitan]

Its a variant of BSFR..

http://drdo.res.in:8080/alpha/drdo/English/index.jsp?pg=battlefield.jsp

BEL Battle Field Surveillance Radar - Wikipedia, the free encyclopedia

Awesome...

 

[Scalieback]

BMP-2 swims, Arjun & Other tanks use Snorkel..

I assume then that it's a seperate bit of kit and requires installation as it's not carried like Sov/Russ tanks. How deep?

What does India use as bridging units? Anything like the M3?

 

[Bhadra]

During flight of the projectile it have to spin to stabilize it self, for that fins are there..

That is the physics for any aimed projectile..

Is it applicable to artillery projectiles and mortars bombs to ? How does a moratr bomb spin?

 

[sayareakd]

one more thing about BFSR, it will be easy to hit, tanks and helicopter with LAHAT/CLGM including tracking of targets. New BFSR has double the range.

 

[Kunal Biswas]

I assume then that it's a seperate bit of kit and requires installation as it's not carried like Sov/Russ tanks. How deep?

What does India use as bridging units? Anything like the M3?

This Video is about Indian Army Corps of Engineers ( 10 min ) will give you deep insight..

Its in English..

Is it applicable to artillery projectiles and mortars bombs to ? How does a moratr bomb spin?

Mortar bombs have stabilizer fins at back, Arty shells spins as barrel is rifled..

Mortar barrel are rifled also smooth-bore..

 

[Folk hero]

Re: Arjun Mk-II Gets Ready To Compete Russian T-90 Tank

Is this Arjun mark 2?

http://frontierindia.org/forum/attachments/f4/641d1343468540-arjun-tank-mark-2-image-arjun-mak-2-image.jpg

 

[Kunal Biswas]

Re: Arjun Mk-II Gets Ready To Compete Russian T-90 Tank

Yes that is Arjun MK-2 Prototype Image..

 

[Shaitan]

Ok, I'm about to post Sengupta stuff...

This is one of two Arjun Mk1A MBT prototypes that are presently being subjected to mobility-cum-firepower trials. This photo, which appears in a four-page DRDO corporate advertisement published in the latest issue of THE WEEK magazine, was taken at the CVRDE's proving ground at Avadi earlier this year. The second Arjun Mk1A prototype comes outfitted with the new digital hunter-killer tank fire-control system, inclusive of a target auto-tracker and a newly-designed commander's panoramic day/night sight that incorporates an IRIS thermal imager (from France's SAGEM Défense Sécurité) and an eyesafe laser rangefinder. These optronic sensors are the same as that installed on the IRDE-developed commander's panoramic day/night sight which is presently undergoing user-trials on board an upgraded T-90S MBT.

TRISHUL


So if he's right. This isn't the picture of the mark 2 in trials.

And there isn't any pictures of the real deal yet.

I kind of believe it, because I'm not sure Thar has that type of red sticky soil.