DRDO Sarath Mortar Carrier

     Notes:  This mortar carrier based on the BMP-2 ICV is known officially by the Indian Military as the “Carrier, Mortar, Tracked” or simply “CMT.”  Like the Sareth itself (the Indian designation of the BMP-2S), the CMT is not regarded as having a bright future in the Indian Army.  The Indian Army has several problems with the BMP-2; chief among these is the relatively weak armor and the position of the fuel tanks.  Like the BMP-2, 61.5 liters of the fuel supply are inside tanks that are set within the doors, and the rest is in a large fuel tank in the centerline of the crew compartment. The Indians are currently considering a new base IFV, currently referred to as the FICV (Future Infantry Carrier Vehicle).  The CMT will probably last longer, though it has its own problems, such as the short-range in comparison to other 81mm mortar carriers and especially, 120mm mortar carriers.

     The 81mm mortar mounted in the CMT is a mid-range model, the IOF 81mm Mortar Type 1F. This is licensed copy of an Israeli-made mortar, the B-455. Like most such mortar carriers, the mortar must be lowered to a traveling position for major movements and then raised and locked in firing position again. The modified baseplate for use in the CMT built on top of the centerline fuel tank; a second baseplate is carried on the side of the vehicle, along with aiming stakes. The CMT also carries a standard aiming circle, along with grease pencils, rulers, protractors, etc., to be used if there is no FDC to provide firing coordinates or is no mortar ballistic computer is available.  Part of the space where the turret used to be is covered (primarily a small section at the front of the circle where the turret was and at the rear), has hatches which open to the left and right.  The mortar fires through this hatch space.  The mortar can be fired with an angle of 40 to 85 degrees, and traverse 24 degrees on either side without having to actually move the entire vehicle.  The mortar can be fired within 23 seconds of a halt, and brought back into traveling order within 30 seconds.  A mortar ballistic computer is provided, allowing the CMT to provide its own fire solutions.  However, the CMT can digitally transmit firing information, as well as the coordinates of the target, to other vehicles and mortar emplacements.  The CMT has a long-range data-capable computer and s short-range computer.  The mortar crew is separate from the driver and commander, instead of the commander and driver being part of the standard mortar crew of the CMT.

     Like the Sareth/BMP-2, interior space is limited, though this partially offset by the CMT not having a turret or ammunition for the turret armament. However, the CMT does have copious ammunition space, including the associated racks for the ammunition.  More space is taken up by the mortar itself.  The commander has a hatch on the front right, which is usually armed with an IOF MG-6A (license-produced version of the MAG-58 designed specially as a commander’s machinegun).  The commander’s hatch is surrounded by vision blocks, and has electric traverse (with manual backup.  The commander has a reticle on the forward vision block; this block can show the view using an image intensifier.  The MG-6A can also be aimed and fired (but not reloaded) from under armor and with the hatch closed.  The commander also triggers the smoke grenade launchers on the glacis (there are four on either side instead of the standard three). The driver is in the normal Sarath driving compartment on the front left above the glacis plate; he has vision blocks to his front and left side, as well as one that looks partially to the right side.  He can remove and replace his front vision block with a night vision block.

     Other than removal of the turret, the CMT has other differences between it and the Sareth.  All firing ports and associated vision blocks are deleted.  However, the twin rear doors, complete with fuel tanks, remain in place.  The commander’s periscope is omitted.  The CMT, like the Sareth, is powered by a locally-produced version of the UTD-20/3 turbocharged diesel providing 300 horsepower.  The driver and commander have use of a gyrocompass to help them navigate; this can also be of use when pointing the vehicle for proper employment of the mortar. The transmission is semiautomatic instead of being fully manual. Some sources say the Sareth is propelled in the water by its tracks, and others say that propulsion when swimming is switched to waterjets; I have not been able to determine which is correct.  If the Sareth is propelled by waterjets, they must be of low power, since the swimming speed reported in Sareths with waterjets of is not as high as most vehicles equipped with waterjets – indeed, no higher than standard Sareth reported as being propelled by their tracks. Amphibious operations can be dangerous in the Sareth, particularly in a strong current; and the suspension’s bearings are not airtight, and freeboard is not great.  The CMT has an NBC overpressure system for use when the vehicle is buttoned up and a collective NBC system for use otherwise.

     Twilight 2000 Notes: CMTs provided less than 1/10^th the mortar fire support for the Indian Army in the Twilight 2000 timeline.