FNSS Savunma Sistemleri AS, based in Ankara, Turkey, has completed the development of a new tracked armoured combat vehicle, Armoured Combat Vehicle - Stretched (ACV-S), under a private venture funding program. ACV-S was previously called ACV New Generation (ACV-NG). FNSS is jointly owned by United Defense of the USA (now BAE Systems Land and Armaments) and the Nurol Group of Turkey.

ACV-S is a stretched version of the FNSS ACV which is in service with the Turkish Land Forces, the United Arab Emirates and Malaysia and has been ordered by Jordan. The ACV has been deployed in Somalia, Bosnia and Kosovo with Turkish Land Forces in support of UN peacekeeping operations. Over 2,500 ACV vehicles have been ordered.

ACV-S features an extra roadwheel per side, which provides a longer and wider hull that allows the mounting of a two-man turret and also provides increased armour protection, mobility and payload capability.

The first two prototype vehicles were completed in 1998 and 2000. The vehicle is suitable for fast deployment by rapid reaction forces, requires no special permit for road transportation and is air transportable on a C-130 Hercules, C-141, C-17 and C-5 transport aircraft. The vehicle also provides amphibious operation, a high horsepower to weight ratio, high road speed and with the overall mobility to match modern main battle tanks.

The design of the vehicle is a derivative of the ACV-300 vehicle which itself was derived from one of the world's most widely deployed combat vehicles, the USA M113. The ACV-S has high commonality of components with the ACV-300 and the M113, which gives the advantage of reduced logistic requirements in spares inventories, training, reliability and maintainability.

The hull is wider and longer than the current ACV. The ACV-S provides more than 25% more accommodation under armour and a 70% greater payload capability compare to the M113 vehicle.

A power-operated ramp at the rear of the vehicle is used for fast exit and entry of troops and the ramp is also fitted with a door. Bench type crew seats along the centre of the troop compartment face outwards and firing ports and vision blocks are located on each side of the compartment.

The crew and engine compartments are fitted with a fire detection and suppression system. The vehicle is air-conditioned for operation in extreme conditions and equipped with a face mask or overpressure nuclear, biological and chemical warfare protection system.

The driver's station is at the front left of the vehicle and the engine is installed at the front right hand side. The driver uses four day periscopes. The forward periscope is replaced by a passive optical periscope for night-time manoeuvres.

The armour gives protection against 14.5mm armour piercing rounds. Optional add on armour kits and internal spall liners provide protection against 30mm ballistic rounds and rocket propelled grenades such the RPG-7 armed with high explosive anti-tank (HEAT) rounds.

For protection against mines the vehicle is fitted with a floor spall liner and 18mm armour plate in the floor. The vehicle is fitted with collapsible shock absorbing seats. The sponsons have additional armour which provides increased protection to the driver.

There are several roof hatch and turret options available which conform to the vehicle's maximum combat weight of 20t. The options include: one man and two men turrets with 25mm and 30mm cannon, a Stinger Air Defence Turret, TOW missile launcher turret, Ground Launched Hellfire turret, 90mm direct fire weapon, and a 150mm breech and muzzle loading mortar.

The ACV-S vehicle can be fitted with a one-man Sharpshooter turret developed by FNSS and United Defense. This is a variant of the two-person Bradley Infantry Fighting Vehicle turret designed by United Defense. The turret is fitted with an ATK Gun Company 25mm M242 cannon and a 7.62mm coaxial machine gun. A prototype vehicle has also been built with a Thales AFV Systems SWARM turret, with an ATK Gun Systems Company 12.7mm gun.

The ACV-S Eryx Squad Vehicle carries a fully equipped squad of soldiers and is armed with the Eryx anti-armour-missile system.

The ACV-S has also been fitted with the turret of a BMP-3 infantry combat vehicle, produced by Instrument Design Bureau (KBP) of Tula, Russia. The system is called ACV-SW. The BMP-3 turret is armed with a 100mm 2A70 semi-automatic rifled gun/missile launcher, which can fire either HE-FRAG (High Explosive-Fragmentation) rounds or the 9M117 laser beamriding anti-tank missile.

The ACV-S is equipped with a Detroit Diesel 6V-53T turbo-charged diesel engine, rated at 350hp, and an Allison X-200 series automatic transmission system. The vehicle accelerates from 0km/h to 30km/h in 7.5 seconds and the maximum speed on a metalled road is 75km/h.

Alternative engine options to meet the customer country's logistical requirements include the Detroit Diesel 6V-53TIA, rated at 400hp, which is fitted with built-in diagnostics, and an MTU diesel engine with a ZF automatic transmission.

The vehicle is fitted with an upgraded suspension system with improved final drives. Each side of the suspension system comprises six roadwheels with a front drive sprocket and a rear idler but no track return roller. The roadwheel travel is over 380mm which gives improved mobility across rough terrain. The upper part of the suspension is covered by a protective skirt.

The Armoured Combat Vehicle - Stretched, currently developed as an infantry fighting vehicle, can be configured in a number of variants including a command post, forward observation, artillery rocket vehicle, engineer vehicle with a dozer blade, recovery vehicle with a winch and stabiliser blades, ambulance, air defence vehicle and reconnaissance vehicle. The installed systems can be integrated with a military standard data bus.