HISTORY
The GCT is a self-propelled howitzer based upon the chassis AMX-30 main battle tank. Giat started the development in 1969 when the French government announced the AXM 105 and Mk.F3 were to be replaced. The new self-propelled howitzer was to have a long range and a high rate of fire. The development was named GCT by Giat. GCT stands for Grand Cadance de Tir, French for high rate of fire. This name was chosen while it had a rate of fire which was twice of what was normal at the time. The first prototypes were built in 1972 and the vehicle entered production in 1977. In French service the GCT was called the AUF-1. The GCT was exported to a few nations in the Middle East.
DESIGN
The GCT is based on the chassis of the AMX-30. The driver is seated on the left side of the chassis while the remaining three crewmembers are seated in the turret. The commander and gunner are seated on the right and the loader on the left. Most of the armour is removed making the chassis 2000 kilograms lighter. The ammunition stowage for the 105mm tank shells has been replaced by an APU allowing the GCT to function without a running engine. The huge boxy turret is fitted with a 40-calibre 155mm howitzer fitted to an automatic loader. The ammunition is placed in seven racks of six similar shells. The whole rear of the turret can be opened to allow the racks of six shells and the charges to be loaded quickly. A 7.62mm AAT-F1 or 12.7mm M2HB is mounted at the loader’s hatch. Furthermore the GCT is fitted with 4 smoke grenade launchers. The GCT was fitted with very modern fire control systems, including a goniometer, an optical goniometer, a contrarotation device and a direct fire sight.
Upgrades
A total of 74 GCT are fitted with even more sophisticated fire control systems. These vehicles are known as AUF-1T and are only used by the French army. In 1999 a project was started to upgrade most of the French AUF-1 to AUF-2 configuration. The AUF-2 has an improved APU and engine, is fitted with a 52-calibre barrel, a modified recoil system, an improved automatic loader, a muzzle velocity radar and has a multi round simultaneous impact (MRSI) capability. The four smoke grenade launchers are replaced by the Galix system which is also fitted to the Leclerc.
PERFORMANCE
When the GCT was introduced it was the best operational self-propelled howitzer. The range and rate of fire was and is much better than the US M109 or Russian 2S3. The accuracy was similar. Only the South African G6 Rhino had a longer range and better accuracy. During the 1991 Gulf War the GCT was together with the T-72 the only non-air defence vehicle to be a primary target for US combat aircraft. The US Army feared that the GCT could be used for counter battery fire beyond the range of their own artillery. Most Iraqi GCT’s were hunted down by aircraft and taken out by bombs and missiles before they could be put into use.
Firepower
It takes one to two minutes for the GCT to come into action. The turret can be traversed a full 360 degrees and the armament can be fired in all directions. It is possible to fire a burst of six rounds in 45 seconds. The normal rate of fire is 4 to 6 rounds per minute and during sustained fire 1 to 2 rounds are fired every minute. The maximum rate of fire with manual loading is 2 to 3 rounds per minute. The high rate of fire creates a near similar effect as the multiple round simultaneous impact (MRSI) capability of the newest howitzers. The improved AUF-2 has a MRSI capability. The typical load outs are 36 (6x6) HE shells and six (1x6) smoke shells or 30 (5x6) HE shells, six (1x6) illuminating shells and six (1x6) smoke shells. The maximum range with standard HE ammunition is 23 km, with US M107 rounds its 18 km and HE BB rounds have a range of 29 km. The 52-calibre gun will improve the maximum range to 39 km. While the armament isn’t stabilized the GCT can only be used for direct fire when stationary, making it an easy target. The 7.62mm AAT-F1 machinegun has 550 rounds ready to fire and a total of 2050 are carried. The M2HB heavy machinegun has 100 of its 800 rounds ready to fire. The armour protects the crew from shell splinters and heavy machinegun fire. The Galix system of the AUF-2 should increase the survivability of the crew. The improved AUF-2 has a MRSI capability.
The GCT is a self-propelled howitzer based upon the chassis AMX-30 main battle tank. Giat started the development in 1969 when the French government announced the AXM 105 and Mk.F3 were to be replaced. The new self-propelled howitzer was to have a long range and a high rate of fire. The development was named GCT by Giat. GCT stands for Grand Cadance de Tir, French for high rate of fire. This name was chosen while it had a rate of fire which was twice of what was normal at the time. The first prototypes were built in 1972 and the vehicle entered production in 1977. In French service the GCT was called the AUF-1. The GCT was exported to a few nations in the Middle East.
DESIGN
The GCT is based on the chassis of the AMX-30. The driver is seated on the left side of the chassis while the remaining three crewmembers are seated in the turret. The commander and gunner are seated on the right and the loader on the left. Most of the armour is removed making the chassis 2000 kilograms lighter. The ammunition stowage for the 105mm tank shells has been replaced by an APU allowing the GCT to function without a running engine. The huge boxy turret is fitted with a 40-calibre 155mm howitzer fitted to an automatic loader. The ammunition is placed in seven racks of six similar shells. The whole rear of the turret can be opened to allow the racks of six shells and the charges to be loaded quickly. A 7.62mm AAT-F1 or 12.7mm M2HB is mounted at the loader’s hatch. Furthermore the GCT is fitted with 4 smoke grenade launchers. The GCT was fitted with very modern fire control systems, including a goniometer, an optical goniometer, a contrarotation device and a direct fire sight.
Upgrades
A total of 74 GCT are fitted with even more sophisticated fire control systems. These vehicles are known as AUF-1T and are only used by the French army. In 1999 a project was started to upgrade most of the French AUF-1 to AUF-2 configuration. The AUF-2 has an improved APU and engine, is fitted with a 52-calibre barrel, a modified recoil system, an improved automatic loader, a muzzle velocity radar and has a multi round simultaneous impact (MRSI) capability. The four smoke grenade launchers are replaced by the Galix system which is also fitted to the Leclerc.
PERFORMANCE
When the GCT was introduced it was the best operational self-propelled howitzer. The range and rate of fire was and is much better than the US M109 or Russian 2S3. The accuracy was similar. Only the South African G6 Rhino had a longer range and better accuracy. During the 1991 Gulf War the GCT was together with the T-72 the only non-air defence vehicle to be a primary target for US combat aircraft. The US Army feared that the GCT could be used for counter battery fire beyond the range of their own artillery. Most Iraqi GCT’s were hunted down by aircraft and taken out by bombs and missiles before they could be put into use.
Firepower
It takes one to two minutes for the GCT to come into action. The turret can be traversed a full 360 degrees and the armament can be fired in all directions. It is possible to fire a burst of six rounds in 45 seconds. The normal rate of fire is 4 to 6 rounds per minute and during sustained fire 1 to 2 rounds are fired every minute. The maximum rate of fire with manual loading is 2 to 3 rounds per minute. The high rate of fire creates a near similar effect as the multiple round simultaneous impact (MRSI) capability of the newest howitzers. The improved AUF-2 has a MRSI capability. The typical load outs are 36 (6x6) HE shells and six (1x6) smoke shells or 30 (5x6) HE shells, six (1x6) illuminating shells and six (1x6) smoke shells. The maximum range with standard HE ammunition is 23 km, with US M107 rounds its 18 km and HE BB rounds have a range of 29 km. The 52-calibre gun will improve the maximum range to 39 km. While the armament isn’t stabilized the GCT can only be used for direct fire when stationary, making it an easy target. The 7.62mm AAT-F1 machinegun has 550 rounds ready to fire and a total of 2050 are carried. The M2HB heavy machinegun has 100 of its 800 rounds ready to fire. The armour protects the crew from shell splinters and heavy machinegun fire. The Galix system of the AUF-2 should increase the survivability of the crew. The improved AUF-2 has a MRSI capability.