the USA's new gun the M777
british built
The Ultralightweight Field Howitzer (UFH), designated M777 in the USA, was selected in 1997 by a joint US Army/Marine Corps initiative to replace the existing inventory of M198 155mm towed howitzers. The first of five EMD systems was delivered in June 2000. The US Marine Corps is to procure 380 systems and the US Army 273 systems. A Low Rate Initial Production (LRIP) contract for 94 systems was awarded in November 2002. US Army/USMC operational test and evaluation is scheduled to begin in August 2004. Full-rate production is scheduled to begin in 2005. The British Army is also expected to order 65 systems and the Italian Army 70 systems.
The M777 has been developed by BAE Systems RO Defence (formerly the Armaments Group of Vickers Shipbuilding and Engineering Ltd) at Barrow-in-Furness. United Defense LP of Pascagoula, Mississipi will be responsible for final assembly, test and delivery of production systems for the US.
The M777 is normally operated by a crew of eight men but can be operated with a reduced detachment of five.
M777 ARMAMENT
The XM777 matches the firepower of current generation 155 mm towed systems for less than half the weight. The Howitzer is equipped with a 39 calibre barrel. The muzzle velocity (at Charge 8 super) is 827m/s.
The maximum firing range is 24.7km with unassisted rounds and 30km with rocket-assisted rounds. The M77 will fire the Raytheon XM982 Excalibur GPS/Inertial Navigation-guided extended-range 155mm projectiles using the Modular Artillery Charge Systems (MACS). Excalibur will have a maximum range of 40km and accuracy of 10m. First firing trials of the M777 with Excalibur took place in August 2003.
The XM777 is able to deliver up to 5 rounds per minute under intense firing conditions and is able to provide a sustained rate of fire of 2 rounds per minute.
M777 FIRE CONTROL
The XM777 employs an optical sighting system for direct and indirect firing by day or night. The howitzer is compatible with digital fire control systems.
General Dynamics Armament Systems has been selected by the US Army to develop a towed artillery digitisation (TAD) system for the XM777. The TAD digital fire control system will provide onboard ballistic computation, navigation, pointing and self-location, providing greater accuracy and faster reaction times. The TAD program will also include a laser ignition system, electric drives for the howitzers traverse and elevation and a powered projectile rammer. The programme is to be completed in 2005 and will also be applied to the US Marine Corps systems.
M777 MOBILITY
The XM777 has a production weight of 3,745kg and can be transported by helicopter, transporter aircraft and ship. The howitzer can be towed by an air-braked 4x4 vehicle greater than 2.5t.
The hydrostrut suspension system is provided by Horstman Defence Systems of the UK. The maximum towed road speed is 88km per hour and the towed cross-country speed is 50km per hour. The load on the towing eye is rated at 60kg. The towing ground clearance is up to 660mm.
