BAE Systems has celebrated the delivery of the 500th M777 howitzer to the US military.
Weighing in at under 4,200kg, the revolutionary M777 is the world's first artillery weapon to make widespread use of titanium and aluminium alloys, resulting in a howitzer that is half the weight of conventional 155mm systems.
US Army officer Colonel James Matties said that BAE had achieved a magnificent job in support of operations in Iraq and Afghanistan.
BAE Systems's artillery programmes director Ian McMillan said that this was a landmark moment for a transatlantic programme which has hit every milestone along the way.
"M777 follows two other Anglo-US weapon success stories - the 105mm light gun and the 81mm mortar are both British BAE Systems designs which have been adopted by the US" McMillan said.
BAE Systems global combat systems facility at Barrow-in- Furness is responsible for the prime contract management of the M777 programme, including direct customer liaison and acceptance of the weapon system in the US, control of the UK and US supply chain, engineering design authority and manufacturing and assembly of the complex titanium structures and associated recoil components.
Most of the 500 M777s have been delivered to the US Army and US Marine Corps. Canada also has 12 M777 howitzers in service with the Royal Horse Artillery. Both nations' services operate M777s in Afghanistan, providing fire support to coalition forces. The gun is known by local insurgents as the 'desert dragon'.
The M777 can fire the 'smart' Excalibur round, co-developed by Global Combat Systems up to 40km (25m) accurately enough to target individual rooms within a building, reducing the chance of innocent casualties and allowing supporting fire to be brought down much closer to friendly troops.
The M777 can hurl a standard 43.5kg shell almost 30km (21 miles) at 2.5 times the speed of sound. The projectile takes just over a minute to fly this distance and reaches a maximum height of 12km. The shell reaches its maximum speed of 2,900km/h (1,800mph) by the time it exits the muzzle of the gun.
The energy released firing at maximum range is 40MJ, which is the equivalent of accelerating 55 family cars to 45mph in just 12 thousandths of a second.
The internal cannon peak pressure during firing reach 60,000lb/in².
The wind speed, meteorological conditions and even the earth's rotation all have to be taken into account for accurate targeting.
The gun remains stable when firing, despite its light weight, by being 'out of balance' - the barrel is mounted low and forward to prevent the gun overturning when it is fired.