In his late February 2010 testimony on the posture of the United States Marine Corps, presented to the United States Senate Armed Services Committee, Commandant of the Marine Corps Gen. James T. Conway observed, “We are modernizing Marine Corps land-based fire support through a triad of weapons systems – a new and more capable 155 mm howitzer, a system of land-based rockets, and a helicopter-transportable 120 mm mortar. Each of these is extremely accurate. This accuracy is critical in counterinsurgency operations and irregular warfare, because accuracy reduces the instances of civilian casualties and collateral damage to local infrastructure.” This triple threat has become known as the triad of ground fires.
Lightweight 155 mm Towed Howitzer (M777)
Turning to the first critical triad of ground fires element, Conway explained, “The Lightweight 155 mm Towed Howitzer (M777) weighs about half of the cannon it is replacing and fires projectiles to a range of 15 to19 miles. Our Marine Expeditionary Brigade in Afghanistan has 15 of these howitzers at three different locations, which have collectively fired more than 600 rounds since April 2009.”
U.S. Marines with Kilo Battery, 3rd Battalion, 12th Marine Regiment (3/12) fire the M777 howitzer during an annual artillery relocation training fire mission at Yausubetsu training site in Hokkaido, Japan, Nov. 20, 2008. U.S. Marine Corps photo by Lance Cpl. Claudia M. Palacios.
The new “Triple Seven” fits perfectly within the Marine Corps’ “expeditionary” underpinnings. The system’s lighter weight, smaller footprint, and lower profile increase strategic deployability, tactical mobility, and survivability. The use of titanium in its major structures makes it 7,000 pounds lighter than its predecessor (the M198 towed 155 mm howitzer) with no sacrifice in range, stability, accuracy, or durability.
The M777A1 includes a new advanced digital fire control system called Towed Artillery Digitization (TAD). The M777A2 also includes the digital fire control system, but adds the capability to fire the XM982 “Excalibur” precision guided artillery projectile.
The program is jointly managed by both the Marine Corps and the Army, with the Marine Corps having the lead on the howitzer and the Army having the lead on the digital fire control system.
Today’s howitzer design builds upon earlier work performed by BAE Systems, which developed a “non-productionized” design that made extensive use of titanium to trim structural weight. The use of titanium in the design also increased system reliability by reducing the number of welds. As examples, both front and rear trails are now single piece castings, the saddle is just three castings welded together, and the bottom carriage is five castings welded together.
Early company explorations by BAE Systems were followed by the award of a 1997 U.S. research and development contract to the company, which eventually led to a 2002 low rate production contract award.
The Marine Corps began fielding the first of 511 new howitzers to the operating forces in April 2005 and expects to complete fielding in fiscal year 2011.
Two different versions of the M777 initially entered U.S. inventories: the M777A1 and M777A2.
The M777A1 includes a new advanced digital fire control system called Towed Artillery Digitization (TAD). The M777A2 also includes the digital fire control system, but adds the capability to fire the XM982 “Excalibur” precision guided artillery projectile.
In November 2009, members of the 3rd Battalion 11th Marine Regiment returned to their base in California after serving as the artillery support for Regimental Combat Team 3 in Helmand province, Afghanistan. Among their combat distinctions were being the first unit to conduct a combat helicopter lift to transport an M777A2 howitzer, and the first Marine Corps unit to fire the Excalibur.