XM1203 non-line-of-sight cannon

{{Infobox Weapon

| name = XM1203 non-line-of-sight cannon

| image = File:XM1203 Non Line of Sight-Cannon (NLOS-C).jpg

|image_size=200

| caption = Prototype 1 of the NLOS-C in 2009

| origin = {{flag|United States}}

| type = Self-propelled artillery

| is_vehicle = yes

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| weight = 18+ tons

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| crew = 2

| armour = Composite

| primary_armament = 155 mm cannon

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| engine = Detroit Diesel 5L890

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The XM1203 non-line-of-sight cannon (NLOS-C) was a 155 mm self-propelled howitzer. It was the lead vehicle for the U.S. Army's Future Combat Systems Manned Ground Vehicles program.

The NLOS-C was a replacement for the M109 howitzer, but cancelled in December 2009. The NLOS-C used technology from the XM2001 Crusader, a U.S. Army self-propelled howitzer canceled in 2002.

The NLOS-C program was originally intended to provide networked, extended-range targeting, and precision attack of point and area targets in support of other combat units with a suite of munitions that included special purpose capabilities. The NLOS-C was intended to provide sustained fire for close support and destructive fire for tactical standoff engagement.

The NLOS-C was to provide responsive fire in support of the FCS combined arms battalions, and their subordinate units. It would have operated with line-of-sight, beyond-line-of-sight, non-line-of-sight (NLOS), external, and non-Army (joint warfare) capabilities.{{jargon inline|date=September 2021}}

File:NLOS-CAugust2003.jpg

The system, as proposed, looked to add capabilities that the M109 did not offer. One of the proposed systems advantages was the ability to switch shell types quickly on a one-by-one basis allowing an illumination round to be followed by a point-detonation round, to be followed by an area effect round. This would have given the system the ability to fire different rounds as required by different fire calls or to change types of shells. For instance, destroying a building then engaging anyone fleeing the area with the next round.

The rate of fire in the proposed system would have enabled more rounds to be fired in a given amount of time, allowing more firepower per system than available with the current M109 system. Another capability offered by the NLOS Cannon was multiple rounds simultaneous impact (MRSI) where the cannon fires a sequence of several rounds at different trajectories such that the rounds all hit the same target at the same time, resulting in little or no reaction time for the enemy to adjust its position. This was accomplished by including the autoloader from the Crusader project which achieved the goals of a much improved fire rate with a reduction in required crew.{{cite web |url=http://www.strategypage.com/htmw/htart/articles/20070724.aspx |title=M-109 Replacement Enters Production |publisher=Strategypage.com |date=2007-07-24 |access-date=2011-03-31 |archive-url=https://web.archive.org/web/20120118213251/http://www.strategypage.com/htmw/htart/articles/20070724.aspx |archive-date=2012-01-18 |url-status=live }}

The proposed system was envisioned as part of a fast mobile force networked via improved communications and data capabilities to allow rapid response with enhanced accuracy with the view to reducing friendly fire incidents along with lessened collateral damage, while providing superior protective artillery fire to units requiring gunfire support. Navigation of the vehicle and targeting information were provided via GPS and networked information systems.{{cite web |url=http://www.strategypage.com/htmw/htart/articles/20070724.aspx |title=Artillery: M-109 Replacement Enters Production |access-date=2009-07-06 |archive-url=https://web.archive.org/web/20090714041630/http://www.strategypage.com/htmw/htart/articles/20070724.aspx |archive-date=2009-07-14 |url-status=live }}

Improvements in the refueling arrangements and automation of ammunition reloading reduced the amount of time spent on resupply and during which the gun would be unavailable for combat support. This also allowed the system to use a crew of two instead of five.

The NLOS-C was among the heaviest of the eight MGV variants. In June 2003, the NLOS-C was projected to weigh 25.3 tons at essential combat capability and 29.2 tons at full combat capability.Pernin et al, Ch. 5, p. 95-118.

The NLOS-C had especially high commonality with the NLOS-Mortar vehicle.{{cite news |last1=Wasserbly |first1=Daniel |title=FCS Mortar System Moving Ahead in Wake of Its 'Big Brother' Cannon |url=https://www.jstor.org/stable/24826636 |access-date=18 February 2022 |work=Inside the Army |issue=16 |publisher=Inside Washington Publishers |date=21 April 2008 |volume=20 |page=FCS Mortar System Moving Ahead in Wake of Its 'big Brother' Cannon|jstor=24826636 }}