FCS 20-ton cannon in 2008 fact or fiction?

FCS 20-ton cannon in 2008 fact or fiction?

Charles J. Major Emerson

In the 1920s while reviewing the artillery developments of World War I, Lord Alanbrooke lamented the competing demands of artillery mobility and lethality. He drew upon the artillery lessons from the preceding war and the earlier Boer War: artillery had to be mobile enough to support transient targets and armored forces yet have enough firepower to destroy hardened targets. Britain was unsure of how to proceed with modernizing its forces. The chance for a new war on the European continent seemed remote amid the debate of how best to achieve artillery support. As a consequence, the modernization of artillery forces was allowed to languish, and the British were found to be ill-prepared at the start of World War II.

Today’s Army faces a similar period of modernization. We know the lessons of the past, and we have a vision for the future. The path to the vision is articulated in the Objective Force. The Objective Force White Paper dated 8 December 2002, and the Army’s Vision for 2020 are being realized through the future combat system (FCS) program. We cannot allow ourselves to be similarly complacent as the British were before World War II. Only by wavering in our commitment can we prevent success.

Originally described as a compilation of capabilities that were fulfilled through an array of systems, the FCS program has coalesced into a family of manned and unmanned vehicles joined through a comprehensive command, control, communications, computers, intelligence, surveillance and reconnaissance ([C.sup.4]ISR) network. With common mobility and survivability characteristics, the manned FCS variants will be 50 to 70 percent lighter than comparable systems in our inventory today yet exceed the collective capabilities of today’s warfighting systems and require a significantly smaller logistical tail.

The FCS cannon, one of the 20-ton class FCS family of vehicles, will provide responsive fires in support of combined arms battalions (CABs) and their subordinate units as part of the Objective Force. The FCS cannon used to be called the non-line-of-sight (NLOS) FCS. The first FCS cannon unit to be equipped is scheduled for 2008.

Is the FCS cannon a “Crusader replacement”? It is incorrect to assume that the FCS cannon is being developed solely as a response to the termination of Crusader. Indirect fires are a basic capability of the Objective Force, and thus, a platform that delivers them is integral to any plans for the development of the FCS family of systems.

However, Crusader’s termination did create a unique opportunity to initiate the development of the FCS cannon. With the funds freed up from Crusader’s termination, the Department of Defense ordered the Army to accelerate the development of several artillery modernization programs already in existence. Additionally, the Army was ordered to initiate an Objective Force indirect fire concept technology demonstration (CTD) and transfer relevant Crusader technology to the demonstration and other transformational programs. It is this CTD and transfer of Crusader technology that makes fielding the FCS cannon possible by 2008.

The CTD began 7 August 2002 and has two main objectives: Develop a materiel solution for the FCS cannon and develop technologies and common materiel solutions for use by the FCS cannon and the entire family of FCS manned ground vehicles.

The ambitiously low-weight goal of the FCS family of systems brings up a question essential to the development of the Objective Force indirect fire capability. Can a modern automated artillery piece (FCS cannon) be created under 20-tons? And what use can the technologies matured under Crusader (itself a 40-ton platform) provide a system that must be under 20-tons to achieve the deployability standard of the Objective Force?

The weight of a combat vehicle is in large measure determined by the mission it is designed to perform. Other factors, such as crew size, volume under armor and means of protection also play a role. In short, the FCS cannon is a very different vehicle than Crusader and represents the capability of the latest technologies combined with a ruthless examination of FCS cannon requirements, requirements that reflect how the FCS cannon will fight. (See the figure on Page 26.)

How will the FCS cannon fight? The FCS cannon will allow options to fight in fundamentally different ways than today’s artillery systems. Networked fires enable these options. Rather than a centralized pathway for fires requests with many decision points, the operations of the FCS cannon will be characterized by multiple direct links from individual sensors to FCS cannons or pairs of FCS cannons. These decentralized communications pathways will greatly increase responsiveness to calls-for-fires.

FCS cannons will operate in close proximity to maneuver forces rather than in their own platoon and battery position areas. Because FCS cannons will have common mobility with the other FCS variants (50 kilometers per hour cross-country), they will execute mobility battle drills normally the province of maneuver forces. This will increase the FCS cannons’ survivability and allow them to support the CABs better.

Because the FCS cannons will be able to resupply/rearm at a much greater speed, resupply will occur during battle lulls rather than as part of a longer tactical move. Additionally resupply will be in the vicinity of the cannon rather than in a resupply area to the rear.

In the Objective Force fires will support maneuver, but the converse is also true: maneuver will support fires. The seamless transitions of shifting support from one to the other during operations will put unrelenting pressure on the enemy. The goal will be to create multiple dilemmas for the enemy commander.

A typical combat day for the FCS cannon would call for a mix of its capabilities: a large burst of fire missions interspersed with rapid resupply in position immediately followed by a long tactical maneuver. Cannon crewman will be much more battle-focused than today’s artillerymen.

What Crusader technologies are relevant? Not all technologies slated to be used for a 40-ton platform apply to the development of a 20-ton cannon on a FCS chassis common to a family of vehicles. But many do.

Ammunition Handling System. This system was at the heart of Crusader’s ability to provide responsive fires. Consisting of storage magazines, robotic transfer equipment and the software control routines to use them, the ammunition handling system is required if the FCS cannon is to achieve rates-of-fire similar to Crusader. Reliable and comparatively lightweight for its capabilities, the ammunition handling system will be incorporated into the FCS cannon with some minimum changes due to differences in platform layout and resupply methods.

In conjunction with a weight optimized cannon tube, this system will allow the FCS cannon to achieve a rate-of-fire of six to ten rounds per minute that is equal to or better than the best systems in the world today and will be able to maintain that rate-of-fire for the duration of the engagement. The effect of this integration of automated ammunition handling and cannon technologies means that fires will be impacting exactly where needed “on-demand” throughout the battle.

Projectile Tracking System (PTS). PTS is a method for dramatically improving the accuracy of munitions fired from the cannon. Consisting of a narrow beam radar and detector, it tracks projectiles and compares “should hit” to “did hit” target location before the round completes its trajectory. With this information, the cannon continually adjusts the firing solution to achieve an optimum aim point in every firing mission. This adjustment occurs round to round and dramatically improves the efficacy of the cannon’s fires.

When combined with improved sensors for targeting and modem munitions, PTS will ensure precision effects even at the extreme edge of the cannon’s range. PTS is a mature technology that does not add significantly to the weight of the cannon.

Resupply. One of the major concerns of any artillery piece is the amount of time it takes to resupply. Throughout the world, all artillery pieces are resupplied by hand in a time-consuming, manpower-intensive exercise.

In the US, a Paladin crew loads its howitzer at the rate of a round per minute, making a standard resupply last the bulk of an hour. This “man-in-the-loop” aspect of resupply vastly increases the time it takes to resupply when the conditions are less than ideal: at night, while wearing mission-oriented protective posture (MOPP) gear or in extreme cold weather gear or wet/icy conditions.

Crusader would have used a dedicated resupply vehicle that quickly and automatically rearmed the howitzer through an armored boom. Feeding the vehicle one round at a time, the crew would have remained safe under armor yet could have disengaged the resupply operation in seconds if threatened.

Because of the extensive ammunition handling and storage requirements unique to the vehicle being rearmed, this method of resupply would not be feasible for the FCS cannon or other variants in the ECS family of systems. Instead, the FCS cannon will feature a resupply mechanism using preloaded magazines to quickly bring a cannon with depleted stocks back to its full load.

This ammunition magazine is envisioned to be common across the family of FCS vehicles. Line-of-sight (LOS), beyond-line-of-sight (BLOS) and mortars will use the same magazines with ammunition specific to each vehicle.

The FCS cannon will be able to completely rearm in less than 12 minutes. Additionally, it will do this through automation with fewer soldiers who are protected inside their respective systems. Resupply of fuel and water will be similarly automated, potentially in conjunction with rearming ammunition. These resupply systems will be similar to those used across the FCS family of systems, drastically reducing the load on the logistical chain.

The FCS cannon will not have a unique resupply vehicle dedicated to its support. The FCS program is coordinating with Training and Doctrine Command (TRADOC) proponents and industry to create the requirements for a future tactical truck system (FTTS) that will be a resupply vehicle common throughout the FCS-equipped force.

Crew Cockpit. Crusader spent much of its effort on optimizing the interfaces and operating areas of the crew. This resulted in a cockpit for the crew that facilitated the tactical employment of the howitzer in sustained operations. The abilities of the cockpit are largely independent of the type of ground combat vehicle it is located in; so this technology is ripe for transfer across the FCS variants.

The FCS cannon will be enabled by advances in the application of fires. Integrated into the battlefield command system (BCS software, networked fires will exploit technological advances and combine them with new concepts in controlling fires. This will enable the force to link a target with a shooter in real-time, dynamically adjust fires allocations, and assess and reassess target status and damage while reducing the chances of fratricide or collateral damage. The results of networked fires will be the best pairing of effects and targets at the right time in support of the commander.

Survivability. The force that Crusader was originally envisioned to support is substantially different than the Objective Force. In order to pace Abrams tanks and Bradley fighting vehicles, Crusader used similar armored packages to achieve a comparable level of protection.

The light and deployable FCS systems preclude the kind of “brute force” armor approach that Crusader incorporated. Nevertheless, several of the advanced materials and capabilities integrated into the Crusader late in the program to achieve a 40-ton deployability weight are likely to be included in FCS. These advanced capabilities will play a big part in the FCS family of vehicles’ achieving C-130 deployability and remaining survivable.

Additionally, the layout of the FCS cannon will be significantly smaller than Crusader. This reduces the internal volume and the requirement for heavy protective armor. These and other technological advances are at the core of achieving a platform weight of under 20 tons.

Despite the lesser weight, incorporating the latest survivability advances makes the FCS cannon more survivable than the 40-ton Crusader. Giving up weight does not mean giving up protection.

Other Technologies. Several other technologies matured under the Crusader program will migrate into FCS. These include the laser ignition system for the propellant, embedded training, drive-by-wire technologies and a real-time common operating system for the manned ground vehicle system.

Because Crusader was the first major ground vehicle that featured all-electric drive assemblies (as opposed to using hydraulics like other ground vehicles), FCS will benefit from power generation and control systems that were optimized for Crusader.

Manufacturing large titanium assemblies is an extremely difficult process, but that capability was matured under the Crusader program. FCS is expected to use several titanium assemblies and will benefit from this maturity.

Crusader’s band track, a one-piece reinforced rubber track, has great potential for use in the FCS family of vehicles. Potentially, it will make vehicles lighter than comparative wheeled systems.

Additionally, several of the development systems and procedures (practices, software tools, simulations, virtual environments) that were in place for the Crusader program are being used in the development of FCS.

The impact of these Crusader technologies on the development of the FCS cannon cannot be overstated. Because the design team has all the tools at hand, they can develop the FCS cannon on the shortened timeline.

What characteristics will FCS cannon have in common with the FCS family of systems? In many ways, the operation of the FCS cannon will resemble the operations of all other FCS manned ground vehicles. Common features across the FCS family of systems will include access to the BCS; planning, training and communications software; maintenance parts and procedures; water generation; common resupply implementation; and other capabilities.

Using a common chassis, the FCS cannon will have the advanced mobility and survivability of the FCS. The chassis will boast a suspension capable of smoothly traversing rough terrain at speeds of greater than 50 kilometers per hour. For the first time in recent history, the cannon will enjoy the same mobility as the supported force.

The common chassis will feature reduced fuel consumption. Through a combination of engine and hybrid electric advancements, the FCS will be able to travel hundreds of kilometers on its on-board fuel capacity.

The commonality of the manned ground vehicles combined with the automation of the resupply functions for ammunition and fuel will enable the FCS to have a significantly smaller supply tail.

What will the FCS cannon’s caliber be? Currently, there are a number of analyses and experiments being conducted in support of the Objective Force development. The initial analyses for the CTD demonstrated that both 105-mm and 155-mm caliber systems are feasible designs for the FCS cannon. Additionally, the mobility system could be tracked or wheeled. The CTD will culminate in a firing demonstrator, and the Field Artillery Center, Fort Sill, Oklahoma, has recommended the demonstrator be a 155-mm band-tracked vehicle.

This does not mean that, that is the final decision on caliber or chassis design. The final decision rests on analyses due to be completed later this year and on the best overall technical approach to achieve the FCS.

The 20-ton FCS cannon will provide the Army a strategically deployable, tactically mobile, networked, responsive, precision strike NLOS weapons platform to deal with the uncertainties of future battlefields. Given the requirements of the system and the maturity of technologies at hand, it is a fact that the FCS cannon can be fielded in 2008.


Maximum Range: 30 to 40 kilometers

Minimum Range: 3 to 4 kilometers

Rate-of-Fire: 6 to 10 Rounds per Minute

Caliber: Undefined

Resupply: Complete in 5 to 12 Minutes

Payload: 24 to 48 Rounds

Munitions: All Current and Developmental Munitions of its Caliber

Responsiveness: Emplaced within 15 to 20 Seconds and Moving 20 to 30 Seconds

Cross-Country Speed: Greater than 50 Miles Per Hour

Deployability: C-130 Aircraft

Deployable on C-130 with FCS cannon, crew, equipment, three-quarters of a tank of fuel and a fighting load of ammunition and be capable of self defense upon arrival. The FCS cannon will have a basic armor package, but the optional armor package is not included in this requirement.

Future Combat System (FCS) Cannon Requirement

Major Charles J. (Jack) Emerson, Jr., Acquisition Corps (AC), is a Combat Developer Staff Officer in the Training and Doctrine Command (TRADOC) Systems Manager for Cannons (TSM Cannon), Fort Sill, Oklahoma. In his previous assignment, he was the Combat Developer In-Plant Representative to the prime contractor for Crusader, United Defense Limited Partnership, Minneapolis, Minnesota. Among other assignments, he served as Commander of Service Battery in the 1st Battalion, 82d Field Artillery, 1st Cavalry Division, Fort Hood, Texas; Assistant Fire Support Coordinator (AFSCOORD) for the Division, also in the 1st Cavalry Division; and Platoon Leader in the 5th Battalion, 17th Field Artillery, 210th Field Artillery Brigade, VII Corps, Germany. He also has served as a Test Officer for the US Army Operational Test Command at Fort Hood.

COPYRIGHT 2003 U.S. Field Artillery Association

COPYRIGHT 2004 Gale Group