JULY 2009

Expeditionary Fire Support System

Version Two

by Maj Brian P. Duplessis

No recent ground weapons system has stirred as much debate as the expeditionary fire support system (EFSS). Since 2000 the Gazette has seen numerous articles advocating weapons type, assignment within the ground combat element, and the validity of the EFSS requirement itself. EFSS, in initial form, is an M327 120mm rifled towed (RT) mortar. EFSS should, however, progress to an ultralightweight, fully digitized 105mm pack howitzer (ULWPH), firing advanced ammunition and capable of limited self-propelled mobility via an auxiliary power unit (APU).

EFSS: A Niche Weapon

EFSS, in current form, is a niche weapon intended to support the vertical assault element of a ship-to-objective maneuver force for up to 72 hours.1 Within those 72 hours, vehicles and howitzers are expected to come ashore and link up with their respective firing units whereupon artillery swaps mortars for cannon in order to support subsequent operations ashore. This requirement to embark two distinct unit sets of equipment raises logistics concerns that have not been previously addressed in professional journals. An M777A2 artillery battery is anchored to a sizeable logistics footprint. The addition of EFSS battery equipment further inflates this already critical mass. This requirement for additional deck space is also counterintuitive to requirements set forth in Expeditionary Fire Support: The System After Next. Furthermore, the diversion of assault support sorties to recover EFSS equipment following the transition to cannon has not been addressed either. We have accepted this inefficiency due to the requirement for an EFSS section2 to be internally transportable by two MV–22 sorties.3

The M327 maximum rate of fire, four rounds per minute,4 doesn’t match that of most howitzers, much less mortars. While EFSS offers value in terms of portability, it suffers from the inherent disadvantages of mortars when compared to howitzers. The principal disadvantage is range; maximum unassisted range is less than one-third that of the M777A2. Emplacement is more challenging in terms of labor and suitable terrain due to the requirement to seat the baseplate. Mortars are limited to high-angle fire only, rendering EFSS incapable of direct fire in defense of the firing unit or the precise engagement of point targets.5 Lastly, high-angle fire is the least preferred method of engagement when required to deconflict indirect fire weapons trajectories and aircraft flight paths, an enduring requirement in the conduct of vertical assault operations.

EFSS: Version Two

A proposed solution to the shortcomings of the M327 120mm RT mortar is to adopt a 105mm ULWPH, firing advanced ammunition and equipped with an APU as a source of propulsion. This EFSS replacement would serve as the Corps’ primary close support weapon, supplanting a number of M777A2s in service.

105mm ULWPH. The M327 120mm RT mortar should be replaced by a 105mm ULWPH weighing less than 3,000 pounds and capable of assembly or disassembly in 4 minutes or less. Each component should weigh less than 300 pounds, facilitating movement by pack animal, sled, cart or, for short distances only, via manual lift. The ability to rapidly and efficiently assemble and disassemble the weapon facilitates internal transport in a wide variety of helicopters, unlike other 105mm variants that require internal shoring of the aircraft cabin in order to accommodate the weapon’s weight.

ULWPH should be fully digitized with an onboard system similar to the M777A2’s digital fire control system (DFCS). The ULWPH DFCS should be self-locating and self-laying, capable of onboard technical firing data computation, equipped with an integral muzzle velocity system, and able to digitally receive calls for fire via sensor-to-shooter communications. A platform integration kit should be incorporated to fire 105mm precision guided munitions as they are developed and enter service. Table 1 (see p. 56) depicts ULWPH performance parameters.

While these specifications may seem optimistic, they have precedence. In 1956 Oto Melara of Italy introduced the 105mm Type 56 pack howitzer, which subsequently saw service with 22 nations; 15 of these nations continue to employ this unique weapon. The Type 56 is a 2,840-pound, 14 caliber, 105mm pack howitzer capable of rapid disassembly into 14 subcomponents, none weighing more than 268 pounds. The Type 56 achieves 10,560 meters unassisted range and 13,000 meters assisted range. Given advances in engineering, weapons design, and metallurgy, particularly the use of titanium alloys, it is not unreasonable to assume that a similar weapon with improved durability and performance can be produced. The currently available 3,300-pound, 19,500 meter assisted range Giat LG1 MK II 105mm howitzer and the M777A2, a 9,000-pound 155mm howitzer, both support this assumption.

Advanced cannon artillery ammunition program (ACAAP). Advances in 105mm ammunition have resulted in 155mm lethality in 105mm projectiles against personnel and light material target types, the primary target set for artillery. Additionally, advanced 105mm ammunition addresses the primary inefficiency of the current artillery ammunition suite—too many projectile families. In order to correct this shortcoming, General Dynamics Ordnance and Tactical Systems, in cooperation with Denel of South Africa, has produced a revolutionary suite of ballistically matched 105mm and 155mm projectiles. In addition to ballistic similitude, these projectiles offer the flexibility of field interchangeable boat tail or base bleed units, thereby simplifying logistical planning and offering maximum flexibility to artillery commanders and supported units alike.6 Additionally, all variants employ insensitive munitions fillers, reducing susceptibility to fire and explosions. All projectiles are compliant with the NATO Joint Ballistic Memorandum of Understanding, thereby maintaining interoperability with allies.7 A brief discussion of the 105mm suite follows. Specific munitions include the following:8

• M0125 insensitive high-explosive preformed fragmentation (HE PFF).
• M0203 insensitive munitions (IM) HE.
• M2019 HE or practice inert (PI).
• M0109 velocity-enhanced long-range artillery projectile (V-LAP) IM HE PFF (developmental).
• M0101 bispectral screening smoke.
• M0102 illumination (Ill).
• M0235 infrared (IR) Ill.

Table 2 (see p. 56) compares the current suite of 105mm munitions with the 105mm ACAAP suite.

105mm ACAAP achieves 155mm lethality against personnel-type targets through the use of PFF. 105mm PFF rounds feature 7,800 tungsten pellets packed within a prescored shell body.9 These tungsten pellets are devastating against personnel and light material. The prescored body also regulates the size and dispersion of shell fragmentation, lessening the probabilities of collateral damage. Figure 1 graphically depicts the arrays of tungsten pellets within a 105mm PFF projectile. 105mm PFF possesses higher lethality values and coverage area than the current use M107 155mm HE projectile.10 Figures 2 through 5 graphically display the effectiveness of 105mm ACAAP ammunition against personnel-type targets. The Marine Corps does not have an interest in these munitions because of its lack of 105mm weaponry. The U.S. Army is testing and evaluating this ammunition for future use.11

Precision guidance kit (PGK). The PGK does for the artillery round what the joint direct attack munition kit does for “dumb” bombs. The chief element of the PGK is a course-correcting fuse that responds to satellite signals and deploys brakes to correct the course of the projectile during flight causing it to impact within 50 meters of the target.12 The PGK is particularly critical for deep fires due to the inherent loss of accuracy at longer ranges.13 Figure 6 graphically depicts the operation of a PGK.

APU. One of the requirements for EFSS is the ability to transport the weapon, prime mover, and a portion of its crew and ammo in two MV–22 sorties.14 No current 105mm howitzer and vehicle prime mover combination can meet these specifications. An unexplored alternative is to equip ULWPH with an APU to serve as a partially self-propelled platform.

The performance specifications for EFSS state that the system is to have mobility equal to or greater than the supported unit.15 An APU propelling ULWPH at speeds of 4 to 6 miles per hour cross-country and 6 to 10 miles per hour on roads would provide sufficient mobility to support foot-mobile infantry. Such APUs exist. A 76 horsepower APU propels the 27,000-pound Denel G5 155mm howitzer to speeds of 10 miles per hour on roads and 2 miles per hour cross-country.16 Another example is the Russian SD44 85mm antitank gun, propelled by a 14 horsepower APU and capable of 151/2 miles per hour road speed. Based on these examples, it is reasonable to assume a lightweight 35 to 50 horsepower APU could propel a 3,000- to 4,000-pound weapon to the speeds specified above. Due to ULWPH’s vastly superior range, compared to a 120mm mortar, its movement requirements will generally be limited to short-range survivability moves.17

Conclusion

The artillery community should divest the M327. It is a niche weapon with limited flexibility for service in a direct support artillery role. The past is prologue as the Corps has previously, and unsuccessfully, attempted to employ heavy mortars as direct support artillery.18 The Army relearned this hard lesson early on in Afghanistan inspiring the enduring deployment of field artillery to that theater.19 One option is to pass EFSS to the infantry who could maintain it in the same fashion as the U.S. Army Rangers maintain three types of mortars (60mm, 81mm, and 120mm) employing a mission-oriented mix of weaponry.20 As another employment option, infantry battalions could drop to six weapons in each 81mm mortar platoon and use the manpower savings to stand up a regimental 120mm mortar battery, giving the infantry regiment an organic heavy and medium mortar tube inventory of eighteen 81mm and six 120mm mortars vice twenty-four 81mm mortars.

In order to assume the EFSS role, in addition to serving as the Corps’ principal close fires platform, ULWPH should be adopted. The Marine Corps originally discarded its 105mm weapons due to lack of range and lethality in addition to the Corps’ quest to achieve efficiency through the use of a single caliber for artillery weaponry.21 These viewpoints are no longer valid.
Due to advances in ammunition and weapon design, modern 105mm weapons boast range and lethality nearly equal to and in some cases exceeding the performance of 155mm systems. Lastly, with regard to logistics efficiency, by adopting a 120mm mortar the Corps has already introduced another caliber of ammunition. With some creativity and innovation, ULWPH can fulfill both the EFSS and primary close fires requirements.

While the maximum potential range of ULWPH does not meet that of the M777A2, it is adequate for the close fires requirement. For example, 54 percent of 19,983 artillery rounds expended by 11th Marine Regiment in Operation IRAQI FREEDOM I (OIF I) were fired at ranges less than or equal to 18.1 kilometers, well within the range envelope of ULWPH.22 Furthermore, the majority of deep fires in OIF I were counterfire missions or counterbattery programs of fire. ULWPH’s small footprint and tactical agility facilitate positioning closer to the supported unit, thereby expanding the range fan.

ULWPH should be a one-for-one replacement for most M777A2s. These displaced systems can be provided to allies, the Reserves, and/or sold through foreign military sales. The remaining M777A2s should be employed as general support weapons.

Notes

1. Lewis, Maj James C., “Brief to Field Artillery Association” presentation, Quantico, 6 November 2006.

2. An EFSS system consists of one M327 120mm RT mortar, a trailer, and two internally transportable vehicles—one to tow the weapon and one to tow the trailer with 24 rounds of ammunition.

3. Lewis.

4. United States Government Accountability Office, Defense Acquisitions: Status of the Safety, Performance, and Reliability of the Expeditionary Fire Support System, Washington, DC, 18 November 2008.

5. Cook, Maj Samuel C., “Why EFSS Shouldn’t Be a One-Trick Pony,” Marine Corps Gazette, November 2002, p. 85.

6. General Dynamics Ordnance and Tactical Systems, Response to Sources Sought Notice W15QKN–06–X–0866 for 155mm Artillery Projectile Suite, Saint Petersburg, FL, 30 April 2006.

7. Ibid.

8. General Dynamics Ordnance and Tactical Systems, Response to Sources Sought Notice W15QKN–06–X–0865 for 105mm Artillery Projectile Suite, 30 April 2006.

9. Ibid.

10. Ibid.

11. Rogers, LtCol Kevin C., USMC(Ret), “Trip Report: Site Visit to Denel Ammunition Facilities, South Africa, 14–26 January 2005,” Fort Sill, OK, 2 February 2005.

12. Moorhead, Maj John S., “Precision Guidance Kits (PGKs): Improving the Accuracy of Conventional Cannon Rounds,” Field Artillery, Fort Sill, OK, January 2007, p. 31.

13. Ibid.

14. Lewis.

15. Bohaner, Donald H., “Expeditionary Fire Support System,” available at http://usmilitary.
about.com/od/marineweapons/ a/efss.htm, accessed 28 November 2006.

16. GlobalSecurity.org, “G5 155mm 45-calibre, towed gun howitzer,” available at http://www.
globalsecurity.org/military/world/rsa/g5-specs.htm, accessed 17 December 2006.

17. Mitchell, Capt Joshua A., “A Case for Howitzers in Afghanistan.” Field Artillery, Fort Sill, OK, June 2003, p. 7.

18. Parry, Col Francis F., USMC(Ret),Three War Marine, Pacifica Press, Pacifica, CA, 1987.

19. Mitchell, pp. 6–9.

20. Ibid., p. 7.

21. Palm, MajGen Leslie M., USMC(Ret), “Marine Artillery’s Dilemma: The Requirements-Acquisition Disconnect,” Marine Corps Gazette, February 2003, p. 37.

22. Gentry, LtCol Keil R., “The Aftermath: Killing Munitions” presentation, location unknown, modified 3 June 2003.

Additional Resources

"Why EFSS Shouldn 't Be a One-Trick Pony: How the 105mm howitzer is superior to the 120mm mortar." By Maj Samuel C. Cook; Marine Corps Gazette,November 2004.