Problems Persist, But Continuous Band Track Shows Promise in Light Armor Applications

The U. S. Army continuously seeks to reduce operating and support (O&S) costs for fielded combat systems while developing future combat systems that exhibit ultra high reliability with lower maintenance requirements. As the Army evolves from Army of Excellence (AOE) to Force XXI and beyond, we must achieve increases in force sustainability without sacrificing critical mobility, lethality, and survivability attributes. This remains a formidable task for legacy tracked combat systems, and will be a challenge for future systems unless we adopt changes in track design and materials. It has long been an accepted fact that tracked vehicles provide a stable weapons platform with excellent all-weather mobility over a wide range of terrain.1 However, the superior mobility of tracked platforms has traditionally incurred a substantial cost penalty. Historically, steel-tracked vehicles have higher O&S costs than wheeled combat platforms.2 The higher O&S costs are directly attributed to the rougher terrain profile characteristic of tracked vehicle employment (tracked vehicles endure a greater percentage of cross-country mileage than wheeled vehicles)3 as well as the maintenance burden imposed by their track and suspension systems. Furthermore, steel tracks inherently produce vibrations that adversely impact the reliability of onboard electronic components, contributing to even higher O&S costs. Continuous band track technology is not new and currently exists on Caterpillar 30/30 tractors, agriculture tractors (where soft soil mobility is critical), Small Unit Support Vehicles (like the Finnish SISU NA-140 all-terrain articulated vehicle) and Light Weight Trailers. The U. S. Army Tank-automotive and Armaments Command (TACOM) has awarded Caterpillar a contract option for producing the Deployable Universal Combat Earthmover (DEUCE) equipped with a continuous rubber track. Rubber track was selected to reduce Gross Vehicle Weight (GVW), thereby enhancing DEUCE deployability. The DEUCE can be parachuted into a combat zone and, thanks to its rubber tracks, can travel at speeds of up to 30 mph, permitting self-transport rather than truck/trailer transport.4 A rubber track system has also been developed, tested, and approved by the Canadian Department of National Defence for the Hägglunds BV206 vehicle, with test results indicating three times the life of the original Swedish-supplied track. Manufacturers, like Soucy International, claim continuous band tracks provide enhanced on/off road mobility through reduced ground pressure, better traction and lateral stability; reduced platform vibration, noise, radar/acoustic signatures, weight, and rolling resistance; improved track life; corrosion and maintenance-free operations; and lower life cycle costs.5 The U. S. Department of Defense and U. K. Ministry of Defense (MOD) have recently experimented with continuous band track on lightweight armor platforms. The continuous band track (commonly referred to as rubber track) is an endless, synthetic rubber molded track with internal drive system. The molded track is reinforced with Kevlar, nylon, polyester and/or glass fiber to provide rigidity and increased track life. Both the U. S. and U. K. are interested in determining the feasibility and military performance enhancements resulting from continuous band track on armored combat platforms. To verify the purported benefits of continuous band track, the U. S. Army evaluated an experimental band track on the M113A3 armored personnel carrier while the U. K. experimented with a similar track on a Combat Vehicle Reconnaissance (Tracked) (CVR(T)) platform. U. S. and U. K. test reports noted the following significant results:

• M113A3 paved surface rolling resistance for the band track was 67% less than the current T130 track. No significant difference was noted for operations in sand.6

• A 1,600-pound weight reduction was realized on the M113A3 equipped with band track as compared to the T130 track.7 On the CVR(T), the weight saving was 30%.

• M113A3 internal and external noise levels were 6 dB lower for the band track than for the T130 track.8

• The CVR(T) with band track achieved a 50% reduction in platform vibration.

• M113A3 band track durability (the point at which track separation occurs) was approximately 4,700 kms when tested over 20% primary (paved) roads, 40% secondary (gravel) roads and 40% cross-country at a 12 tons GVW.9

• Maintenance events for the M113A3 band track system included two drive sprocket replacements, two track throws (the same track was reinstalled), one idler wheel replacement, and three incidents where multiple wheel studs required tightening.10

Detail view of the continuous band track installed on an M113 APC during recent tests.

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Continuous Band Track (Continued from Page 21) 50 ARMOR — and reconnaissance missions while being entirely transparent to the enemy. This will dramatically increase its survivability and ability to fulfill its critical missions. Its predominant underlying operational philosophy should always remain: ‘The FSCS’s strength is in its stealth...’ The FSCS, as capable as it promises to be, must compete for availability of funds for R&D like any other major development program. The fully justified requirement to support the existing M1 series tank fleet until anew tank becomes available, while preserving the industrial base for armor design and production, will limit the allocation of funds set aside for the FSCS. The FSCS’s ultimate destiny, among other major development programs, was determined in the recent Army’s Quadrennial Defense Review (QDR) that will dictate the Army’s shape for the next 20-30 years. The proposed FSCS, with its powerful main armaments, alternative unique energy source to operate almost all systems, enhanced self-defense capabilities, digitized communications, computer networking ability, precision navigation and advanced aerial sensors, will be a paramount member of Army XXI and beyond. It has all the necessary ingredients to succeed.

Note: All information contained in this article was derived from open sources and the analysis of the authors.

Western Design HOWDEN (WDH) is a small defense company in Irvine, California, which specializes in the design, development and production of ammunition and material handling systems for the U. S. and International military markets. WDH’s track record includes a variety of air, land and seaborne weapon systems which require automated feed, resupply and optimized ammunition packaging. WDH has been involved among others in the Tank Test Bed, AC-130U Gunship, AH-64 Apache and Tank Compact Autoloader Programs.

Mr. Lawrence Bacon is the Director of Graphic Arts at WDH where, for the past 19 years, he has been responsible for creating numerous concepts for automatic ammunition handling, loading and storage systems.

Dr. Asher Sharoni, formerly the Director of Engineering with WDH, is the president of Howden Fluid Systems. He holds a Sc. D. in Mechanical Engineering from MIT and a M. Sc. and B. Sc. in Mechanical and Industrial Engineering from the Technion, Israel Institute of Technology. He is a former colonel in the Israeli Defense Forces, in which he was involved in various major armored weapons developments. Dr. Sharoni has accumulated more than 30 years of active experience in armor development, design, testing and production.

[Editorial Note: A. Sharoni and L. Bacon have co-authored the following other articles in ARMOR: The U. S. Future Main Battle Tank (FMBT); Autoloaders For Future Tanks; The Common Chassis Revisited: Should the Next Howitzer Be Built on the M1 Chassis?; Forward Area Air-Ground Defense For The Armored Forces-Revisited; and The Future Combat System (FCS).]