The Historical Combat Effectiveness of Lighter-Weight Armored Forces

In 2001, The Dupuy Institute conducted a study for the U.S. Army Center for Army Analysis (CAA) on the historical effectiveness of lighter-weight armored forces. At the time, the Army had developed a requirement for an Interim Armored Vehicle (IAV), lighter and more deployable than existing M1 Abrams Main Battle Tank and the M2 Bradley Infantry Fighting Vehicle, to form the backbone of the future “Objective Force.” This program would result in development of the Stryker Infantry Fighting Vehicle.

CAA initiated the TDI study at the request of Walter W. “Don” Hollis, then the Deputy Undersecretary of the Army for Operations Research (a position that was eliminated in 2006.) TDI completed and submitted “The Historical Combat Effectiveness of Lighter-Weight Armored Forces” to CAA in August 2001. It examined the effectiveness of light and medium-weight armored forces in six scenarios:

• Conventional conflicts against an armor supported or armor heavy force.
• Emergency insertions against an armor supported or armor heavy force.
• Conventional conflict against a primarily infantry force (as one might encounter in sub-Saharan Africa).
• Emergency insertion against a primarily infantry force.
• A small to medium insurgency (includes an insurgency that develops during a peacekeeping operation).
• A peacekeeping operation or similar Operation Other Than War (OOTW) that has some potential for violence.

The historical data the study drew upon came from 146 cases of small-scale contingency operations; U.S. involvement in Vietnam; German counterinsurgency operations in the Balkans, 1941-1945; the Philippines Campaign, 1941-42; the Normandy Campaign, 1944; the Korean War 1950-51; the Persian Gulf War, 1990-91; and U.S. and European experiences with light and medium-weight armor in World War II.

The major conclusions of the study were:

Small Scale Contingency Operations (SSCOs)

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. It would appear that existing systems (M-2 and M-3 Bradley and M-113) can fulfill most requirements. Current plans to develop an advanced LAV-type vehicle may cover almost all other shortfalls. Mine protection is a design feature that should be emphasized.
2. Implications for the Interim Brigade Combat Team (IBCT). The need for armor in SSCOs that are not conventional or closely conventional in nature is limited and rarely approaches the requirements of a brigade-size armored force.

Insurgencies

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. It would appear that existing systems (M-2 and M-3 Bradley and M-113) can fulfill most requirements. The armor threat in insurgencies is very limited until the later stages if the conflict transitions to conventional war. In either case, mine protection is a design feature that may be critical.
2. Implications for the Interim Brigade Combat Team (IBCT). It is the nature of insurgencies that rapid deployment of armor is not essential. The armor threat in insurgencies is very limited until the later stages if the conflict transitions to a conventional war and rarely approaches the requirements of a brigade-size armored force.

Conventional Warfare

Conventional Conflict Against An Armor Supported Or Armor Heavy Force

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. It may be expected that opposing heavy armor in a conventional armor versus armor engagement could significantly overmatch the IAV. In this case the primary requirement would be for a weapon system that would allow the IAV to defeat the enemy armor before it could engage the IAV.
2. Implications for the Interim Brigade Combat Team (IBCT). The IBCT could substitute as an armored cavalry force in such a scenario.

Conventional Conflict Against A Primarily Infantry Force

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. This appears to be little different from those conclusions found for the use of armor in SSCOs and Insurgencies.
2. Implications for the Interim Brigade Combat Team (IBCT). The lack of a major armor threat will make the presence of armor useful.

Emergency Insertion Against An Armor Supported Or Armor Heavy Force

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. It appears that the IAV may be of great use in an emergency insertion. However, the caveat regarding the threat of being overmatched by conventional heavy armor mentioned above should not be ignored. In this case the primary requirement would be for a weapon system that would allow the IAV to defeat the enemy armor before it could engage the IAV.
2. Implications for the Interim Brigade Combat Team (IBCT). Although the theoretical utility of the IBCT in this scenario may be great it should be noted that The Dupuy Institute was only able to find one comparable case of such a deployment which resulted in actual conflict in US military history in the last 60 years (Korea, 1950). In this case the effect of pushing forward light tanks into the face of heavier enemy tanks was marginal.

Emergency Insertion Against A Primarily Infantry Force

1. Implications for the Interim Armored Vehicle (IAV) Family of Vehicles. The lack of a major armor threat in this scenario will make the presence of any armor useful. However, The Dupuy Institute was unable to identify the existence of any such cases in the historical record.
2. Implications for the Interim Brigade Combat Team (IBCT). The lack of a major armor threat will make the presence of any armor useful. However, The Dupuy Institute was unable to identify the existence of any such cases in the historical record.

Other Conclusions

Wheeled Vehicles

1. There is little historical evidence one way or the other establishing whether wheels or tracks are the preferable feature of AFVs.

Vehicle Design

1. In SSCOs access to a large-caliber main gun was useful for demolishing obstacles and buildings. This capability is not unique and could be replaced by AT missiles armed CFVs, IFVs and APCs.
2. Any new lighter tank-like vehicle should make its gun system the highest priority, armor secondary and mobility and maneuverability tertiary.
3. Mine protection should be emphasized. Mines were a major threat to all types of armor in many scenarios. In many SSCOs it was the major cause of armored vehicle losses.
4. The robust carrying capacity offered by an APC over a tank is an advantage during many SSCOs.

Terrain Issues

1. The use of armor in urban fighting, even in SSCOs, is still limited. The threat to armor from other armor in urban terrain during SSCOs is almost nonexistent. Most urban warfare armor needs, where armor basically serves as a support weapon, can be met with light armor (CFVs, IFVs, and APCs).
2. Vehicle weight is sometimes a limiting factor in less developed areas. In all cases where this was a problem, there was not a corresponding armor threat. As such, in almost all cases, the missions and tasks of a tank can be fulfilled with other light armor (CFVs, IFVs, or APCs).
3. The primary terrain problem is rivers and flooded areas. It would appear that in difficult terrain, especially heavily forested terrain (areas with lots of rainfall, like jungles), a robust river crossing capability is required.

Operational Factors

1. Emergency insertions and delaying actions sometimes appear to be a good way to lose lots of armor for limited gain. This tends to come about due to terrain problems, enemy infiltration and bypassing, and the general confusion prevalent in such operations. The Army should be careful not to piecemeal assets when inserting valuable armor resources into a ‘hot’ situation. In many cases holding back and massing the armor for defense or counter-attack may be the better option.
2. Transportability limitations have not been a major factor in the past for determining whether lighter or heavier armor were sent into a SSCO or a combat environment.

Casualty Sensitivity

1. In a SSCO or insurgency, in most cases the weight and armor of the AFVs is not critical. As such, one would not expect any significant changes in losses regardless of the type of AFV used (MBT, medium-weight armor, or light armor). However, the perception that US forces are not equipped with the best-protected vehicle may cause some domestic political problems. The US government is very casualty sensitive during SSCOs. Furthermore, the current US main battle tank particularly impressive, and may help provide some additional intimidation in SSCOs.
2. In any emergency insertion scenario or conventional war scenario, the use of lighter armor could result in higher US casualties and lesser combat effectiveness. This will certainly cause some domestic political problems and may impact army morale. However by the same token, light infantry forces, unsupported by easily deployable armor could present a worse situation.