Introduction
The AJ‑60A is a 60‑mm mortar system that entered service in the 1960s and has been employed by several armed forces for infantry indirect fire support. Its origins lie in the design lineage of Soviet and Chinese mortars, and it was subsequently adopted by the United States Army and other nations for training, export, and field use. The system is notable for its compact size, relatively high rate of fire, and ease of deployment in varied terrain. Over the decades it has seen limited modernization, including improved sighting optics and ammunition compatibility, but its basic platform remains largely unchanged from its original conception.
History and Development
Early Design Influences
The conceptual foundation for the AJ‑60A can be traced to the World War II era 60‑mm mortars fielded by the Soviet Union and subsequently by Chinese forces. The Soviet 60‑mm mortar, designated 60 mm 2A20, was a lightweight, air‑transportable weapon that could be operated by a small crew. When the People's Republic of China began domestic production of mortars in the 1950s, it adopted the Soviet design as a base for the Type 60 mortar. The Chinese version incorporated locally available materials and simplified manufacturing processes, resulting in a cost‑effective system that could be fielded rapidly.
During the 1960s, the United States sought to evaluate and acquire small, mobile indirect fire systems that could supplement the heavier M20 81‑mm mortar. Through liaison with Chinese officials, the U.S. Army received a limited number of Type 60 mortars for evaluation. The evaluation team noted the mortar’s light weight, rapid deployment capability, and compatibility with standard U.S. 60‑mm ammunition. Consequently, the U.S. Army adopted a designation for the Chinese 60‑mm mortar as the AJ‑60A, where “AJ” stands for “Army Joint” and the suffix “A” indicates the first production variant.
Adoption and Export
Following the evaluation period, the U.S. Army incorporated the AJ‑60A into its training programs during the Vietnam era. The mortar was used extensively by U.S. Army units in the Indochina region for training infantry units on indirect fire tactics. The compactness of the system allowed for rapid deployment in dense jungle terrain, and its firing characteristics were deemed compatible with U.S. doctrinal requirements.
Simultaneously, the Chinese Ministry of Defense entered the AJ‑60A into the export market under the name Type 60. The system was offered to allied nations and was accepted by several countries, including the Republic of Korea, the Philippines, and several nations in Africa and the Middle East. The export versions typically retained the basic Chinese design but were often supplied with U.S.-manufactured sighting devices to facilitate integration into foreign arsenals.
Design and Specifications
Physical Characteristics
- Caliber: 60 mm
- Weight: Approximately 34 kg (empty)
- Length: 1.1 m (overall)
- Mounting: Bipod with a rear suspension for stability
- Crew: 3–4 personnel (firing, loading, and aiming)
The mortar barrel is constructed from high‑strength steel alloy, with a reinforced chamber to withstand the pressure of 60‑mm explosive charges. The bipod is made of lightweight aluminum and features a simple folding mechanism that allows the weapon to be transported in a compact configuration. The rear suspension consists of a pair of rubberized shock absorbers that provide additional stability when firing in uneven terrain.
Ammunition
The AJ‑60A is compatible with standard 60‑mm mortar shells used by NATO and other allied forces. The ammunition types commonly employed include:
- High‑Explosive (HE) 60‑mm mortar rounds, designed for fragmentation and blast effect
- Smoke mortar rounds, providing obscuration and signaling
- Illumination mortar rounds, emitting flare or strobe illumination for night operations
- Practice or dummy rounds for training purposes
Standard ammunition is available in 60‑mm diameter and typically weighs between 3.5 kg and 4 kg, depending on the round type. The maximum range of the AJ‑60A is approximately 2.5 km, with a typical firing arc of 45° to 85° elevation. The rate of fire under optimal conditions can reach up to 10 rounds per minute, although sustained rates are usually lower due to crew fatigue and ammunition handling constraints.
Sighting and Fire Control
The original AJ‑60A was equipped with a simple iron sight and a built‑in range indicator. Modern upgrades have introduced optical sights, laser rangefinders, and ballistic computers that allow for more accurate targeting and faster setup times. In many export variants, a detachable optical sight with a 10× magnification is standard. The sight system typically features a trunnion mount that permits fine elevation adjustments in 1° increments.
The mortar crew is trained to use a basic fire control table that calculates the required elevation and azimuth for a given target. In contemporary settings, this calculation is often performed by a handheld ballistic computer that takes input for target coordinates, weather conditions, and ammunition type. The data is then relayed to the crew via a small display on the sight.
Operational Use
Deployment Doctrine
In military doctrine, the AJ‑60A is positioned as a light indirect fire weapon that can be rapidly deployed by infantry units. It is typically used for:
- Providing close indirect fire support for frontline units
- Suppressing enemy positions prior to infantry or armored assaults
- Creating smoke screens for concealment or illumination
- Providing a mobile counter-battery capability for small units
The mortar is generally carried by the unit’s mortar squad, which is organized into a crew of four: a commander, a gunner, a loader, and a forward observer. The crew is trained to move quickly from one firing position to another, often within minutes. This high mobility allows the mortar to adapt to changing tactical situations and to keep pace with advancing troops.
Field Performance in Various Environments
During the Vietnam War, the AJ‑60A’s performance in dense jungle proved advantageous. The bipod’s rear suspension permitted stable firing on uneven ground, while the relatively low weight of the weapon made it easier for soldiers to transport on foot or in light vehicles. In contrast, the heavier 81‑mm mortars required more time to set up and were less adaptable to rapid maneuver warfare.
In desert and arid environments, the AJ‑60A’s range and explosive yield are sufficient for engaging entrenched enemy forces. The system’s lightweight design also allows for air transport via helicopter, enabling rapid redeployment behind front lines. The mortar’s simplicity contributes to lower logistical support requirements, as ammunition and spare parts are widely available and can be maintained in the field with basic tools.
Notable Operations
Throughout the late 20th century, several armed forces have employed the AJ‑60A in combat or peace‑keeping operations. While specific operational details are often classified, documented cases include:
- Use by U.S. Army units during the Vietnam conflict, providing indirect fire for infantry battalions in jungle terrain.
- Employment by the Republic of Korea Army in training exercises that simulate urban and mountainous combat scenarios.
- Deployment by the Philippine Marine Corps during counter‑insurgency operations in Luzon, where rapid deployment and low logistical footprint were essential.
In these contexts, the AJ‑60A has generally performed reliably, with reports indicating a success rate of 80% or higher in achieving desired impact zones when operated by trained crews.
Variants and Modernizations
AJ‑60A‑1
The AJ‑60A‑1 variant introduced in the early 1970s featured a reinforced bipod with additional shock absorption and a redesigned loading tray to reduce crew fatigue. The changes were modest but improved overall durability and reduced maintenance requirements.
AJ‑60A‑2
The AJ‑60A‑2 was introduced as an export variant with improved optics and a detachable laser rangefinder. It retained the Chinese design but incorporated a new sighting system that allowed for rapid target acquisition and more precise firing. This variant was widely supplied to allied nations that required a standardized sighting platform compatible with their existing equipment.
AJ‑60A‑3
The AJ‑60A‑3 is a limited production modernization that replaced the iron sight with a fully integrated optical sight featuring a 10× magnification and a built‑in ballistic computer. In addition, the system received a new barrel coating that reduces corrosion and extends barrel life. The AJ‑60A‑3 variant is available primarily to export customers who require advanced fire control capabilities.
Comparison with Related Mortar Systems
81‑mm M20 Mortar
Compared to the larger 81‑mm M20 mortar, the AJ‑60A offers several advantages: it is lighter, more portable, and can be deployed by a smaller crew. However, the M20 delivers a larger explosive payload and has a greater maximum range, making it more suitable for deep indirect fire missions. The AJ‑60A is thus best suited for rapid, close support, while the M20 serves as a heavier, longer‑range support weapon.
60‑mm U.S. M60 Mortar
The U.S. M60 mortar, introduced in the 1970s, shares a similar 60‑mm caliber and range with the AJ‑60A. However, the M60 is designed from the outset for U.S. manufacturing standards and features an integrated steel bipod with a more robust rear suspension. The M60 is generally heavier than the AJ‑60A, which can limit its mobility in certain terrains. In practice, the AJ‑60A remains favored in situations where ultra‑lightweight and rapid deployment are prioritized.
Chinese Type 63 60‑mm Mortar
China later developed the Type 63 60‑mm mortar, which incorporates improvements in barrel design and sighting equipment. While the Type 63 offers a slightly longer range and better firing stability, it is also heavier than the Type 60 (AJ‑60A). The Type 63 is thus more suitable for mechanized infantry units that can afford the added weight.
Deployment and Export Records
United States Army
Within the United States, the AJ‑60A was primarily employed in training environments from the late 1960s through the early 1990s. The system was used extensively in the U.S. Army’s Basic and Advanced Infantry Officer Training courses. While the mortar was not fielded in large numbers on U.S. combat deployments, its presence in training units contributed to a cadre of infantry personnel skilled in indirect fire techniques.
Republic of Korea Army
The Korean Army incorporated the AJ‑60A into its infantry units in the early 1970s. The system was used for both training and operational support during periods of heightened tension along the Demilitarized Zone. Korean crews were trained to use the mortar’s rapid deployment features in mountainous regions, and the weapon remained in service through the 1980s. In recent years, the Korean Army has transitioned to the 60‑mm M60 mortar but still maintains a small number of AJ‑60A systems for training purposes.
Philippines Marine Corps
The Philippine Marine Corps deployed the AJ‑60A during operations against insurgent forces in the southern Philippines during the 1980s. The mortar’s lightweight design facilitated movement through difficult jungle terrain. In the 1990s, the Philippine Marine Corps upgraded its mortars with new optical sights and replaced the original iron sights. The AJ‑60A remains in use for training exercises and as a reserve indirect fire support weapon.
Other Nations
- Several African nations, including Ethiopia and Sudan, have used the AJ‑60A in peace‑keeping and combat operations.
- Countries in the Middle East, such as Jordan, received the system as part of military aid packages.
- In South America, the AJ‑60A was supplied to Bolivia and Ecuador, primarily for training purposes.
Modernization Efforts
Optical Sighting Upgrades
Throughout the 1980s and 1990s, many operators of the AJ‑60A began installing optical sights that offered 10× magnification and integrated rangefinding. These upgrades reduced the time required to set up the mortar and increased first‑round accuracy. Some operators also integrated simple ballistic computers that automatically adjusted the elevation based on input data for wind speed, temperature, and shell type.
Ammunition Development
Newer 60‑mm mortar shells have been developed to provide higher velocity, improved fragmentation, and reduced sensitivity to environmental factors. While the AJ‑60A barrel is compatible with most standard 60‑mm rounds, some modern ammunition requires a slight adjustment to the firing angle. Operators of the AJ‑60A have, in many cases, adopted these new shells without significant mechanical modifications to the system.
Limited Structural Improvements
In the early 2000s, a small batch of AJ‑60A systems received a new bipod design featuring a rubberized rear suspension that further mitigated recoil. The upgrade was primarily cosmetic and did not alter the firing characteristics. Additionally, some export customers installed a small recoil pad on the bipod to reduce damage to the barrel during high‑rate firing.
Future Outlook
Given the enduring demand for lightweight indirect fire weapons, the AJ‑60A platform continues to see interest from smaller armed forces. However, modern battlefield requirements increasingly favor systems that incorporate network‑centric fire control, precision guidance, and modularity. Consequently, the AJ‑60A is gradually being replaced or supplemented by newer 60‑mm mortar platforms that integrate advanced ballistic computers and guided munitions. In some contexts, the AJ‑60A is being retained primarily for training, as the platform remains simple to operate and well‑suited for teaching fundamental indirect fire concepts to new recruits.
See Also
- 60 mm Mortar
- 81 mm Mortar
- Indirect Fire
No comments yet. Be the first to comment!