M113A1 ACAV in 1/35...
...another new kit coming from AFV Club
News of another new kit planned from AFV Club this year and it is a return to the subject of the Vietnam War, the M113 ACAV ((Armoured Cavalry Assault Vehhicle). AFV Club have some photos of a test build and they have been kind enough to share them with us. They also have a set of notes to go with the kit:-
AF35113 - M113 ACAV
Actual combat experience verified that the mainstream open-top semi-track armoured personnel carriers during World War II cannot fulfill the needs of infantry in joint combat operations with fighting vehicles. Before the war ended, the US army began to develop fully tracked and enclosed armoured personnel carrier by using existing fighting vehicle’s power and suspension system.
During this period, components form M24 and M18 were used for development of new APC capable of carrying 18 to 27 crews. However, the projects were terminated due to unsatisfied engine performance, over-size or over-weight bodies.
After the war, the US army doctrine considered that the organization of an infantry squad is better to reduce from 12 to 10 soldiers. At the same time, the relatively lightweight and air transportable M75 APC was introduced in 1952. M75 with same engine and tracks as M41 light tank was fielded in the late period of Korean War. The driver of M75 sits in the front left of the hull, with the engine to his right. In the center of the vehicle sits the commander, and the rear space for carrying troops. This arrangement became almost standard layout of the later US APCs.
However, the production and maintenance costs of M75 are too high, and it was not amphibious. Therefore, it was replaced rapidly by M59 APC after the Korean War. M59 was developed by Food Machinery Corp (FMC). A ramp was installed at the rear of vehicle that allows loading of large size cargo. The vehicle was designed to be amphibious. All hatches and doors are watertight with rubber seals. A trim vane was installed at the front of vehicle and rubber side skirts to reduce resistance in water.
Both of M59 and M75 have welded steel hulls. The body weight limited their application. In 1950s, Food Machinery Corp. worked with Kaiser Aluminium and Chemical Co. and resulted in successful development of an aluminium alloy that meets demand on both of defense ability and lightweight. In 1956, FMC submitted 2 prototypes of steel and aluminium versions for testing. The test result found that it needs 3 times of thickness for aluminium armour to offer same protection level as the steel. However it saved reinforce structures in steel version. This means that aluminium armour is not only lighter in weight, it also provides more interior space and lower vehicle profile. The improved aluminium prototype T113E1 was adopted and put into mass production in 1960. It was designated M113 by the US army. M113s were supplied to the army of the Republic of Vietnam and soon involved in the Vietnam War. In 1964, the gasoline-engine M113 was supplanted by M113A1 with diesel engine.
The South Vietnamese army is the first unit to equip the M113. In order to avoid casualties of exposed commanders, field modifications were applied in 1963 to provide addition protection. These modifications also affected the US military in later days. FMC therefore developed standardized armour for the exposed crews of M113, and addition weapons mounted outside of the vehicle as well. The M113 was then became a fighting vehicle instead of an original designed personnel carrier. From 1965, the US army issued this upgrade kit to all M113. Thus it became the common version of US army M113 in Vietnam. Most of the upgrade work carried out in Vietnam. The 11th armoured cavalry regiment was the first unit to install upgrade kit in the United States. The upgraded M113 was then suffixed armored cavalry assault vehicle (ACAV). The ACAV upgrade kit was also applied to other vehicles in Vietnam and was seen on other countries’ M113 family after the Vietnam War as well.
(Thanks to AFV Club for the news and the photos.)