The smallest U.S. aircraft carrier during the Vietnam War
During the Vietnam War, the U.S. Navy initiated a riverine ship development program, known as Program 4, which consisted of using existing landing craft to convert them into a number of different types of riverine ships, including one that was dedicated to transportation duties, the Armored Troop Carrier (ATC). These include the Armored Troop Carrier (ATC), which specializes in transportation. Because of their size and space, these ships could carry a large amount of armaments to support ground combat troops. After some research, the U.S. Navy decided to select the LCM-6 Mod 1 mechanized landing craft for conversion.
After a series of modifications, there is a huge difference between the ATC and the prototype LCM in terms of appearance, with the exception of the bow skips, there is basically no **** between the two. In terms of size and tonnage, the ATC is significantly larger than the LCM, with a displacement of 70 tons, a length of 17 meters, a width of 5.3 meters and a draft of about 1 meter.
The crew of the ATC consisted of seven men, including the captain, coxswain, radioman, mechanic, and three gunners. one ATC was capable of transporting a fully armed rifle platoon (40 men), and four were capable of transporting a full infantry company. In addition, the cargo hold was capable of holding a 105mm howitzer, an M113 APC, a 3/4-ton truck, or 11 tons of cargo.
The Type 1 ATC also had a variant with a removable helicopter landing platform mounted on top of the cargo hold, turning it into an Armored Troop Carriers Helicopter (ATCH). The landing pad extends from the front of the cockpit to behind the bow ramp, where a Huey UH-1 helicopter can land and take off. The helicopters are primarily battlefield ambulances, and one or two are assigned to each riverine assault squadron.
The boats are usually manned by a surgeon and a medic, hence the name "medevacs" or "medical boats". When fighting on the front line, the wounded from other ships or ground troops would receive first aid on board, stabilize their injuries, and then be transported by helicopter to a field hospital in the rear.
The helicopters can also perform supply and communications duties, and three-quarters of the Type 2 ATCs in Program 5 were fitted with an armored landing platform and additional horizontal protection for the cargo compartment, which can withstand 82mm mortar rounds. The platform can be accessed from two inclined escalators in the center of the hull, and there is also a vertical escalator to the helipad at the bow near the diving board, with a hatch at the top exit. Although the air platform on the river is not very stable, and every takeoff and landing needs to be careful, but the existence of this ship does provide special convenience for riverine operations, and has been called "the world's smallest helicopter carrier".