LVTP-5

The LVTP-5 (Landing Vehicle, Tracked, Personnel, Model 5) was the US Marine Corps' amphibious tractor, or Amtrac, of the late 1950s and 1960s. Based largely on a Borg Warner design approved by the Navy and Marine Corps in the late 1940s, it went into production in the early 1950s, entered service in 1955-56 and replaced the Amtracs used from the Second World War through Korea. The last one was built by 1957.

Design

Unlike its predecessors the LVTP-5 was roomier and completely enclosed in light armour, and it could swim without preparation once its ports and hatches were closed. Its large, box-like hull was inefficient in the water but gave the displacement needed to float the weight of armour and equipment; bilge pumps removed any water that got in. A bow ramp, lowered by hydraulic motors and winch cables, made beach landings easier, while at sea troops used the large roof hatches. Watertight escape hatches were fitted in both sides.

A crew of three (driver, commander and a third man acting as assistant driver or gunner) sat at the bow. Between 25 and 34 equipped Marines could be seated on four rows of folding benches, or up to 45 standing with the seats removed. As a cargo carrier it could take about 12,000 lb (5,400 kg) afloat and 18,000 lb (8,200 kg) on land. All versions used a liquid-cooled Continental V-12 petrol engine. Early vehicles included an unarmed cargo version and a personnel version with a machine-gun cupola.

Variants

The last batch was upgraded with minor changes to become the LVTP-5A1, identified by a 'dog house' structure on the engine deck and a different final drive. A recovery version, the LVTR1A1, was also built.

Vietnam

Most vehicles had been converted to LVTP-5A1 standard by 8 March 1965, when Marines came ashore at Red Beach 2 in the first major American action in Vietnam, many of them in Amtracs. They were used to land troops from ships, as assault vehicles and as water taxis along the coast and rivers, and later as overland personnel carriers. In that role their thin belly armour was a weakness: mines could rupture the fuel cells under the floor and cause fierce fires, so crews preferred to ride on the roof.