This open-backed Thiokol 1300 Swamp Spryte amphibious ATV, based on the successful Thiokol Spryte Snowcat, was not available with an enclosed cabin

Small off-road, and typically amphibious 6x6 vehicles were developed in the early 1960s and quickly became popular in both the US and Canada. Once it established itself as a popular vehicle to enthusiasts and professionals worldwide, the concept of these vehicles earned its own classification, coining the term all-terrain vehicle - or ATV. [1] However, after the introduction of small three- and four-wheeled off-road motorcycles in the 1970s and 1980s, these have become more well-known as ATVs than the original vehicle type, leaving that type now known as AATV or Amphibious All-Terrain Vehicle.

History

ATVs were made in the United States a decade before 3- and 4-wheeled ATVs were introduced by Honda and other Japanese companies. An all-terrain vehicle (ATV is defined by the American National Standards Institute (ANSI as a vehicle that travels on low pressure tires with a seat that is straddled by After the presentation of the Jiger in 1961, numerous manufacturers offered a number of similar small off-road vehicles, that were designed to float and were capable of traversing swamps, ponds and streams as well as dry land. Because they were smaller and much simpler in construction than (amphibious) cars, they were much cheaper to produce and quickly gained considerable popularity. By 1970 there were almost 60 companies producing amphibious 6x6 vehicles. There was even a professional racing association dedicated to the 6x6, holding numerous competitions across the USA. These amphibious vehicles were originally called all-terrain vehicles - or ATVs. An amphibious vehicle (or simply amphibian) is a Vehicle or craft, that is a means of transport viable on land as well as on water - just like an

In the early 1970s however there was a rapid decline in sales of this type of ATVs, forcing most manufacturers to cease production. Reasons were:

• the 1973 oil crisis prompted many North Americans to tighten their belts and spend less on recreational vehicles.
• the introduction of the 1970 Honda ATC90 threewheeler offered a fun alternative at some $600 / $800, when a 6x6 would cost $1,500.
• The simple construction of the original ATVs attracted many companies that were interested in making a quick buck, but underestimated the engineering needed, leading to poor quality products, that gave the industry a bad reputation.

Only a small number of manufacturers of this type of vehicle remain today.

Characteristics

Although many differing variants have been developed over the years, and new ones are still being devised, most amphibious ATVs share most of the following characteristics. In contrast to todays ANSI definition of an ATV: "a vehicle that travels on low pressure tires, with a seat that is straddled by the (single) operator, and with handlebars for steering control", an AATV is intended for multiple riders, sitting inside, and will usually have steering wheels or control sticks rather than motorcycle-type handle bars as stipulated in the current definition. Typically constructed with a hard plastic or fiberglass watertight body"tub", AATVs usually have six or eight wheels - all driven - with low pressure (around 3 PSI) balloon tires, no suspension (other than what the tires offer) and no steering wheels. Directional control is accomplished through skid-steering - just as on a tracked vehicle - either by braking the wheels on the side where you want to turn, or by applying more throttle to the wheels on the opposite side. Most contemporary designs use garden tractor type engines, that will provide roughly 25 mph top speed. AATVs typically do not meet automobile legislation in most countries, and are therefore strictly Off Highway Vehicles.

Though not as fast as a straddled ATV, the amphibious 6x6 and 8x8 can be operated with precision at slow speeds, carry more passengers and cargo, and of course, has the ability to float. Although the spinning action of the tires is enough to propel the vehicle through the water - albeit slowly - outboard motors can be added for extended water use.
On land the combination of a large number of wide wheels and tires, low tire pressure and low vehicle weight, all result in exceptionally low ground pressure, high grip and off-road ability. Nevertheless for further enhanced off-road, snow and mud performance, optional tracks can be mounted directly onto the wheels.

Manufacturers and models

Brands / models no longer in production include:

• The Jiger, the worlds first to produce ATVs, starting in 1962,
• The Amphicat, ca. The Amphicat was a six-wheel-drive skid steer amphibious all-terrain vehicle manufactured in the late 1960s through the early 1970s by Mobility Unlimited Inc of Auburn Heights Michigan 1965 - 1975
• Attex produced several models from 1968 - 1983, some stood out due to their high 55 mph top speed
• The Coot, that featured an articulated twin hull, to keep its four wheels driving all the time (still amphibious !). In production from 1967 - 1985.

Current brands of these machines include:

• HydroTraxx , the only fully hydraulic drive 6x6
• Argo, manufacturer of 6x6 and 8x8 models
• Land Tamer, steel or aluminium hull heavy duty 6x6 or 8x8
• MAX, producing several compact 6x6 models
• Triton Predator, featuring a hydrostatic drive system
• Gibbs Technologies, their Quadski is the world's first high speed amphibian ATV

External links

• For more information on amphibious ATVs, see 6x6 World's Amphibious ATV FAQ, or view their comprehensive Amphibious ATV Image Gallery for pictures of various machines.
• For more information on amphibious ATVs, see www. route6x6. com's FAQ page, Information Bank and Museum pictures pages.
• The amphibiousvehicle. net Amphiclopy also includes information on many known AATVs.