Amphibious ATV

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      The Amphibious ATV is a six-wheeled light survey and exploration vehicle, normally provided to large Science teams. A simple rectangular frame supports the power supply, engine, and open-topped Resistweave fiberglass body. It has a foam-padded vinyl-covered bench seat for two persons, and a small cargo deck which could hold another person -- very awkwardly. There is no windshield, mirrors or rollbar. Steering is accomplished by braking all the wheels on one side -- very inefficient, but it does allow the ATV to skid-steer in a zero-radius circle.

     Derived from the Mobility Unlimited Amphicat, this Morrow Project vehicle benefits from anachronistic battery technology.


As seen in television on the Banana Splits children's show, and the Space: 1999 science-fiction show.




Crew:  2

Weight:  empty, 218 kg; loaded, not more than 436 kg; payload is thus 218 kg

Length:  2.05 m

Width:  1.35 m

Height:  0.86 m

Ground clearance:  0.15 m (under hull)

Turning radius:  zero

Ground pressure:  0.07 kg/square centimeter

Max speed: 

(highway) 50 kph

(road) 19 kph

(water) 2.4 kph

Fording:  amphibious

Gradient:  70% when fully loaded

Engine:  4 kilowatt electric motor

Electrical system:  240 V; there are two headlamps, and a recharging plug for the batteries

Batteries:  twenty Morrow Project vehicle batteries



     The batteries store a total of 30 kilowatt-hours of electrical power, or enough electricity to run the motor at full power for 7.5 hours. The batteries have Morrow Industries data plates; their name is given on the plates as "Vehicle Battery, 240 Volt". An Electrical Repair or Electronics skill roll will identify the batteries as being futuristic technology. The electric motor is expensive but contemporary, coming from a typical American manufacturer. A watertight hatch in the cargo deck gives access to the battery and motor compartment.

     The suspension is of the solid axle type, with no springs or shock absorbers of any kind -- in fact the six axles are mounted rigidly to the frame, and any cushioning of the ride is provided by the low-pressure (only 1.5 psi) tires. The limitation on payload size is mostly based on the load rating for the tires.

     Steering is accomplished by applying the brakes to all three wheels on one side (skid steering).

     The ATV is fully amphibious, propelled in the water by its wheels; freeboard when fully loaded is 0.4 meters.

     When lightly loaded, the ATV has sufficient power and torque to attempt climbing dangerously steep grades. Driver skill, rather than vehicle power, will determine the maximum slope that can be traversed.

     Controls consist of an accelerator pedal, a direction control lever (forward or reverse), a parking brake lever, and two steering brake levers. An on/off switch, a headlamp switch, and a 24 volt military accessory jack complete the dashboard items.

    There are four lifting eyes/towing points, one near each corner just below the body midline, and a simple, small towing pintle at each end. 


Maintenance and Installed Equipment


     Since the internal combustion engine has been entirely replaced, keeping the vehicle operating is much easier -- but it still needs maintenance.





     A transom mount for an outboard motor was available; it's unknown if the Project made any use of this. Fitted with a low-power outboard motor the ATV can reach 4.2 kph. Any attempts to increase water speed past that point will result in the ATV taking on water over the nose and sides. 

     A very simple amphibious trailer can be towed behind the ATV. The trailer is an open-topped Resistweave fiberglass tub with two Amphicat wheels and tires, and can carry about 220 kg of cargo and maintain a reasonable freeboard. It has no brakes, not even a parking brake -- it's about as complex as a wheelbarrow. Empty weight, 40 kg.

    The wheels of the ATV (and the trailer) can be removed and replaced with hub adapters and pressed-steel railway wheels; the middle axle of the ATV is fitted with a "blind" (un-flanged) set of wheels. The hub adapters can be adjusted for any gauge from 3' narrow up to 4' 8.5" standard. Each wheel and hub adapter weighs 5 kg. The ATV will  squeal a bit going around tight curves (as on streetcar track), but shouldn't have that problem on "regular" railway lines.


In theory, the payload of the Amphicat or trailer could be doubled when used with the railway wheels;

but the Project didn't endorse such overloading.