Riot Control Vehicle

Overview

A riot control vehicle is a heavy armored truck that disperses crowds with a controlled jet of water. The water cannon is a less-lethal tool: a strong stream pushes people back and breaks up a line without the lasting injury of impact rounds. The vehicle has to carry several tonnes of water, project it accurately at distance, and survive being pelted with rocks, bottles, and petrol bombs while it does so. Everything on the vehicle serves one of those three needs.

The major systems are the Armored Cab that shelters the crew, the heavy Truck Chassis and Powertrain that carry and move the load, the Water Delivery System that does the work, and the Self-Protection Kit that keeps the vehicle running under attack.

Crew protection

The crew sit inside the Armored Cab. Its Cab Armor Panel panels stop rocks, bottles, and handgun rounds, and a Fire-Resistant Skin treatment lets petrol-bomb flame run off and burn out without igniting the structure. The driver sees forward through a Ballistic Windshield, a thick glass and polycarbonate laminate, and when the situation worsens a hinged Window Grille folds down over the glass to take the heaviest impacts. Each Armored Cab Door seals at its edge so irritant agents and the vehicle's own water spray cannot leak inside.

Chassis and powertrain

A loaded riot vehicle weighs 20 to 30 tonnes, most of it water, so it rides on a heavy Truck Chassis. Two Frame Rail members tied by Cross Member braces resist the surge of a partly filled tank. The Front Steer Axle steers, and a Tandem Drive Bogie of two driven axles spreads the rear load over more tyres. An Air Spring suspension keeps ride height constant as the tank drains, with Shock Absorber dampers controlling the sway of the high load. Hubs run on heavy Ball Bearing sets.

The Powertrain does double duty. A Turbodiesel Engine of 9 to 12 litres drives the road wheels through an automatic Automatic Transmission and three Drive Shaft units, and a Power Take-Off takes power off the transmission to spin the water pump while the vehicle is creeping or stationary. A large Cooling Pack keeps the engine cool while it drives the pump with no road airflow.

Water delivery

The Water Delivery System is the reason the vehicle exists. The Water Tank holds 8 to 12 cubic metres, with internal baffles that stop the water from sloshing and unsettling the truck. A power-take-off-driven High-Pressure Pump raises it to 15 to 20 bar and feeds the Distribution Manifold, where a Valve Block routes flow to each outlet.

Two Roof Water Cannon cannons on pan-tilt mounts do the dispersing. Each switches between a wide fan for area effect and a focused stream that reaches 60 to 75 m. The water capacity of 8 to 12 cubic metres sounds large but drains fast at full flow, so the operator works in short bursts and the tank is refilled from hydrants between engagements. The pressure is set high enough to deter and move a crowd but kept below the level that would cause serious injury, a balance the design must hold across the full range of the cannon. Around the body, Self-Protection Nozzle outlets spray a sheet of water to wash attackers off the vehicle and douse petrol-bomb fire. Pressure and tank level are watched by a Pressure Sensor at the pump, and an interlock cuts the cannons when the tank runs low so the pump is never run dry.

Aiming and control

The crew run the system from the Control System. At the Operator Console, a joystick aims the cannons and sets the jet shape, while an Aiming Camera slaved to each cannon and a cab Operator Display let the operator aim accurately without exposing himself. The System Controller drives the cannon actuators, meters any additives, and monitors pump pressure and tank level.

Self-protection

The Self-Protection Kit keeps the vehicle working while it is pelted and rammed. Every light and mirror sits behind a Lamp Grille, a Deflector Plate sheds heavy objects off the body, a Run-Flat Tyre survives slashing, and an Underbody Shield guards the powertrain and pump from objects rolled beneath the vehicle.

Dispersal aids

Where law allows, the Dispersal Aids add effect to the jet. A Marker Dye Tank marks individuals with coloured dye for later identification, an Irritant Tank holds a concentrated irritant, and an Additive Injector Pump doses either additive into the stream at a set ratio. A Smoke Generator can lay a screening cloud to separate sections of a crowd.

Communications

The Communications Suite keeps the crew linked. A multi-band Radio Set reaches command on a protected Roof Antenna, and the Loud Hailer loud hailer broadcasts the lawful warnings that must precede the use of water.