Alternating Current (AC)
An electric current that reverses its direction many times a second at regular intervals.
Anti-Lag/ALS
A system that keeps the turbocharger spinning, and producing boost, at low throttle by igniting air and fuel in the exhaust.
Battery
A device that creates electrical energy from stored chemical energy.
BMS
Battery Management System, which monitors and controls charging and discharging of the battery.
Boost
The pressure of air forced into the engine, and increased power potential, created by the turbocharger.
Cooper Tires
Single supplier of tyres for all categories. Drivers can use up to eight new tyres per event.
Direct Current (DC)
An electric current flowing in one direction only.
Double Joker
Penalty imposed for making a false start, where the guilty driver must pass through the Joker Lap twice in that race.
ECU
Engine Control Unit. Electronic system that controls engine functions.
FIA
Fédération Internationale de l’Automobile – the governing body of world motorsport.
First Reserve Driver
The 13th-placed driver in the Ranking replaces any top 12 driver should they be unable to start in the Semi-Finals. The highest Ranked of the two fourth-placed Semi-Finalists will be first reserve for the Final.
Free Practice
A Friday afternoon ‘shakedown’ for World RX drivers, limited to two runs of four laps each.
G-Force
Where ‘g’ refers to the ‘weight’ created by gravity. So 2.5g experienced under acceleration, deceleration or cornering force etc. refers to 2.5 times ‘normal’ weight.
Gravel/Asphalt
Generalised terms for the mixed surfaces of a rallycross circuit.
HANS
Device acronym for Head and Neck Support, a specific form of Frontal Head Restraint (FHR) which is compulsory for all drivers to wear during races.
Inverter
The device that converts DC from the battery to AC used by the electric motor.
Joker Lap
Longer section of the circuit, which all participants have to take once during each race.
Jump/False Start
Caused by a driver starting before the green light is shown. Controlled by an automated system that monitors every car on the grid. The race is then re-started and the driver in question must take the Joker Lap twice.
Kerbs
Raised and painted track-edge markers placed on corners and chicanes.
Kilowatt (kW)
A measure of one thousand watts of electrical power (power = the rate at which energy is transferred).
Kilowatt Hour (kWh)
A measurement of energy (energy = the rate at which power is made or consumed). 1kWh is 1kW of power supplied for one hour.
Naturally-Aspirated
Referring to an engine, where the air entering the engine is at natural atmospheric pressure (see also ‘Turbocharger’).
Official Practice
Track session before the Heats in each event, offering drivers the opportunity to learn the circuit and prepare for the races. Restricted to a maximum of eight laps per driver.
Paddock
The area where teams set up their awnings/pit garages and hospitality units, and where cars are worked on between races.
Parc Fermé
‘Closed Park’ where cars can be isolated after a race for controlled checks by Scrutineers.
Pre-Grid
Area behind the start-line where cars line up before each race.
Qualifying Practice
For RX2e only – one run of four laps per driver (multiple cars on-track at the same time) to determine grid positions for Heat One.
Ranking
Classification after all four rounds of Heat races, which determines the starting order of drivers in the Semi-Finals and is used to settle any subsequent tie-breaks.
Ready to Race
Board or sign notifying drivers on the start-line that the start of the race is imminent.
RESS
Rechargeable Energy Storage System (a battery).
RX1 (Formerly Supercar)
600bhp internal combustion four wheel-drive cars, capable of accelerating from 0-100km/h in under two seconds – faster than Formula 1. The top class in Euro RX.
RX1e
The pinnacle of the World Championship. Fully electric, four wheel-drive, twin motor rocketships producing 500kW (equivalent to 680bhp) and 880Nm of torque.
RX2e
The first-ever FIA electric rallycross championship when it was launched in 2021, showcasing controlled-spec, one-make, four wheel-drive cars providing a pathway to the top of the sport for aspiring rallycross stars.
RX3 (Formerly Super1600)
1,600cc internal combustion front wheel-drive cars competing in their own FIA European Championship, which features on the support programme at selected World Championship events.
Scrutineering
Pre- and post-event technical and safety checks of cars to ensure their compliance with the regulations. Carried out by Scrutineers.
Sealed/Unsealed
Various surfaces of the circuit, sealed typically being asphalt and unsealed being gravel.
SOC
State of Charge – equivalent of fuel gauge for a battery. Measured in % where 0% is empty and 100% is full.
Spotter
Member of the race team informing his or her driver on position and timing, and advising on Joker Lap strategy via radio communication.
Suspension
The combination of springs, dampers and fixing links that connect the wheels to the car and by which wheel movement is controlled.
SuperPole
A single-lap shootout from a standing start for World RX drivers, used to determine grid positions for Heat One.
Top Qualifier/TQ
First-placed driver in the Ranking at the end of the Heats. Starts on pole position in Semi-Final 1.
Torque
The rotational force of an engine or motor. Most usually measured in Newton-metres (Nm).
Turbocharger
A method of forced induction (opposite of Naturally-Aspirated) which uses a compressor driven by exhaust gases to increase the pressure and quantity of air entering the engine, allowing increased power output.
Tyre-Cleaning
Non-compulsory process prior to lining up on the grid where drivers warm their tyres and rehearse their start procedure, with the resulting wheelspin ‘cleaning’ the surface of the tyre.
Watt (W)
The international unit of power.