RC racing glossary, A to Z.

Definitions here say what a term means and who uses it; they are not instructions. Nothing on this page describes how to drive, build, assemble, set up, tune, solder, wire, run in an engine, mix or handle fuel, charge, balance, store, dispose of or repair anything, and no gear named here (a LiPo sack, a hard case, a barrier or anything else) is presented as preventing fire or injury or as making racing safe or legal. Injuries, fuel exposure and battery fires are named here only, never treated: any injury or fuel exposure needs medical care, and a burning battery or a fuel fire is a matter for the fire service.

Racing rules belong to the body that writes them and apply only at that body's events, so each rule is given with its body and document: IFMAR's World Championship rule books (1/8 IC off-road 2024, 1/8 IC track 2023, 1/10 IC track 2024, 1/8 GT and GTE 2025, electric off-road 13 November 2019, electric batteries and motors March 2023, 1/8 e-buggy April 2023), the EFRA Handbook 2026 (Appendices 3, 4 and 8) and EFRA's 2024 General Rules (the 2026 General Rules were not read), ROAR's National Guidelines revised 13 October 2026 and its dated announcements (ROAR's current rule book was not read, so every ROAR figure says what it rests on), and the BRCA's own pages (its 2026 section rules were not read). Racing rules are not law. Radio law is given one jurisdiction at a time, each with its regulator and rule: the United States (FCC, 47 CFR Part 95 Subpart C, read on Cornell's Legal Information Institute because fcc.gov could not be read), the United Kingdom (SI 2021/493 and IR 2030; Ofcom's own pages could not be read), Europe (CEPT and Directive 2014/53/EU), Canada (ISED) and Australia (ACMA, unconfirmed). Where sources disagree, each version is given with who says it; items resting on a search summary, a headline or a single report are labelled unconfirmed, Wikipedia is named wherever it is the source, and makers' statements are labelled as claims. Events are as the research recorded them on 30 October 2026.

Jump to: 0-9 A B C D E F G H I J K L M N O P Q R S T U V W Z

0-9

05 motor

EFRA's name for the standard brushless motor size used in 1/12, 1/10 touring car and 1/10 off-road racing. Under the EFRA Handbook 2026, Appendix 4 (batteries and motors) (section 4), an 05 motor has a can 34.00 to 36.02 mm across and 50.0 to 53.0 mm long, must be rebuildable and may not be modified; IFMAR's electric batteries and motors rules (March 2023) use the same can size, and IFMAR approves only 05 brushless motors for its electric World Championships. EFRA has allowed only motors on its homologation lists at its electric European Championship and Grand Prix events since May 2016 (Appendix 4, section 5, gives 1 June 2016). (Motors)

100 Wh and 160 Wh (IATA)

The watt-hour lines in IATA's passenger guidance on lithium batteries (31 March 2026, based on the 2025-2026 ICAO Technical Instructions and the 67th edition of the IATA Dangerous Goods Regulations). Spare lithium-ion batteries of 100 Wh or less travel in carry-on baggage only, without operator approval; spares above 100 Wh and up to 160 Wh need operator approval and stay in carry-on; above 160 Wh, batteries go only as cargo. IATA says Wh equals ampere-hours times nominal voltage, requires batteries to be of a type meeting UN 38.3, and calls its document guidance only. It defines only lithium-ion and lithium metal batteries and never names lithium polymer or model cars, so this site does not say which band a LiPo racing pack falls into; US limits from the FAA and PHMSA could not be read. The EFRA Handbook 2026, Appendix 4 (batteries and motors) (1.7) says EFRA approves only batteries within passenger airlines' maximum energy capacities. (Travelling with batteries)

1/10 electric off-road (2WD and 4WD)

The 1/10 electric buggy classes, raced as two separate titles. IFMAR's electric off-road rules (version of 13 November 2019) cap length at 457.2 mm and width at 250.0 mm; the 2WD class is rear-wheel drive only (front-wheel-drive cars run in 4WD) with a minimum weight of 1.474 kg, and 4WD cars need effective front drive and weigh at least 1.588 kg. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) gives the same width and weights but a maximum length of 460 mm, so the two bodies' length limits differ. Wikipedia dates the first IFMAR 1:10 electric off-road World Championship to 6 to 11 July 1985 at Del Mar, California; other venue lists were not read and no IFMAR record of the venue was found, so the venue rests on Wikipedia alone (unconfirmed). (Chassis and scales)

1/10 electric touring car (ISTC)

The 1/10 electric touring car, called ISTC (International Scale Touring Car) by IFMAR. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) requires bodies modelled on real touring cars at least 420 mm long and homologated by EFRA, a width of at most 195 mm with body, a minimum weight of 1320 g, a fixed single-ratio transmission and independent suspension on all four wheels; EFRA's European Championship classes are Modified and 13.5T spec. IFMAR's ISTC rule book was not read. LiveRC says IFMAR first recognised the class as a provisional World Championship class in 1998 at Newcastle, England; no other source dating the first ISTC Worlds was read, so the date rests on LiveRC's account. (Touring cars and new classes)

1/10 Formula One (EFRA)

EFRA's 1/10 electric Formula One class. Under the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4), cars are at most 200 mm wide, weigh at least 1050 g on rubber tyres or 1010 g on foam tyres including a personal transponder, carry Formula 1 body styles with a driver figure and use only 21.5T spec brushless motors. The BRCA runs Formula One within its two-wheel-drive electric circuit class. (The classes)

1/10 front-wheel drive (EFRA FWD)

EFRA's 1/10 electric touring car class in which only the front wheels are driven. Under the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4), FWD cars have independent suspension on all four wheels, a width of at most 195 mm and a minimum weight of 1250 g including the personal transponder, carry homologated hatchback bodies with all electronics inside the shell, and use 21.5T spec brushless motors with a blinky speed controller. (The classes)

1/10 IC track (200 mm nitro touring car)

IFMAR's 1/10 nitro on-road class, run as the 200 mm Nitro Touring Car. Under IFMAR's 1/10 IC track World Championship rules (2024 edition), cars are four-wheel drive with a single brake on the central transmission and at most a 2-speed gearbox; engines are at most 2.11 cc (.12), air-cooled two-strokes with glow plug ignition only, no forced induction and a carburettor of at most 5.50 mm; minimum weight without fuel is 1650.00 g including transponder, the tank holds 75.00 cc, and bodies reproduce 1:10 touring cars. Its fuel may hold at most 16 percent nitromethane by volume, against 25 percent in IFMAR's 1/8 IC rules. (Nitro engines and mufflers)

1/12 electric track

The 1/12 electric on-road class, raced indoors on carpet under EFRA's rules. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) splits it into LMP (Modified, with motors of no less than 6.5 turns, and Spec 13.5T) and a 17.5T GT class; the rear end is a single solid axle with no independent suspension (a differential is allowed), and the battery is a 1S lithium pack of at most 3.8 V nominal, which Appendix 3 dates from 1 March 2017 while the EFRA Handbook 2026, Appendix 4 (batteries and motors) says 3.8 V cells have been allowed since 1 April 2017. IFMAR's electric batteries and motors rules (March 2023) also limit 1/12 to 1S packs (3.8 V LiPo, 3.3 V LiFe). IFMAR dates its first electric World Championship, for 1/12 stock and modified, to 1982. (The classes)

1/5 large scale

The largest racing scale. IFMAR publishes 1/5 IC track World Championship rules (2024 edition), and Red RC reported 145 registered drivers at the 2026 Large Scale World Championship in Lostallo, Switzerland, the twelfth such event and the first since 2022. EFRA runs a Large Scale section for track and off-road, and the BRCA's Large Scale Off Road national series uses petrol engines of 23, 26, 30 or 32 cc in 2WD buggy, 4WD buggy, short course and open classes. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) say large-scale racing has no marshals, with mechanics marshalling from the pit lane. (Touring cars and new classes)

1/8 e-buggy

IFMAR's name for 1/8 electric off-road racing. Under IFMAR's 1/8 e-buggy rules (April 2023), cars use lithium packs of at most 15.2 V nominal (4S, as one 4S, two 2S or four 1S packs of one brand and part number), charged to at most 4.20 V per cell (16.80 V for 4S), and 4WD cars weigh at least 3.2 kg ready to race. LiveRC reported EFRA's first official European Championship for 1/8 electric buggy in 2015 at Fehring, Austria. When the class's IFMAR World Championship began is reported both ways: Wikipedia's text says the class was added in 2024 while its own navigation lists it from 2025, and Hobbywing, a motor and speed-controller maker, claims the 2025 event as the inaugural one. (Off-road arrives)

1/8 GT and GTE

IFMAR's 1/8 four-wheel-drive GT classes, nitro (GT) and electric (GTE). Under IFMAR's 1/8 GT and GTE rules (2025 edition), GT cars run 3.5 cc engines with a tank of at most 150 cc, are at most 590 mm long with a body 300 to 317 mm wide, weigh at least 3500 g with an empty tank, use fuel of at most 16 percent nitromethane by volume and race 7-minute heats on one tank with no refuelling; GTE cars use at most 4S LiPo, in one pack or two equal packs, in a mandatory hard case, at most 16.80 V at the start of a race, with each battery at most 100 Wh and, for 2025, homologated or approved on a list published three months before an event, and weigh at least 3800 g. EFRA's IC Track section covers GT8 and GT8E. (The classes)

1/8 IC off-road (nitro buggy)

The 1/8 nitro buggy class. Under IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024), cars have engines of at most 3.5 cc with no tolerance and a tank, filter and lines of at most 125 ml, are at most 550 mm long and 310 mm wide on a 270 to 330 mm wheelbase, weigh at least 3.2 kg ready to race without fuel (4WD), need brakes and a clutch that hold the car still with the engine running, and use only IFMAR-homologated silencers; the World Championship field is capped at 180 drivers. EFRA runs the class through its 1/8 Buggy section, and ROAR's National Guidelines (revised 13 October 2026) list fuel off-road among the Nationals categories. (The classes)

1/8 IC track (nitro on-road)

The 1/8 nitro on-road class. Under IFMAR's 1/8 IC track World Championship rules (2023 edition), engines are at most 3.5 cc with a 125.00 ml tank system and a carburettor of at most 9.00 mm, liquid-cooled engines are banned, cars weigh at least 2350 g, run a controlled tyre at World Championships and carry bodies reproducing full-size sports or prototype racing cars. IFMAR's own history names 1/8 IC track as the class of its first championship, Indianapolis 1981, after events at Pomona in 1977 and Geneva in 1979, while Wikipedia calls the 1977 race the inaugural world championship. (The classes)

1S, 2S and 4S

Cell counts: the number of lithium cells in series in a racing pack, written as a number followed by S. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) and IFMAR's electric batteries and motors rules (March 2023) give 1/12 cars a 1S pack (3.8 V nominal for LiPo, 3.3 V for LiFe) and 1/10 touring, Formula One and off-road cars (and, in EFRA's rules, front-wheel-drive cars) a 2S pack (7.6 V LiPo, 6.6 V LiFe); IFMAR's 1/8 e-buggy rules (April 2023) allow 1/8 electric off-road cars at most 15.2 V nominal (4S), and the EFRA Handbook 2026, Appendix 4 (batteries and motors) sets 4S case sizes and voltages, though EFRA's own 1/8 electric class rule was not read. No standard defining the S count by that name was read, so the term is given only as these rule books use it. (Battery rules by body)

2.4 GHz radio

The band most racing transmitters now use. IFMAR's 1/10 IC track World Championship rules (2024 edition) say about 99 percent of drivers use 2.4 GHz systems, which IFMAR's rule books call DSM/DSS systems and allow alongside crystal-controlled transmitters where the host country permits them. In the United States, 47 CFR 15.247 (the FCC's rule as published by Cornell's Legal Information Institute) sets limits for unlicensed devices in 2400 to 2483.5 MHz, but no FCC or other regulator text read ties 2.4 GHz car radios to that section. Model Aviation (March 2007) dates Spektrum's first production 2.4 GHz system, for surface use, to about late 2005, while Fly RC dates Spektrum's aircraft system to late 2005 without mentioning cars; both are trade accounts of a maker's products, so neither first is a confirmed claim. Racing rules are not law. (Radios and receivers)

25 percent and 16 percent nitromethane (IFMAR)

IFMAR's two fuel limits, which depend on the class. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) and IFMAR's 1/8 IC track World Championship rules (2023 edition) allow fuel of methanol and/or ethanol, lubricating oil, a little anti-corrosion additive and at most 25 percent nitromethane by volume (specific gravity no more than 0.91 g/cc at 20 C), while IFMAR's 1/10 IC track World Championship rules (2024 edition) allow at most 16 percent (0.87 g/cc); all three name hydrazine, hydrogen peroxide, toluene and propylene oxide as banned. IFMAR's 1/8 GT and GTE rules (2025 edition) also set at most 16 percent nitromethane by volume (0.87 g/cc, rule 4.2) for the GT class. At World Championships IFMAR uses controlled fuel from up to three brands (1/8 IC track rule 5.23). The European Union's threshold for nitromethane is a separate law, given under its own entry. Racing rules are not law. (Nitro fuel rules)

27 MHz channels

Shared model-control channels, given separately by each regulator. United States: 47 CFR 95.763 (the FCC's Radio Control Radio Service, as published by Cornell's Legal Information Institute) lists six channels from 26.995 to 27.255 MHz, and 95.731 (read only as an unofficial copy of the 2017 text) lets the 26 to 28 MHz band control any kind of device. Europe: CEPT's ERC Recommendation 70-03 model-control annex lists five narrow sub-bands between 26.990 and 27.200 MHz at 100 mW e.r.p., not harmonised and not exclusive to models. United Kingdom: Ofcom's pages could not be read; a search summary says IR 2030 lists 26.960 to 27.280 MHz for general model control (unconfirmed). (Radio rules by country)

2WD and 4WD

Two-wheel drive and four-wheel drive, the split in 1/10 electric off-road racing. IFMAR's electric off-road rules (version of 13 November 2019) run them as separate World Championship titles, with 2WD rear-wheel drive only and 4WD cars needing effective front drive; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) also runs both classes and lets drivers enter both. Wikipedia says ROAR and JMRCA first split unlimited off-road racing into 2WD and 4WD in 1986 and that the split was used at the 1987 Worlds; no ROAR, JMRCA or IFMAR document confirming this was read (unconfirmed). (Off-road arrives)

3.8 V nominal (EFRA)

The highest nominal rating EFRA allows for a lithium polymer (LiPo) cell; LiFe cells are rated at no more than 3.3 V. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (rule 1.4) says 3.8 V cells have been allowed since 1 April 2017 and that earlier 3.7 V approvals stand, while the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (A 3.1) gives 1 March 2017 as the date for 3.8 V 1/12 batteries; both dates are EFRA's own. IFMAR's electric batteries and motors rules (March 2023) use the same 3.8 V and 3.3 V cell ratings. (Battery rules by body)

40 MHz model control (Europe)

A band set aside for model control in Europe. CEPT's ERC/DEC/(01)12 (adopted 12 March 2001, last updated 10 June 2022) harmonises 40.665, 40.675, 40.685 and 40.695 MHz for model control and exempts such devices from individual licensing, and CEPT's ERC Recommendation 70-03 annex lists 40.660 to 40.700 MHz at 100 mW e.r.p. In the United Kingdom, a search summary of Ofcom's page says 40.660 to 41.000 MHz is for surface models only (unconfirmed, because Ofcom's pages could not be read). (Radio rules by country)

4.20 V per cell

The highest charged voltage EFRA and IFMAR allow for a lithium polymer cell at their events. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (rule 2.7) caps packs at 4.20 V for 1S, 8.40 V for 2S and 16.80 V for 4S (LiFe: 3.70 V, 7.40 V and 14.80 V); IFMAR's electric batteries and motors rules (March 2023) cap 2S at 8.40 V and 1S at 4.20 V; IFMAR's 1/8 e-buggy rules (April 2023) cap 4S at 16.80 V, checked before any run. Both bodies call overcharging a safety hazard and penalise it. ROAR's battery rules as LiveRC reprinted them in 2011 allowed 4.25 V per cell (8.50 V for 2S); whether that is still ROAR's figure was not confirmed. (Battery rule checker)

72 MHz and 75 MHz (United States)

The two US Radio Control Radio Service bands, as the FCC's rules state them on Cornell's Legal Information Institute: 47 CFR 95.763 lists fifty channels from 72.01 to 72.99 MHz and thirty from 75.41 to 75.99 MHz, and 95.731 (read only as an unofficial copy of the 2017 text) reserves 72 MHz for model aircraft and 75 MHz for model surface craft such as cars. Under 95.787, 72 and 75 MHz transmitters need a built-in antenna and plug-in crystals must not be user-accessible, and 95.305 lets eligible people operate Part 95 stations without an individual licence. Model Aviation (September 1999) dates the 72 MHz aircraft set to 1982 and pairs a similar 75 MHz surface set with it, giving the surface set no year of its own, so the 75 MHz date rests on that pairing; the FCC's own history was not read (unconfirmed). (Radio rules by country)

83 dB (EFRA's statement)

A noise figure in EFRA's muffler rules: the EFRA Handbook 2026, Appendix 8 (mufflers) states that 83 dB is the European Community's permitted noise level without extra personal protection. That is EFRA's statement about EU legislation, which was not read, so the figure is unconfirmed as a legislative limit, and no regulator noise rule specific to RC tracks was found. EFRA sets each event's own noise limit before timed practice. (Noise and mufflers)

85 dB at 10 m

IFMAR's muffler noise limit. IFMAR's 1/8 IC track World Championship rules (2023 edition) require homologated mufflers of at least three chambers with homologated inlet noise silencer boxes, and set 85 dB, measured at 10 m distance and 1 m height, as the maximum for a muffler with its silencer box; IFMAR's 1/10 IC track World Championship rules (2024 edition) test each double-chamber muffler for homologation on an engine at 40,000 rpm against the same 85 dB at 10 m and 1 m. No regulator noise rule for RC tracks was found. (Noise and mufflers)

A

AARCMCC

Australia's national RC car body. Wikipedia's FEMCA member table lists it as founded in 1979 and as a national member of FEMCA, so the sources read place it inside the FEMCA bloc rather than as a separate IFMAR bloc. Its full name is spelled two ways: an IFMAR stage report gives Association of Australian Radio-Controlled Model Car Clubs (seen only in a search summary, unconfirmed) and Wikipedia gives Association of Australia Radio Controlled Model Car Club. No AARCMCC rule book or AARCMCC page was read. (The BRCA and national bodies)

ACMA (Australia)

Australia's radio regulator. A search summary of ACMA's class licence page says radio-controlled models are covered by the Radiocommunications (Low Interference Potential Devices) Class Licence 2025 with no application needed; the ACMA page timed out and the licence text was not read, so this is unconfirmed and Australian model-control bands are not given here. (Radio rules by country)

Affiliated track (IFMAR)

A track membership IFMAR offers. IFMAR's associated membership document (7 March 2021) says affiliation does not by itself qualify a track to host a World Championship, and sets minimum requirements: indoor tracks at least 120 m long or a 15 by 30 m space, outdoor tracks at least 250 m, liability insurance for drivers and visitors, IFMAR-approved timing with live timing, and compliance with local safety requirements. ROAR's National Guidelines (revised 13 October 2026) require Nationals hosts to be current ROAR track affiliates when they bid. (IFMAR and the blocs)

A-main

The top final at a race meeting, run differently by each body. ROAR's National Guidelines (revised 13 October 2026) run AAA mains, in which the A main is run three times, in electric classes with three full heats; the BRCA's 2026 South West 10th off-road regionals give A-main drivers a three-leg final of 5 minutes, with all other finals one leg; IFMAR's electric off-road rules (version of 13 November 2019) run the A-Main as three separate five-minute finals of ten drivers, with the best two counting. IFMAR's IC classes instead build up to a single main final through ladder finals. (How a race meeting works)

Approved list

A body's published list of the equipment allowed at its events, which decides what may race there. the EFRA Handbook 2026, Appendix 4 (batteries and motors) says only batteries shown on EFRA's website lists may race at EFRA-sanctioned events, and EFRA also lists homologated motors, blinky speed controllers, bodies and registered mufflers; IFMAR's electric batteries and motors rules (March 2023) provide an Approved Product List of batteries and a list of approved motors for each World Championship; ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) makes it the driver's responsibility to know whether a motor, battery, speed controller or body is on the latest ROAR Approved List. Being on one body's list says nothing about another body's events. (Approved equipment lists)

Asia Championship (FEMCA)

The title under which FEMCA has been running its championship events, as Red RC describes it. Red RC reported on 17 November 2025 that FEMCA had awarded its first Asia 1:8 GT Nitro Championship, also catering for electric GT. No FEMCA rule book or FEMCA web page was found, so FEMCA's events rest on trade press. (FEMCA and Asia 2026)

Associate member (makers)

A non-voting membership for manufacturers. IFMAR's associated membership document (7 March 2021) gives makers a seat on a technical committee that may make technical proposals only, with no voting rights and no proposals on general rules or the constitution; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) give manufacturer associate members no vote at EFRA meetings but let them submit proposals and take part in section meetings. (IFMAR and the blocs)

B

Barriers

Track barriers between the cars and people, required by rule. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (rules 5.3.3 and 5.3.4) require adequate barriers between the cars and spectators, competitors and officials, and corner markers placed so that cars hitting them at full speed cannot fly into the public; IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (rules 3.8 and 3.8.d) set the same requirements at World Championships. These are rule requirements, not a finding that a barrier stops injury. Any injury needs medical care. (Track and rostrum rules)

Baton (EFRA marshal post)

A plastic or wooden baton that EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (rule 8.15) make mandatory at marshal positions at IC (nitro) events, for safety reasons, as an aid to stop a running engine. (Marshalling and officials)

Black flag

A flag that calls a car into the pits. Under IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (rule 3.29), the all-black flag is shown with a car number at the order of the race director or referees, and ignoring it for two laps brings disqualification; the starting flag is the host nation's flag and the finish flag is chequered. (How a race meeting works)

Blinky

The racing name for a speed controller running a zero-timing profile in spec-motor classes, so called because an LED blinks when it is armed in neutral. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (A 4.3.1) requires such a controller at spec-motor events: it must not alter the motor's preset timing, must disable boost and turbo functions and follows the motor's sensors one to one. EFRA calls the profile Boost 0, names it the ROAR blinking LEDs mode in its GT12 rules, and allows only controllers on its Approved Blinky ESC list. ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) says its ban on dynamic timing changes applies only in blinky mode. (Speed controllers)

Blocs (IFMAR)

The four continental member organisations through which IFMAR governs, as Wikipedia lists them, each with full voting rights: EFRA (Europe), ROAR (United States and Canada), FEMCA (Asia and Australasia) and FAMAR (South America and South Africa; Wikipedia's FAMAR article adds Mexico and Central America). IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) let the blocs homologate parts such as silencers and bodies for IFMAR use, and each bloc organises World Championships on IFMAR's behalf. AARCMCC is a national member of FEMCA, not a bloc. Wikipedia counts 45 member nations across the blocs; a search summary of another source gave 42 (unconfirmed). (IFMAR and the blocs)

Body shell

The moulded body fitted over a car's chassis. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) requires complete, neatly finished shells securely joined to the chassis whenever a car is on track, never running without a body, with numbers in at least three positions; newly homologated on-road shells carry the part number moulded into the windscreen, and a ready-to-race 1/10 touring car shell must weigh at least 60 g. ROAR's Off-Road Body Announcement (15 January 2025) says that from 2026 every off-road body used at a ROAR-sanctioned event must be on the ROAR Approved List with the maker's part number moulded in. IFMAR's 1/8 IC track World Championship rules (2023 edition) require 1/8 bodies homologated by a bloc up to four months before the event and weighing at least 145 g. (Tyres and bodies)

BRCA

The British Radio Car Association, which calls itself the UK's governing body for RC car racing, covering circuit (on-road), off-road, oval, drifting, large scale and bike disciplines. Its 2026 membership types are Adult (over 16), Junior (under 16) and Non-Driving, by calendar year, and its join page says driving memberships carry BRCA membership insurance for racing at club and BRCA-sanctioned events; a 2026 regional series page instead defines junior entries as drivers aged 16 and under. Wikipedia says the BRCA was founded in 1971 by Ted Longshaw and Keith Plested, is based in Stafford and is a member of EFRA. The BRCA's 2026 section rules were not read. (The BRCA and national bodies)

BRCA Academy

The BRCA's training and development programme: two-day events combining classroom sessions, workshops and on-track training and racing, with at most 32 places, aimed particularly at juniors but open to all ages. The BRCA aims for two events a year, scheduled around national races; no 2026 dates were listed on 30 October 2026. (How people learn)

Brushed motor

An electric motor with brushes. No current racing rule book read sets a limit for brushed motors: EFRA and IFMAR homologate only brushless motors for the electric classes covered here (the EFRA Handbook 2026, Appendix 4 (batteries and motors); IFMAR's electric batteries and motors rules (March 2023)). (Motors)

Brushless motor

The motor type EFRA and IFMAR require in their electric classes. the EFRA Handbook 2026, Appendix 4 (batteries and motors) homologates two types, Modified (sensored or sensorless) and Spec (sensored only); EFRA's 2015 AGM agreed to homologate 05-size brushless motors, and listed motors have been required at its European Championship and Grand Prix events from May 2016 (Appendix 4 also gives 1 June 2016). RC Car Action reported that ROAR approved its first brushless motors on 15 February 2008, the Novak SS10.5 and SS13.5 for Super Stock and the SS17.5 for Stock, a claim repeated from the maker's announcement. (Motors)

Buggy

An off-road racing car, raced in 1/10 electric and 1/8 nitro and electric classes. Wikipedia's buggy article dates Kyosho's nitro Peanuts 09 to 1976 and Tamiya's Rough Rider, which it calls the first true off-roader, to 1979, while Motor Sport (July 2017, a Tamiya-linked writer) calls Tamiya's Sand Scorcher the first mass-market off-road RC car; each first is a claim about a maker's product. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) call for bodies representing off-road, desert or trial racing cars. (Off-road arrives)

Bumper

The front buffer on a car, which several rules regulate. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (rule 2.2) require a flexible plastic front bumper with no metal and rounded corners, to limit damage on contact with other cars, marshals or anyone else; IFMAR's 1/8 IC track World Championship rules (2023 edition) limit the bumper to 5 mm ahead of the body; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) makes bumpers optional but bans rigid blade-like ones and sets wire, sheet and foam sizes meant to minimise injury from being hit by a car; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.3.5) require technical inspection to include bumpers. Any injury needs medical care. (Track and rostrum rules)

C

Carpet

An indoor racing surface. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) specifies needle carpet for indoor on-road racing, runs 1/12 indoors on carpet only, lets 1/10 touring cars race on asphalt or carpet and sets minimum ground clearance on carpet (3 mm for 1/12, 5 mm for 1/10); ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) requires shock protectors on off-road cars racing on carpet. IFMAR's 2026 release on moving the ISTC World Championship, as LiveRC reposted it, says most existing 1/12 entrants prefer carpet. (On-road and off-road)

Chassis

The car's frame, carrying the running gear and electronics. IFMAR's electric off-road rules (version of 13 November 2019) allow one car per driver per class, with the chassis marked at technical inspection; EFRA's GT12 rules in the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) require the chassis shape and hole pattern to be homologated and limit chassis metals to brass, steel or aluminium. Each body's class rules set their own length, width, wheelbase and weight limits. (Chassis and scales)

Class IB and Class IC

Flammable-liquid classes in the NIOSH Pocket Guide, given separately for the two chemicals in nitro fuel: methanol is a Class IB flammable liquid (flash point 52 F in the Pocket Guide, 54 F on NIOSH's emergency response card) and nitromethane a Class IC flammable liquid (flash point 95 F). They are hazard classes for each chemical, not a rating of any fuel blend. Any fuel exposure, including swallowing fuel, needs medical care, and a fuel fire is a matter for the fire service. (Fuel hazards)

Control tyre

A single tyre chosen for everyone in a class at an event. IFMAR's electric off-road rules (version of 13 November 2019) use controlled tyres and inserts picked by IFMAR's Electric section from three organiser recommendations, commercially available in all four blocs, with the previous Worlds' supplier ineligible; IFMAR's 1/8 IC track World Championship rules (2023 edition) require a controlled rim and foam tyre handed out in a controlled area; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) uses a single dry-weather control slick, bought from the organiser, at European Championships for its 1/10 touring car section (rule B 7.4.2 names no class, so it covers touring, front-wheel-drive and Formula One cars) and an organiser-proposed controlled tyre for 1/10 off-road, ratified by the section. (Tyres and bodies)

CPSC

The US Consumer Product Safety Commission, which issues recalls and consumer alerts. Its alert 08-189 (12 February 2008) warned of a fire hazard from lithium batteries in remote-controlled helicopters and airplanes, recording 26 reports since November 2007 of helicopters igniting while being charged; it does not name RC cars. Its staff toy reports place RC cars within NEISS product code 5021, which covers every non-riding toy vehicle. RC recalls are listed by notice number on the battery fire risk and recalls pages. A burning or smoking lithium battery is a matter for the fire service, and anyone hurt needs medical care. (Battery fire risk)

Crystal transmitter

A fixed-frequency transmitter whose channel is set by a crystal, the older alternative to 2.4 GHz. IFMAR's 1/8 IC off-road rules (2024) allow 2.4 GHz DSM/DSS systems or standard crystal transmitters on frequencies authorised in the host country, and in the United States 47 CFR 95.787 (the FCC's rule, Cornell's Legal Information Institute copy) requires plug-in crystals in 72 and 75 MHz transmitters not to be user-accessible. The NZRCS 2026 rule book lists permitted crystal frequencies in the 27, 29, 35, 36, 40 and 72 MHz ranges and bans 75 MHz; New Zealand's regulator text was not read. Racing rules are not law. (Radios and receivers)

D

Drifting (electric)

A discipline IFMAR calls electric drift. IFMAR has published provisional drift rules (2018; seen by title only, unconfirmed), and Wikipedia's IFMAR navigation lists 1:10 electric drifting World Championships in 2020 and 2022 (no IFMAR document confirming them was read, so unconfirmed). The BRCA lists drifting among its disciplines. (Touring cars and new classes)

Driver aids

Electronic help with steering, traction or suspension, which the rule books read ban. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (rule 2.8) forbid traction control, active suspension and gyro- or G-sensor-aided steering, allowing sensors only for passive data recording, because the World Championship is meant to test driver skill; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) bans automated steering, gyroscopes controlling car movement, traction control and active suspension, and allows no signal from the car other than the lap-counting transponder's; IFMAR's electric off-road rules (version of 13 November 2019) also ban active telemetry. (Chassis and scales)

Driver-to-pit radio

Radio between a driver on the rostrum and the pit crew, which the rule books regulate differently. IFMAR's 1/10 IC track World Championship rules (2024 edition) allow driver-to-mechanic radio only on designated public service bands at no more than 500 mW through a single earpiece, and ban 2.4 GHz equipment for it; IFMAR's electric off-road rules (version of 13 November 2019) and the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (A 5.10) ban advantageous driver-to-pit communication during heats and finals, while EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (8.6.2.b) allow driver-to-mechanic radio at certain classes on public service bands at 500 mW with a single earpiece and no 2.4 GHz equipment. (Radios and receivers)

E

EFRA

The European Federation of Radio Operated Model Automobiles, IFMAR's bloc for Europe, whose members are the national governing bodies of European countries and whose rule changes are voted by the national federations at its AGM. EFRA dates its own founding two ways: its 2024 handbook says it was established in 1973, an EFRA article of 18 March 2021 says it has led organised RC motorsport in Europe since 1976, and an article of 12 April 2021 tells the 1973 founding as a legend. Its founding members are also counted two ways: that 2021 article names five federations (Italy, France, Switzerland, Germany and the former Yugoslavia), while Wikipedia says EFRA was formed in May 1973 with six, adding the Netherlands. Its sections cover 1/8 buggy, large scale, IC track and the electric classes. (EFRA)

EFRA Handbook

EFRA's annual rule book, published as a Members Handbook in parts: General Rules and appendices for 1/8 and 1/10 track (1), 1/8 off-road (2), electric cars (3), electric motor and battery rules (4), large scale (5), homologation and registration (8) and body homologation (9). This site read the 2026 Appendices 3, 4 and 8 and the 2024 General Rules; the 2026 General Rules and Appendices 1, 2 and 5 were not read. (EFRA)

EFRA registration

EFRA's International Drivers Registration, needed for its European and World Championship entries. Under EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (section 4), a driver's national federation approves the registration on the EFRA website for one calendar year ending 31 December, the number is personal, entries go through the federation, and drivers at EFRA Grand Prix and other sanctioned events need their national licence where one exists. Search summaries of EFRA handbook files say EFRA issued A and B licences in 2009 and moved to federation-approved registration from 2019 (unconfirmed). (EFRA)

Electric

Cars powered by a battery and an electric motor, one of the two power sources in the bodies' structures. IFMAR has an Electric section alongside its IC section, each with a chairman (IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024); IFMAR's electric off-road rules (version of 13 November 2019)), and EFRA's electric classes are governed by Appendices 3 and 4 of its handbook. Wikipedia describes an electric car's motor power as regulated by an electronic speed controller. (Electric and nitro)

ESC (electronic speed controller)

The electronic unit that controls the drive motor. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) allows any ESC that does not interfere with lap counting, computers or transmitters, kept inside the car and not protruding through the shell, permits current or voltage limiters and a passive data recorder adjusted only while the car is stationary, and requires blinky controllers in spec classes; IFMAR's electric off-road rules (version of 13 November 2019) allow any mechanical or electronic speed controller; ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) requires the most recent ROAR-approved firmware and bans beta software. (Speed controllers)

EU Regulation 2019/1148

The European Union's regulation on the marketing and use of explosives precursors (European Parliament and Council, 20 June 2019), which covers nitromethane. Estonia's Ministry of Economic Affairs says that under it, from 1 February 2021, nitromethane above 16 percent by weight is restricted, so private individuals may not acquire, bring in, possess or use it; a Red RC report of 5 October 2023 on a European Parliament petition supported by EFRA describes the change for model drivers as a cut from 25 percent to 12 percent, a figure found in no regulator's text (unconfirmed). The regulation's Annex I was not read, and IFMAR's 25 percent limit is by volume while the 16 percent threshold is by weight, so the numbers are not directly comparable. Racing rules are not law. (Nitro fuel rules)

European Championship (EC)

EFRA's continental title events. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) let each section run up to four European Championships a year at venues decided by the AGM, alongside one official EFRA Grand Prix per member country per section; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) runs an electric European Championship in every year with no World Championship for that class in Europe and bars EC entrants from the chosen track for 21 days before. EFRA posted on 25 September 2026 that no official 2026 European Championship was held in Large Scale Touring Car or F1 because the EFRA bloc hosted the Large Scale World Championship. (EFRA European Championships 2026)

Exhibition final

A non-championship final for a particular group of drivers. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) schedule an exhibition final for drivers over 45 at the 1/8 IC off-road World Championship; the minutes of EFRA's 1/8 off-road section meeting of 8 November 2025 made EFRA's 1/8 off-road 40+ exhibition final optional, and EFRA's 2026 calendar in those minutes lists a separate Masters 40+ European Championship. (How a race meeting works)

F

FAMAR

IFMAR's fourth bloc. Wikipedia describes FAMAR as the bloc for South Africa, Mexico, Central America and South America, founded in 1992 and one of IFMAR's four voting blocs, with 16 member countries listed and results tables ending in 2017; Wikipedia's IFMAR article calls it the newest bloc. No FAMAR page or FAMAR rule book was read, and the 2026 South American Championships result is not attributed to FAMAR because the report read names no organising body. (IFMAR and the blocs)

FCC

The US Federal Communications Commission, which writes the Radio Control Radio Service rules in 47 CFR Part 95, Subpart C (sections include 95.731 on permissible use, 95.733 on prohibited use, 95.763 on channel frequencies and 95.787 on additional requirements) and the Part 15 rules for unlicensed devices. Under 95.733, Radio Control Radio Service transmitters may not send data (identifying tones aside) or voice and may not be used commercially; they may carry only messages that operate remote devices. The FCC's own page on the service returned an error, so this site reads the rules as published by Cornell's Legal Information Institute. ROAR's National Guidelines (revised 13 October 2026) allow only frequencies the FCC permits at ROAR Nationals. Racing rules are not law. (Radio rules by country)

FEMCA

The Far East Model Car Association, IFMAR's bloc for Asia and Australasia. Wikipedia says it was founded in 1980 in Hong Kong and, after two false starts, re-established in 1985, when it hosted its first IFMAR race in Tokyo. Its size is reported two ways: Red RC (17 November 2025) says FEMCA represents 15 nations, while Wikipedia's member table lists 16 national bodies, among them AARCMCC (Australia) and JMRCA (Japan). No FEMCA rule book or FEMCA web page was found. (IFMAR and the blocs)

First RC car

No source settles which radio-controlled model car was the first, and no account rests on a primary document read. Four versions are recorded: El-Gi of Reggio Emilia, Italy, with 1:12 radio-controlled Ferraris on sale by mid-1966 (Collectors Weekly; a forum member cites a June 1966 issue of Quattroruote); Mardave of the UK, named in a December 2006 version of Wikipedia's article and disputed in April 2007, according to historian David Palmeter; RE-EL, another Reggio Emilia maker, whose own claim for its Ferrari P5 is known only second-hand from a forum; and Testors of the United States, which announced an electric radio-controlled Mustang in February 1966, as Palmeter's site records from contemporary magazines. Each maker's first is a claim. Wikipedia says radio-controlled cars have existed since the 1940s without naming a first, and EBSCO says hobbyists made the first RC cars in the early 1960s from model aircraft engines. (The first RC cars)

First world championship

Which race was the first world championship for RC cars is disputed. IFMAR's own history lists a 1/8 IC track race at Pomona in 1977 and an event in Geneva in 1979 as events, and calls the 1981 Indianapolis race its first championship, with which Red RC agrees; Wikipedia calls the 1977 Pomona race the inaugural 1:8 IC track World Championship. The 1977 race predates IFMAR, which says it was inaugurated in 1979. IFMAR dates its first electric World Championship, for 1/12, to 1982. (The world championships)

First-aid officer

An official named in race safety rules, which the bodies require differently. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (rule 3.8.g) require a first-aid officer present throughout a World Championship, with access for police and emergency services to all areas, while EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.3.7) say a first-aid officer should be present at events attracting large crowds; each rule applies only to its own body's events. Any injury needs medical care. (Track and rostrum rules)

Flying start

A start in which timing begins as each car first crosses the line, also called a rolling start. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) start each car's timing on its first pass of the start line in qualifying, and IFMAR's 1/8 GT and GTE rules (2025 edition) run 7-minute GT heats with a rolling start after a 3-minute warm-up. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) uses a staggered start for electric qualifying instead. (How a race meeting works)

G

Glow plug

A plug in model nitro engines, named in IFMAR's engine rules: IFMAR's 1/10 IC track World Championship rules (2024 edition) allow glow plug ignition only in the 200 mm nitro touring car, with air-cooled two-stroke engines of at most 2.11 cc. No rule read describes the plug further, and this site gives nothing on running engines. (Nitro engines and mufflers)

Grand Prix (EFRA)

EFRA's sanctioned international events below the European Championships. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) allow one official EFRA Grand Prix per member country per section, and drivers at Grand Prix events need their national licence where one exists; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) lets any commercially available 1/10 off-road wheels and tyres be used at Grand Prix events, and EFRA requires homologated motors at its electric European Championship and Grand Prix events. (EFRA European Championships 2026)

GT12

EFRA's 1/12 GT class with replica GT bodies. EFRA describes GT12 as an entry-level class: its GT12 rules in the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (part C) set a minimum weight of 950 g ready to race with transponder, a rolling chassis at most 165 mm wide, a wheelbase of 196 to 208 mm, a homologated chassis, batteries only from EFRA's 1S Stick Lithium Battery Homologation List at no more than 3.8 V nominal, and a blinky controller in the ROAR blinking LEDs mode. Part B of the same appendix (B 6) sets out a separate 1/12 GT 17.5 class that also uses GT12 bodyshells, with 17.5T spec motors and a minimum of 790 g with body and transponder, so the 950 g and 790 g figures belong to two different classes. ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) requires GT12 bodies to resemble full-scale GT2 and GT3 racing cars, with LMP and LMH bodies prohibited. (The classes)

H

Hard case

The factory-sealed protective case EFRA and IFMAR require around lithium racing packs. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (1.1) requires a case of ABS or similar completely enclosing the cells, factory sealed so that opening it destroys it, cuboid, with openings only for leads or connectors, and (1.2) maximum sizes including plugs of 93.0 x 47.0 x 18.5 mm for 1S, 139.0 x 47.0 x 25.1 mm for 2S and 139.0 x 47.0 x 48.2 mm for 4S; IFMAR's electric batteries and motors rules (March 2023) set the same case rule and the same 1S and 2S sizes. ROAR's 2011 rules, as LiveRC reprinted them, also required a hard case with a ROAR Approved label across the seam. The case is a rule requirement; this site does not present it as a safety device. (Batteries)

Heat

A timed qualifying race. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) allow at most 12 drivers per heat, at most 10 minutes plus the last lap, and up to six qualifying attempts per driver; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) sets heats of 8 minutes for 1/12 and 5 minutes for 1/10 off-road and on-road, each plus the time to finish the last lap; ROAR's National Guidelines (revised 13 October 2026) cap electric off-road Nationals at 30 qualifying heats of at most 10 cars. (How a race meeting works)

Heating and cooling ban

A battery and tyre rule. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (2.5) bans any added heating of a battery and any cooling devices or freeze sprays, and IFMAR's electric batteries and motors rules (March 2023) ban heating or cooling batteries, freeze sprays included; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) bans heating controlled touring car tyres other than with permitted tyre warmers and bans tyre warmers at all EFRA 1/10 off-road events, and IFMAR's electric off-road rules (version of 13 November 2019) ban tyre warmers. (Battery rules at events)

Homologation

Formal approval of a part by a body for use at its events. EFRA homologates motors, batteries and bodies, and now speaks of registration rather than homologation for mufflers so that a listed muffler is not taken as always acceptable (the EFRA Handbook 2026, Appendix 8 (mufflers); the EFRA Handbook 2026, Appendix 4 (batteries and motors)); IFMAR approves 05 motors after checks by a testing laboratory (IFMAR's electric batteries and motors rules (March 2023)) and lets the blocs homologate silencers and bodies for IFMAR use (IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024)). A homologation by one body applies to that body's events. (Approved equipment lists)

HSE nitromethane report (March 2026)

A technical report by the HSE, acting as Great Britain's CLP Agency, on classifying nitromethane. It concludes that nitromethane meets the criteria for Acute Toxicity 4 (harmful if swallowed or inhaled), STOT RE 2, Carcinogenicity 1B and Reproductive Toxicity 1B, in agreement with the opinion of the ECHA's Committee for Risk Assessment, and says this classification had not yet been agreed or adopted in Great Britain when it was published; the existing Flammable Liquid 3 classification stays. Any fuel exposure, including swallowing fuel, needs medical care, and a fuel fire is a matter for the fire service. (Fuel hazards)

I

IC (internal combustion)

IFMAR's term for engine-powered classes; IFMAR has an IC section with its own chairman and executive (IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024)). IFMAR's IC World Championship classes include 1/8 off-road, 1/8 track, 1/10 track, 1/8 GT and 1/5 track; its fuel rules for the 1/8 and 1/10 IC classes allow methanol and/or ethanol with oil and a set share of nitromethane (IFMAR's 1/10 IC track World Championship rules (2024 edition)). The BRCA's Large Scale Off Road series uses petrol engines of 23 to 32 cc. (Electric and nitro)

IFMAR

The International Federation of Model Auto Racing, the world body for RC car racing, which governs through four blocs and publishes a separate World Championship rule book for each discipline, each read with its General Rules (which this site's research did not find). IFMAR says it was officially inaugurated in 1979 with Ted Longshaw of Great Britain as the driving force and first president (Wikipedia gives 9 July 1979); its seat moved to Australia in 1995, it was de-registered there in 2006, leaving it without a legal entity, and the Belgian government published it as an international non-profit association on 15 October 2018. (IFMAR and the blocs)

Impound (transmitter impound)

The holding of drivers' transmitters by officials during an event. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (8.6.7) require a place next to the rostrum for transmitters while drivers marshal when transmitter impound is not compulsory; IFMAR's 1/10 IC track World Championship rules (2024 edition) say no radio impound is needed because about 99 percent of drivers use 2.4 GHz, but radios may be switched on only for the running heat and the next group, and the race director can reinstate impound after complaints from at least three countries; ROAR's National Guidelines (revised 13 October 2026) leave radio impound to the Race Management Team. (Radios and receivers)

Inlet noise silencer (INS box)

A homologated silencer box on a nitro engine's air intake. IFMAR's 1/8 IC track World Championship rules (2023 edition) require homologated INS boxes with homologated mufflers, and the 85 dB limit at 10 m applies to a muffler with its INS box; the EFRA Handbook 2026, Appendix 8 (mufflers) requires every engine to have an exhaust system and an inlet silencer, bars changes to an INS box's dimensions and lists approved boxes on EFRA's website. (Nitro engines and mufflers)

Insurance

Cover that racing bodies require or provide, stated here without amounts. EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.3.9) make public liability insurance compulsory for all EFRA events, covering all competitors and officials; IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (3.8.i) make insurance against accidents and liability compulsory for World Championships; the BRCA says its memberships carry membership insurance for racing at club and BRCA-sanctioned events and that club affiliation in 2026 includes public liability insurance covering competitors and organisers; ROAR says its members are insured at any ROAR-sanctioned event. (Insurance)

International Jury

IFMAR's panel for protests at World Championships. Under IFMAR's electric off-road rules (version of 13 November 2019), an International Jury of official representatives of the blocs, chaired by the IFMAR section chairman, rules by simple majority on protests outside the race director's remit and on stopping racing for weather. (Marshalling and officials)

IR 2030 (UK)

The UK Interface Requirement 2030 for licence-exempt short range devices. Under the Wireless Telegraphy (Exemption) Regulations 2021 (SI 2021/493, made by Ofcom and in force from 12 May 2021), short range devices are exempt from licensing under section 8(1) of the Wireless Telegraphy Act 2006 if they comply with IR 2030, cause no undue interference and are not used airborne unless the IR allows it; SI 2026/396 (29 April 2026) switched the reference to the April 2026 edition of IR 2030. The IR 2030 model-control band list could not be read because Ofcom's pages returned errors, so the bands given in search summaries are unconfirmed. (Radio rules by country)

ISED RSS-210 (Canada)

Canada's standard for licence-exempt radio apparatus. ISED's Notice 2024-DRS0007 (25 June 2024) announced RSS-210 Issue 11, Licence-Exempt Radio Apparatus: Category I Equipment, whose scope includes remote control devices; the notice does not mention model control, and no ISED page setting Canadian model-car frequencies was read. (Radio rules by country)

J

JMRCA

The Japan Model Racing Car Association, Japan's FEMCA member. Wikipedia dates its founding two ways: its JMRCA article's text says February 1971, while that article's infobox and Wikipedia's FEMCA member table give 1974. Wikipedia also says JMRCA held its first championship in 1978, for 1:8 pan cars (unconfirmed). (The BRCA and national bodies)

Junior and youth classes

Age-based classes and titles, defined separately by each body; no minimum racing age was found in any body's document read. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) schedule a youth final for drivers aged 15 and under; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) give an award to the best driver under 17, with age taken on 1 January, and the minutes of EFRA's 1/8 off-road section meeting of 8 November 2025 make the under-17 final winner junior European Champion if no under-17 driver reaches the semi-finals and main final; the BRCA's membership page defines Junior as under 16, while its join page and a 2026 regional series page say 16 and under; NZRCS takes age on the day of the event for its under-16 titles. (Youth and junior rules)

K

Kv

A motor rating in revolutions per minute per volt, used by makers. RC Car Action (2016, trade press) describes Kv as a motor's unloaded rpm per volt, says actual rpm under load is lower, and says makers indicate a motor's level by either turns or Kv depending on brand. No rule book read sets a Kv limit: EFRA and IFMAR define spec motors by turns and winding instead (the EFRA Handbook 2026, Appendix 4 (batteries and motors); IFMAR's electric batteries and motors rules (March 2023)). (Motors)

L

Ladder finals

A finals system, also called a Christmas tree, in which every driver gets a final and the top finishers of each lower final move up. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) seed odd-placed qualifiers into an A series and even-placed into a B series, move the top three or four of each sub-final up, run lower sub-finals of 20 minutes and 30-minute finals from the eighth-finals to the semi-finals, and end with a 60-minute main final of 11 or 13 cars; the minutes of EFRA's 1/8 off-road section meeting of 8 November 2025 amended EFRA's 1/8 off-road ladder to 12-car finals with four moving up from each sub-final and six from each semi-final; ROAR's National Guidelines (revised 13 October 2026) say ROAR has adopted IFMAR-style ladder mains for fuel classes, though the number of drivers in a final may vary. (How a race meeting works)

Last-chance qualifier (LCQ)

A short race that sends one more driver into the main final. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) include the winner of a 15-minute last-chance qualifier among the 11 or 13 main-final cars, and EFRA's amended 1/8 off-road finals rule adds a 13th car from a 15-minute last-chance race (the minutes of EFRA's 1/8 off-road section meeting of 8 November 2025). (How a race meeting works)

Licence (racing)

A national body's permission to race, defined by each body. NZRCS requires drivers at its sanctioned meetings to hold an NZRCA National Racing Licence; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) require a valid national licence at EFRA Grand Prix and other sanctioned events where one exists, and use federation-approved registration for European and World Championships; the BRCA's join page calls its junior membership the BRCA U16 Licence. (How people learn)

LiFe

The second lithium chemistry EFRA and IFMAR approve for racing packs, alongside LiPo. Under the EFRA Handbook 2026, Appendix 4 (batteries and motors), LiFe cells are rated at no more than 3.3 V nominal, giving 6.6 V for a 2S pack and 13.2 V for 4S, with charged limits of 3.70 V for 1S, 7.40 V for 2S and 14.80 V for 4S; IFMAR's electric batteries and motors rules (March 2023) use the same 3.3 V and 6.6 V nominal figures and cap a 2S LiFe pack at 7.40 V, and the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) sets the 6.6 V limit for EFRA's 1/10 classes. (Batteries)

LiPo

Lithium polymer, one of the two lithium chemistries (with LiFe) that EFRA and IFMAR approve for racing packs. the EFRA Handbook 2026, Appendix 4 (batteries and motors) says EFRA has homologated only lithium-based batteries since 2009, and EFRA's battery homologation officer wrote on 28 October 2011 that deleting the NiCd and NiMH rules was proposed for that year's AGM; IFMAR's electric batteries and motors rules (March 2023) approve only lithium-based batteries; Red RC reported on 16 January 2008 that ROAR had reversed an earlier ban and approved LiPo packs under rule 8.3.2. LiPo cells are rated at no more than 3.8 V nominal and capped at 4.20 V charged at EFRA and IFMAR events. IATA's 2026 passenger guidance never names lithium polymer. (Batteries)

LiPo sack

A receptacle racing rules require around lithium packs on charge, defined in those rules as designed for charging and built to contain a LiPo or LiFe fire; that definition is the rules' wording, not a test result, and this site does not claim a sack stops or holds a fire. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (2.4) and the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (A 3.4) require drive batteries to be in a sack whenever charged or discharged (except in a race or on organiser resistors), while EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.3.12) apply it to all racing, car and radio batteries on charge; IFMAR's electric batteries and motors rules (March 2023) (3.11) speak of charging only, and IFMAR's 1/8 e-buggy rules (April 2023) say charged or discharged. ROAR's 2008 LiPo rule, as Red RC reproduced it, also required one when charging. A burning or smoking lithium battery is a matter for the fire service, and anyone hurt needs medical care. (Battery rules at events)

LMP (1/12)

EFRA's 1/12 prototype sports car class, divided into Modified and Spec 13.5T, beside a lower-powered GT 17.5 class that EFRA describes as intended for beginners and senior drivers. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) gives LMP a maximum width of 172 mm without the shell and a minimum weight of 730 g (B 6.2), and bars drivers who reached an A-final in LMP Modified or Spec 13.5T at a World, European or national championship in the previous season from GT 17.5. ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) prohibits LMP and LMH bodies in GT12. (The classes)

M

Main final

The deciding race of a meeting. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) run a 60-minute main final of 11 or 13 cars at the 1/8 IC off-road World Championship, with drivers choosing rostrum positions in qualifying order; IFMAR's 1/8 IC track World Championship rules (2023 edition) and IFMAR's 1/10 IC track World Championship rules (2024 edition) send the top qualifier and the Super Pole winner straight into a 60-minute main final; the minutes of EFRA's 1/8 off-road section meeting of 8 November 2025 set EFRA's 1/8 off-road main final at 45 or 60 minutes. (How a race meeting works)

Marshal

A person who recovers crashed cars on the track during a race; under the rules read, competitors do it. IFMAR's electric off-road rules (version of 13 November 2019) have the drivers of each heat take marshal positions for the next heat, with two organiser fill-in marshals and exceptions for very young or physically disabled drivers after consulting the race director; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (8.15) say only drivers taking part may and must marshal the heat after their own, require each marshal position to be furnished with gloves or other protection and a safety jacket that is compulsory to wear, and penalise failure to marshal; the BRCA's October 2025 Large Scale Off-Road briefing required hi-vis vests and gloves and allowed no one under 14 to marshal. (Marshalling and officials)

Methanol

One of the two chemicals in model nitro fuel; IFMAR's fuel rules allow methanol and/or ethanol (IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024)). NIOSH's Pocket Guide calls methanol (wood alcohol) a Class IB flammable liquid, lists the eyes, skin, respiratory system, central nervous system and gastrointestinal tract among target organs and visual disturbance and optic nerve damage among symptoms, and gives a flash point of 52 F, where NIOSH's emergency response card gives 54 F; the card says symptoms can be delayed 1 to 72 hours, that its metabolites can cause metabolic acidosis, blindness and death, and that its odour is no reliable warning. A volunteer fire department, as trade press reported, says methanol can burn with almost undetectable flames in daylight; that is a full-size racing report, unconfirmed as a regulator statement. Any fuel exposure, including swallowing fuel, needs medical care, and a fuel fire is a matter for the fire service. (Fuel hazards)

Modified

The open motor class in electric racing. the EFRA Handbook 2026, Appendix 4 (batteries and motors) and IFMAR's electric batteries and motors rules (March 2023) set no turn limit for Modified 05 motors (classes may set a minimum) and allow delta or Y windings, with EFRA allowing sensored or sensorless motors; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) requires motors of no less than 6.5 turns in its 1/12 Modified class. ROAR's National Guidelines (revised 13 October 2026) let a driver race only one level below their highest class, so a 21.5 entrant may not also enter Modified. (Motors)

Muffler

The exhaust silencer on a nitro engine, which IFMAR and EFRA control by list. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) allow only IFMAR-homologated silencers carrying their number, homologated by a bloc up to four months before an event; IFMAR's 1/8 IC track World Championship rules (2023 edition) require mufflers of at least three chambers with a straight circular outlet pointing level or downward, at most 85 dB at 10 m with the inlet silencer; the EFRA Handbook 2026, Appendix 8 (mufflers) allows only EFRA-registered mufflers (three chambers for 1/8 track, 1/8 off-road and GT8, two for 1/10 IC track) with the number engraved, registered for two years. (Nitro engines and mufflers)

N

Nationals (ROAR)

ROAR's national championships, its Level 5 events, run separately by surface and class. ROAR's National Guidelines (revised 13 October 2026) say a Race Management Team contracted by ROAR runs them, require full-year ROAR membership, cap electric on-road at 25 and electric off-road at 30 qualifying heats of at most 10 cars, run four electric qualifying rounds over two days with mains on day three, and use IFMAR-style ladder mains in fuel classes. The first ROAR National Championship is dated 1968 at Garden Grove, California, by Wikipedia and 1969 by an Axial blog post, a maker's claim; no ROAR document settles it. (ROAR Nationals 2026)

NEISS code 5021

The US injury-surveillance product code that covers RC cars along with every other non-riding toy vehicle; NEISS has no RC-car code. CPSC staff estimated 10,700 injuries seen in US hospital emergency departments for the category in 2023 (all ages) and 13,400 in 2014, but the two reports use different age bands, so the figures are separate estimates and not a trend, and the CPSC says a toy linked to an injury was not necessarily its cause. No injury study specific to RC car racing was found. Any injury needs medical care. (Injury data)

NiCd and NiMH

Nickel-cadmium and nickel-metal hydride, the cell types raced before lithium. Palmeter's site says the 1966 Testors Mustang ran on rechargeable NiCd cells (unconfirmed, and a maker's product, not a confirmed claim); Motor Sport (July 2017, a Tamiya-linked writer) says Tamiya's first RC car first ran on dry cells before Tamiya developed NiCd packs that became an industry standard, a claim; Wikipedia says NiCd cells powered off-road racing from the early 1980s until NiMH replaced them. LiveRC says ROAR's 1978 1/12 classes were split into 6-cell and 4-cell divisions (single report, unconfirmed), and EFRA's battery homologation officer wrote on 28 October 2011 that competitors no longer used NiCd or NiMH. (Motors and batteries history)

NIOSH

The US National Institute for Occupational Safety and Health, whose Pocket Guide and emergency response card are, with the HSE, this site's sources for the hazards of methanol and nitromethane. Its exposure limits are workplace limits, not hobby guidance: for methanol, a recommended limit of 200 ppm (time-weighted average) and 250 ppm (short term); for nitromethane, no NIOSH recommended limit, with the OSHA limit given in the Pocket Guide as 100 ppm. Any fuel exposure, including swallowing fuel, needs medical care, and a fuel fire is a matter for the fire service. (Fuel hazards)

Nitro

The common name for model engines and their fuel. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) allow nitro fuel of only methanol and/or ethanol, lubricating oil, a little anti-corrosion additive and at most 25 percent nitromethane by volume, and IFMAR's 1/10 IC track World Championship rules (2024 edition) cap nitromethane at 16 percent; Wikipedia describes nitro cars as having a small combustion engine. This site gives the hazards of methanol and nitromethane separately, as NIOSH and the HSE publish them, never as one rating for a blend. (Nitro fuel rules)

Nitromethane

The other chemical in model nitro fuel, limited by IFMAR to 25 percent by volume in its 1/8 IC off-road and track rules and 16 percent in its 1/10 IC track and 1/8 GT rules. NIOSH's Pocket Guide calls it a colourless oily Class IC flammable liquid (flash point 95 F) whose target organs include the eyes, skin, central nervous system and liver, with no NIOSH recommended exposure limit; the HSE's March 2026 report concludes it meets the criteria for Acute Toxicity 4, STOT RE 2, Carcinogenicity 1B and Reproductive Toxicity 1B, a classification not yet agreed or adopted in Great Britain. Case reports in BMJ Case Reports (2017) and NDT Plus (2007) describe adults who swallowed model-engine fuel, in whom nitromethane falsely raised a creatinine test, and Emergency Medicine (2017) describes a toddler who sipped a model race car fuel additive. Any fuel exposure, including swallowing fuel, needs medical care, and a fuel fire is a matter for the fire service. (Fuel hazards)

Noise trap (EFRA)

EFRA's on-track noise check: under the EFRA Handbook 2026, Appendix 8 (mufflers), sections use a noise trap, depending on the track layout, to take out cars that make too much noise, set each event's final noise limit before timed practice, and say EFRA's definition of a noise level is final. The BRCA's October 2025 Large Scale Off-Road briefing listed sound-level checks among its random scrutineering. (Noise and mufflers)

NZRCS and NZRCA

New Zealand's oval-racing rule body and its national association. The NZRCS 2026 rule book (version 1.2, July 2026) covers 1/10 electric oval classes, split into contact classes (Superstocks, Stockcars, Streetstocks) and non-contact classes (Saloon Cars, Modifieds), requires an NZRCA National Racing Licence at sanctioned meetings, takes effect each 1 January after a remit process, and requires 2.4 GHz (or DSM) radios as a body rule. Wikipedia's FEMCA table lists NZRCA as New Zealand's FEMCA member. (The BRCA and national bodies)

O

Ofcom

The UK communications regulator, which made the Wireless Telegraphy (Exemption) Regulations 2021 (SI 2021/493), under which short range devices complying with IR 2030 need no licence. Every Ofcom page tried returned an error; a search summary of Ofcom's radio-controlled models page says IR 2030 governs model control and that using non-compliant equipment is an offence under the Wireless Telegraphy Act (unconfirmed). (Radio rules by country)

Off-road

Racing on rough tracks with jumps, as opposed to flat on-road circuits. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) allows 1/10 off-road tracks at least 3 m wide and at most 250 m long; IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) put the safety of the public and marshals first in jump design; Wikipedia distinguishes off-road cars for rough terrain from on-road cars for flat surfaces. (On-road and off-road)

On-road

Racing on flat circuits, on carpet or asphalt. EFRA's electric on-road classes are 1/12, 1/10 touring car, Formula One and front-wheel drive (the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4)), and IFMAR's IC track classes include 1/8, 1/10 and 1/8 GT (IFMAR's 1/8 IC track World Championship rules (2023 edition)); the BRCA calls on-road racing circuit. (On-road and off-road)

Oval

Racing on an oval track, run by some national bodies. The NZRCS 2026 rule book covers 1/10 electric oval classes in contact and non-contact groups, the BRCA lists oval among its disciplines, and Wikipedia's BRCA article lists a 1/12 carpet oval section. (On-road and off-road)

P

Pan car

A car built on a flat pan chassis. LiveRC (2014) says the first 1/12 pan cars appeared in the late 1970s with a flat fibreglass pan chassis, and calls 1/12 IFMAR's oldest electric class; Wikipedia says the first ROAR National Championship, which it dates to 1968 (an Axial blog post gives 1969, a maker's claim), was for 1/8 scale nitro pan cars, and that JMRCA's first championship, in 1978, was for 1:8 pan cars (unconfirmed). (Early racing and ROAR)

Parc ferme

A secure area where cars are held for inspection. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (3.27) send semi-finalist and finalist cars to parc ferme for inspection straight after their race, and IFMAR's 1/8 IC track World Championship rules (2023 edition) impound cars at the end of the finals for checks of engine size and tank capacity. (How a race meeting works)

Q

Qualifying

The heats that rank drivers for the finals, scored differently by each body. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) give the fastest driver in each round 0 points, second 2, third 3 and so on, 500 to a driver who does not score, and count each driver's best three of six rounds; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) uses a round-by-round system ranking every driver against all others in each round, counting 2 of 3, 4 or 5 rounds and 3 of 6; IFMAR's electric off-road rules (version of 13 November 2019) count the best three of five rounds; ROAR's National Guidelines (revised 13 October 2026) run four electric rounds with a re-sort after two. (How a race meeting works)

R

Race director

The official in charge of a meeting under each body's rules. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) gives EFRA's race director absolute authority at the meeting and lets them assign rostrum positions; IFMAR's electric off-road rules (version of 13 November 2019) require IFMAR's race director to be approved by IFMAR and the host bloc, managing tasks including marshalling and protests, with an International Jury above; ROAR's National Guidelines (revised 13 October 2026) have the Race Management Team supply the race director, who can make immediate judgements or penalties and leads the protest committee. (Marshalling and officials)

Radio Control Radio Service (RCRS)

The US radio service for remote control in 47 CFR Part 95, Subpart C (the FCC's rules, read on Cornell's Legal Information Institute because fcc.gov could not be read). Under 95.305 eligible people may operate Part 95 stations without an individual licence; 95.763 lists channels at 26 to 28 MHz, 72 MHz and 75 MHz, and 95.731 (read only as an unofficial 2017 copy) keeps 72 MHz for model aircraft, 75 MHz for model surface craft and 26 to 28 MHz for any device; 95.733 bars data, voice and commercial use. No FCC text read ties 2.4 GHz car radios to the service. (Radio rules by country)

Radio Equipment Directive (2014/53/EU)

The European Union's framework for making radio equipment available on its market (16 April 2014), read as archived on legislation.gov.uk: it defines radio equipment and sets essential requirements in Article 3 for health and safety, electromagnetic compatibility and efficient use of spectrum. IFMAR's rule books say only that radio gear must be permitted in the host country. Racing rules are not law. (Radio equipment rules)

Rallycross Worlds

The original name, according to Wikipedia, of the IFMAR 1:8 IC off-road World Championship, which Wikipedia says was first held in 1986 at Grenoble, France, and has since run in even years, alternating with the 1/10 electric off-road Worlds; no IFMAR page confirming this was read (unconfirmed). (Off-road arrives)

Recall notice

A regulator's published notice of a product withdrawn for a hazard, given on this site by number and date without the firm's name. RC-related notices from the US CPSC include 17-139 (25 April 2017, ready-to-run 1/10 vehicles whose speed controller can short-circuit, a fire hazard), 13-227 (25 June 2013, LiPo batteries for micro RC vehicles with leads connected to the wrong terminals), 08-318 (1 July 2008, RC vehicles whose remote control could lose its signal) and 04-160 (15 June 2004, chargers for RC race car batteries); the CPSC's 26-379 (2 April 2026) charger notice does not say what batteries the charger is for, so it is not called an RC charger here. The UK's OPSS report 2502-0069 (18 March 2025) concerned a toy RC car rejected at the border for high fire risk. A burning or smoking lithium battery is a matter for the fire service, and anyone hurt needs medical care. (Battery fire risk)

Receiver

The unit in the car that takes the transmitter's signal. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) lets the receiver work steering and motor management but bans using it to capture signals from sensors in the car; IFMAR's electric off-road rules (version of 13 November 2019) allow only two devices on the receiver, normally the steering servo and the speed controller, plus an optional separate battery. (Radios and receivers)

Receiver pack

A separate battery for the receiver and servos, on which EFRA and IFMAR disagree. IFMAR's electric batteries and motors rules (March 2023) (3.15) allow one in 1/12 and 1/10 off-road cars but not in 1/10 touring cars, while the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) allows receiver batteries in 1/12 but not in 1/10 touring, Formula One, front-wheel-drive or 1/10 off-road cars; so for 1/10 off-road, IFMAR allows a receiver pack and EFRA does not. (Battery rules by body)

ROAR

Remotely Operated Auto Racers, IFMAR's bloc for the United States and Canada, which describes itself as a national non-profit corporation originally organised in 1967, covering 12 US regions plus Canada. ROAR claims over 4,500 members aged from under 7 to over 70 and about 200 sanctioned clubs (its 2026 page), sanctions events from club level up but runs only its Level 5 National events itself, and says it is the only organisation authorised to send North American drivers to IFMAR World Championships. ROAR's page lists five appointed Executive Committee members where Wikipedia says seven. ROAR's current rule book was not read. (ROAR)

Rostrum

The raised drivers' stand overlooking the track. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (3.7) call for room for 10 to 12 drivers at 80 cm or more each, a floor 2 to 4 m high, a solid stair, a strong parapet, a weather cover, an equal view for every position and 2 to 4 m to the nearest part of the track; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.2.2) set room for 10 drivers at 80 cm each, a floor 2 to 3 m high as standard, a stair at least 1.20 m wide and a mandatory parapet, and (5.3.10) bar the use of mobile phones on the rostrum; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) keeps drivers off it until race control declares the previous race over. (Track and rostrum rules)

S

Safeguarding

Policies on the welfare of children, young people and members in a racing body; the only one found is the BRCA's. The BRCA's safeguarding page summarises its 2024 Safeguarding Policy, names a designated Safeguarding Officer, states zero tolerance of abuse or neglect towards members, children or young people, and commits to clear channels for raising concerns. No safeguarding policy was found for EFRA, IFMAR, ROAR or AARCMCC, which is not the same as none existing. (Safeguarding)

Scale

The size of a model against a full-size car, written as a fraction; with power source and surface, scale defines the class. The classes in the rule books read are 1/5 (large scale), 1/8, 1/10 and 1/12 (IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024); IFMAR's electric off-road rules (version of 13 November 2019)), and Wikipedia's BRCA article also lists a 1/18 micro car section. The EBSCO Research Starter (2022) says most early RC cars of the late 1960s were 1:8 scale. (Chassis and scales)

Sensored motor

A brushless motor with a sensor connection to its speed controller, as the rules define it. the EFRA Handbook 2026, Appendix 4 (batteries and motors) requires spec motors to be sensored, lets Modified motors be sensored or sensorless, and fixes a six-position JST ZH sensor connector with a set pin order that includes a 10K thermistor line; IFMAR's electric batteries and motors rules (March 2023) name the same six-position JST header for speed controllers that work with sensored motors. (Motors)

Servo

An actuator worked by the receiver, normally for steering. IFMAR's electric off-road rules (version of 13 November 2019) allow at most two control devices (two servos, or a servo and a speed controller), and IFMAR's 1/8 IC track World Championship rules (2023 edition) ban more than two servos. (Radios and receivers)

Spec class

A motor class in which the motor's turns are fixed. the EFRA Handbook 2026, Appendix 4 (batteries and motors) (4.13 to 4.17) requires spec motors to be sensored and Y-wound with fixed turns and wire diameters, with the wind number etched on motors introduced from 2011, and lists 21.5T, 17.5T, 13.5T and 10.5T; IFMAR's electric batteries and motors rules (March 2023) list 13.5T, 17.5T, 21.5T and 25.5T, so the two bodies' lists differ. Spec classes at EFRA events need a blinky speed controller, and ROAR's National Guidelines (revised 13 October 2026) bar a driver who reached an A main at an IFMAR Worlds in the previous five years from the slowest spec class at a National. (Motors)

Spread spectrum (FHSS and DSSS)

The radio techniques 2.4 GHz model systems use. Model Aviation (February 2015, written for aircraft) says RC radios use frequency hopping (FHSS), direct sequence (DSSS) or both: Futaba began with hopping and added direct sequence as FASST, and Spektrum began with direct-sequence DSM, added hopping in DSM2 and then DSMX; these are makers' system names, not confirmed performance claims. Wikipedia calls Spektrum's DSM the original application of 2.4 GHz spread spectrum to RC models, a claim for the maker. (Radio history)

Staggered start and grid

Start formats named in the rules. the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) uses a staggered start for electric qualifying and an F1-type two-row grid for all finals, with the top qualifier choosing the left or right side, while IFMAR's electric off-road rules (version of 13 November 2019) start main finals from a staggered grid of ten rows. (How a race meeting works)

Super Pole

A session named in IFMAR's IC track rules whose winner goes directly into the main final, alongside the top qualifier (IFMAR's 1/8 IC track World Championship rules (2023 edition); IFMAR's 1/10 IC track World Championship rules (2024 edition)). (How a race meeting works)

T

Tamiya's first RC car

Tamiya says its RC car line began in 1976 with the Porsche 934, a maker's claim it marked with a 50th-anniversary kit released on 23 May 2026. LiveRC says Tamiya released the 1/12 Porsche 934 Turbo in November 1976 as a kit without radio or servos (no other source for the month was read, so it rests on LiveRC alone); Motor Sport (July 2017) says it first ran on dry cells. (The first RC cars)

Technical inspection (scrutineering)

The check of cars and equipment by officials. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (3.27) allow one car per driver, marked at initial inspection, limit transmitters to the maker's recommended voltage with no external transmitter packs, and (3.8.e) always include the cars' safety aspects, with no sharp or protruding parts; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) sends each car to scrutineering after its heat, lets the organiser inspect any car, component or transmitter at any time, and lets an EFRA-appointed person dismantle the top three finishers' motors; IFMAR's electric off-road rules (version of 13 November 2019) add random lithium voltage checks. (How a race meeting works)

Ted Longshaw

A British organiser central to the histories read. IFMAR's own history calls him the driving force behind IFMAR and its first president from its inauguration in 1979 until he retired in 1995; Red RC's obituary (8 September 2011) says he proposed a world body with uniform rules after a World Championship in Switzerland in 1979 and took part in the first organised UK race in 1971; Wikipedia says he formed the BRCA in 1971 and was its first president, and that he was EFRA president until 1983. (IFMAR history)

Thermal runaway

The self-heating chain reaction behind lithium battery fires, as regulators and safety bodies describe it. OSHA says heat from one failing cell damages its neighbours, which can lead to fire, explosion and the release of chemical by-products such as hydrogen fluoride, and names internal short circuits, mechanical damage, excessive heat or cold and improper charging as causes; the UL fact sheet hosted by New Jersey's Division of Fire Safety gives a cell temperature of more than 1,000 F, while NTSB recommendations hosted by the FAA are summarised as giving 1,100 F or higher (unconfirmed); PHMSA and the FAA (safety advisory notice 09-05, 2009) said defective, damaged or overcharged batteries can overheat and ignite. A burning or smoking lithium battery is a matter for the fire service, and anyone hurt needs medical care. (Battery fire risk)

Timing systems

Automatic lap counting by transponder. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) require two independent approved timing systems running at once, recording lap times to 1/100 second, with the time-keeper deciding if they differ; EFRA's General Rules (2024 edition; the 2026 General Rules were not read) (5.4) also require two completely independent lap-counting systems at EFRA-sanctioned events; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) sets automatic timing announcements in clear English, including a 10-second countdown and race order every two minutes. (Timing and transponders)

Top qualifier (TQ)

The fastest driver in qualifying. IFMAR's 1/8 IC track World Championship rules (2023 edition) and IFMAR's 1/10 IC track World Championship rules (2024 edition) put the top qualifier directly into the main final; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) lets the top qualifier pick the left or right side of the grid for all finals; ROAR's National Guidelines (revised 13 October 2026) send the TQ straight to the final in fuel classes. (How a race meeting works)

Transmitter

The radio a driver uses to control the car. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) limit transmitters to the maker's recommended voltage with no external battery packs, and allow radios on only for the running heat and the next group; IFMAR's electric off-road rules (version of 13 November 2019) require every transmitter to be inspected and approved before use; ROAR's rule book revisions post of 18 October 2024 (the current rule book itself was not read) records that ROAR deleted its ban on switching radios on in the pits but kept rule 8.14.3.9 against radio use that affects another driver's car. (Radios and receivers)

Transponder

A small unit on each car that identifies it to the lap-counting system. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) (3.9) require every competitor to use their own compatible personal transponder, fitted securely at the driver's responsibility, and accept no lap score from any source other than the official timing; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) makes a driver using a personal transponder entirely responsible for its working and applies all minimum weights with the transponder fitted; IFMAR's 1/8 IC track World Championship rules (2023 edition) count no car without one in qualifying and re-run no heat for a failed transponder; ROAR's National Guidelines (revised 13 October 2026) require Nationals entry forms to state that personal transponders are mandatory. (Timing and transponders)

Trial visit (BRCA)

The BRCA's published route into racing allows up to three trial visits at a BRCA-affiliated club before BRCA membership is required, and points newcomers to its Club Finder and a Race With Respect conduct initiative. (How people learn)

Truggy

An off-road class name used by some bodies. Wikipedia's BRCA article lists a truggy section; Red RC reported on 2 August 2009 that FEMCA had submitted draft truggy rules to the IFMAR AGM; and LiveRC's results listing carries a 2026 ROAR 1/8 Electric Truggy National headline (headline only, unconfirmed). (Off-road arrives)

Turns (T)

The number of winding turns on a brushless motor's stator, written as, for example, 13.5T or 17.5T. the EFRA Handbook 2026, Appendix 4 (batteries and motors) fixes the turns for each spec class and sets no turn limit for Modified, and EFRA's spec list (21.5T, 17.5T, 13.5T and 10.5T) differs from IFMAR's (13.5T, 17.5T, 21.5T and 25.5T) in IFMAR's electric batteries and motors rules (March 2023). RC Car Action (2016, trade press) says more turns generally mean lower rpm. (Motors)

Tyre additives

Substances put on tyres for grip or cleaning, which bodies limit. IFMAR's 1/8 IC off-road World Championship rules (2024 edition, amended March 2024) disqualify anyone applying an additive inside the event perimeter; the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) leaves on-road additives to organisers and EFRA on health, nuisance and track-damage grounds, allows only the additive agreed at the AGM at European Championships and nothing but water on 1/10 off-road tyres, and draws organisers' attention to the possible hazard of many competitors using additives in a confined space; IFMAR's electric off-road rules (version of 13 November 2019) also allow only water. A 2015 LiveRC report says ROAR banned home-made traction compounds that were not commercially available (unconfirmed as current). (Tyres and bodies)

U

UN 38.3

The lithium battery tests in the UN Manual of Tests and Criteria, Part III, subsection 38.3 (tests T1 to T8). the EFRA Handbook 2026, Appendix 4 (batteries and motors) (3.3(a)) requires each battery submitted for EFRA approval to be covered by UN 38.3 certification, IFMAR's electric batteries and motors rules (March 2023) require the same for IFMAR approval, IATA's 2026 guidance requires batteries carried by passengers to be of a type meeting UN 38.3, and ROAR's 2011 rules as LiveRC reprinted them required a certificate showing the cells passed UN transport tests. The tests are an approval and transport requirement, not a finding that a pack cannot fail. (Batteries)

V

Voltage check

A check of a lithium pack's charged voltage by officials. IFMAR's 1/8 e-buggy rules (April 2023) check each 4S pack (at most 16.80 V) before any run; IFMAR's electric off-road rules (version of 13 November 2019) allow random lithium voltage checks at technical inspection; IFMAR's 1/8 GT and GTE rules (2025 edition) penalise GTE battery over-voltage; and a 2015 LiveRC report says a driver arriving at ROAR Nationals technical inspection with an overcharged or overheated pack was disqualified (unconfirmed as current). (Battery rules at events)

W

World Championship (IFMAR)

IFMAR's world title events, held by class and organised by a bloc on IFMAR's behalf. Red RC reported IFMAR's 2026 calendar on 12 June 2025; on 30 October 2026 the 1:12 electric Worlds at Foshan, China, had been cancelled (IFMAR's release, as LiveRC reposted it, says the rescheduled Bangkok event covers ISTC only and gives no reason), the 1:10 ISTC Worlds had moved to Bangkok, Thailand, and was still to come, with open practice scheduled for 11 November and qualifying and finals for 12 to 14 November 2026, and the Large Scale (Lostallo), 1:10 IC touring car (Gubbio) and 1:8 IC off-road (Texas) Worlds had finished, each result resting on trade press because no IFMAR results page was read. For the Texas event, Red RC's calendar gave 26 September and its stage 1 report and EFRA's minutes 27 September as the start, EFRA's minutes give Austin and Red RC's event coverage names Hutto; no source says whether Austin and Hutto name the same venue. (IFMAR World Championships 2026)

Z

Zero-timing profile (Boost 0)

EFRA's term for the speed-controller mode required in spec-motor classes, better known as blinky: under the EFRA Handbook 2026, Appendix 3 (electric cars, June 2026 v4) (A 4.3.1) it must leave the motor's preset mechanical timing unchanged, disable boost, turbo and cheat-mode functions, and use 6-step commutation following the motor's hall sensors one to one. (Speed controllers)