RC dictionary

It can be quite difficult to get into RC without knowing the words. Remember, i`m not an expert, so let me know if I got anything mixed up. This post is under construction! Any one post with XXXXX in front of the word, is under -heavy- construction.

A:

Ailerons: The controlsurfaces on the wings. By using these surfaces, a airplane can go into a roll. See an animation here. or a picture here.

ARF/ARR: AlmostReady(to)Fly, AlmostReady(to)Fly. You have to attach some parts before it is RTR.

AST: One adjustment of ATV aftects both ends of servo throw. Also see ATV and EPA.

ATV: Adjustable Travel Volume. A setting to limit, decrease or increse the amount of travel at both ends of the travel of a servo. The ATV can be adjusted by altering the EPA or the AST. Also see EPA and AST.

Autorotation: A function in the more expensive helicopter models. If the engines fail, instead of the rotors stopping instantly, they go into neutral. Even though the engine stops, the rotors have enough speed to give lift for (hopefully) a little while, in which the heli can landed. See it done on a non-RC heli here.

Ampere: Shortned to a capital A, the unit of electrical current.

B:

Bank/Roll: A movement caused by using the by the ailerons. See a animation here.

Biplane: Airplane term. A airplane with two wings. Also see sesquiplane.

Blueglue: Glue used on EPP models. If you buy a AirAce plane, you get one of these. It is probably a polyurethane based glue, but not sure.

BEC: Battery elimninator circuitry. If a ESC has BEC, it can deliver power to a receiver, and hence the receiver don`t need a separate battery. It also ensures that you can enough power to the servos, so it might cut the motors earlier, leaving the controlling servos working for a safe landing. A BEC is best for a low cell count, as they cut off prematurly with a high cell count. Limits the amount of servos that can be used, around 3-4 servos. Also see SBEC and UBEC.

Bell link: The link between the servo horn and the swashplate. It is very often adjusable in lenght by turning it like a screw.

Boom strike: Heli term. When the rotor hits the boom during flight or at landing. THe boom is the “stick” between the main part of the heli and the tail rotor. Will result in splintering the rotor if it is made of wood. Can happen if you land to hard or doing a very hard manouver on a coaxial heli.

Break: A function in the ESC. Can be set by a ESC programmer card. If the break is off: If you pull the transmitter throttle fast to 0%, the motor will go into neutral and spin freely untill it stops. If the break is on, the motor will reverse and stop the engine quickly.

Brushless motor, BLM and brushed motor. BM: I won`t go into the details of why, google it if you`d like, but in generall brushless motors are better than brushed motor. They are easy to distinguish from the brushed, since brushless has 3 wires coming out of the motor, while brushed has only two. There are ESC`s for brushed motors and for brushless.

C:

Catamaran: Boat term. An intermediates hull. Less surface area to water then the Deep V hull and therefore greater speeds and less controll if unexperienced. Also see Deep V and Hydroplanes.

CCPM: Cyclic Collective Pitch Mixing. Heli term. The transmitter takes one input, and translates that into something two or three servos can understand. In effect, by pushing one of the sticks on your transmitter, CCPM makes sure that the servo push just right to create the desired movement. It ables you to change the pitch of the blade according to your input in Idle Mode or to your set throttle curve in Normal mode.

CG: Center of gravity. It defines how the plane wil act in the air. If it is noseheavy, it will tend to drop the nose when you cut the throttle and be very stable in flight but not reactive to your input yet be stable. A tailheavy airplane will tend to stall and be unstable, but will have really quick turns and in flight. A balanced airplane is best, slightly noseheavy though.

Control surface: The surface that steers on a aircraft, like the rudder, the ailerons or the elevators. See a nice illustration of what they all do here.

Coupling: See Mixing.

CyanoAcrylate/CA: Superglue. Will attack styrofoam and EEP!

Channels, CH: A transmitter have a set number of channels. It tells you how many thing it can controll at once. A 4CH transmitter can controll 4 things, lets say two motors and two servos.

Crystal: You put one crystal in the transmitter and one in the receiver. The frequency is determined by choice of crystal.

Coaxial helicopter: A helicopter with two rotors and no tail rotor. Usually very stable and easy to fly. Does not work well with ANY wind. Esky Lama V3/v4.

Coulomb rating: It tells you how fast you can draw power from the battery. Let`s say you have a 1000 mAh battery with a C-rating of 20C. This means that you can draw 20 times the capacity at any given moment, in this case you can draw 20 A continously. Some batteries have burst rating too, this is how much you can draw maximum for just a very short moment.

Cut-off type: A function in the ESC. Can be set by a ESC programmer card. When the battery is almost empty, the ESC detects that the battery is on the cutoff voltage. If the setting is “hard” the motor will stop immedialty when reaching the cutoffvoltage. “slow” will power down more and more, and give you a chance to land.

Cutoff-voltage: For NiXX it is 0,9volts per cell and for LiXX it is 3 volt.

D:

Dihedral wing: Also known as V-wing. See Deltawing

Digital servo: See Servo, Digital.

Deans-connector/T-connector: A connector used in the the higher pricerange of esky helicopters. Built for high currents.

Deep V: Boat term. Describes the shape of a RC boat with a V-shaped hull. This is a beginners hull, which slices through waves and has a large contact area to the water. This makes the boat go slower, but gives better manouverebility in rough water. Same as Mono hull or Deep Vee. Also see Catamaran and Hydroplane.

Deltawings: Airplane term. An airplane with a deltashaped wing (Triangle). Also called a V-wing or dihedralwings. Needs V-wing mixing of the aileron channel and the elevator channel into an elevon.

Dual Conversion: Transmitter term. A transmitter which has dual conversion filters the incoming signal through two separate electronic filters and washes out unwanted signals. It helps wash out signals coming from transmitters that are broadcasting at similar frequency, but it does not help if it is broadcasting the the same frequency.

Dual rates: Transmitter term. Radio functions to adjust control sensitivity

E:

Elevators: The controll surface on the horizontal trailing edge of the tail. It controls the pitch on a aircraft

Elevon: A combination of ailerons and elevators in two controlsurfaces used on deltawings/V-Wings. You probably need to use a V-wing mixer to get this right on a deltawing if you use a stock transmitter. See a picture here.

EPA: End Point Adjustment.One adjust each on the ATV for each end of the servo. See also ATV and AST.

EPP: Expanded Polypropylene. A very though material. AirAce make planes in this material. You can crash alot, and there is nothing that blueglue/polyurathane glue and some tape won`t fix.

Epoxy: A glue good for gluing wood and EEP. Be sure to test it on a small part first on the EEP just in case.

ESC: Electronic Speed control. This controles the motor. One kind for brushed motors and one kind for brushless. You connect this one to a motor and to a receiver. Is either BEC/SBEC or OPTO. You can change the settings of a ESC with a ESC programmer card.

ESC programmer card: A way to reprogram ESC`s. YOu can change throttle curve, breaking, cutoff type, motor type.

F:

FM: Frequency Modulation. See PPM.

Flybar: Heliterm. The flybar/stabilizer is a weighted/paddled stick connected to the rotor. This spins along with the rotor, keeping both blades level relative to each other.

G:

Gyro, gain setting: Sets the gyros sensitivity. If it is set too low, the tail will not hold it`s position. If set to high, the tail will wag slightly.

Ground effect/Ground wash: While the aircraft is close to the ground, a cushion of air gives the aircraft more lift.

Gyro type, normal (rate) and headlock: Heli term. A gyro senses when external forces on the heli, and counteracts them by telling the motors and servos what to do. Then the pilot can consentrate of flying instead of constantly having to correct for wind. A rate gyro only counteracts the torque from the main rotor, allowing the wind to shift the tail to some extent. It will “weathervane.” Headlock gyro is alot more accurate and forces the tail to stay in position regardless of any wind. With a headlock gyro it is abit more difficult to fly straight forward , but easier to fly 3D manouvers. It will not “weathervane”. See also weathervane if necessary. See a guide about installing one here.

H:

Headlock Gyro: See Gyro.

XXXXXHeadspeed: See how to calulate your headspeed without a tachometer here or here.

Hov.Pit-Hover Pitch: Heliterm. Changes the pitch on any given throttle setting. “Moves” the throttle curve, does NOT change it. Set a more Positive setting: At zero throttle it will have a more positive pitch. A more Negative setting: At zero throttle it will have a more negative pitch.

Hydroplane: The hull for the experienced. As the name suggests, this hull almost flies over the water. Little contact with water, high speed and little controll for the unexperienced. Also see Deep V and Catamaran.

I:

Idle mode: A mode you can choose from a 6CH transmitter on CCPM helicopters. In idle mode, the throttle stick on your transmitter changes from controlling the motor RPM (With a preset throttle curve), into using the throttle stick for controlling the rotor pitch directly at full RPM from full negative pitch (0% on throttle), via zero pitch (50% on throttle) to full positive pitch (100% on throttle). NOT for beginners! Enables inverted flight. Also see Normal mode.

Inrunner: A motor where the rotation takes place inside the motor core. Less torque and more rpm then the outrunner. Often used in conjuction with a gearbox to decrease rpm and increase torque. Spins to fast for aircraft (4000KV+)

Inverted flight: Flying upside down. Particulary hard on a helicopter. You need a CCPM helicopter in Idle mode to do that. And a lot of practise.

J:

XXXXXXXX: Jesusbolt: Heliterm. A bolt keeping the rotorhead attached to the rest of the helicopter. If you break this one, your heli is thrashed.

JST-connector: A connector used in the cheaper lines of Esky helicopters. Not designed for the amount of current the Dean connector is.

K:

Kit set: A kit contains only parts of what you need to make it RTR/RTF, or they contain every part and needs to be put together.

KV-rating: A rating for how fast motors spins. given in RPM per volt applied onto the motor. 10v on a 2000KV motor would give 20000rpm.

L:

Leading egde: The edge on a airplane closest to the nose. See also trailing edge. See a picture here.

LiPo: A battery based on lithium, with a polymer membrane between + and -. About 3x more mAh on the same weight in NiMH/NiCd batteries. VERY IMPORTANT. Lipos are very dangerous to handle in the wrong way. If you are new to lipo batteries, read this guide

Li-Ion:A battery based on lithium. About 3x more mAh on the same weight in NiMH/NiCd batteries. Also see LiPo.

M:

mAh: Milli-Ampere-Hours. Tells you the capacity of the battery along. Let`s say a battery has 2000 mAh, on a device that demand 1 ampere per hour. Then the battery wil last you about two hours.

Mixing: A electronic device that`s takes one input from the transmitter and translates that into servo movements on many servos. CCPM uses mixing to acheive the right movements on at least 3 servos using 1 input from the transmitter. V-wing mixing translates one channel into 2 servos inverse and one channel in moving the same servos identical the way.

Mode 1/2: The placement of the different functions on the transmitter. Mode 1 has throttle/aileron on right side, while mode 2 has rudder/throttle on left. Mode 1 is common in Europe/Asia, while Mode 2 is common in USA.

Mono hull: Boat term. See Deep V

Motor type: A function in the ESC. Can be set by a ESC programmer card.Normal motor (2,4,6 pole) and outrunner.

Motor shaft: The little pole sticking out of the motor which rotates! 😉

XXXXXXXXXXMotor size, electric: 180, 460.. Bigger number is bigger motor.

N:

Normal mode: A mode you can choose from a 6CH transmitter on CCPM helicopters. In Normal mode, the throttle stick on your transmitter controlles the motor RPM directly. You can on more expensive helicopters change the throttle curve (pit.trim knob) and hover pitch (Hov.pit) on the transmitter. Also see Idle mode.

O:

Outrunner: A motor with a rotating outer shell. Much slower then a Inrunner, but alot more torque. Great for aircrafts, as it has a low weight and lots of torque.

Opto: Meaning that an ESC does not have a BEC.

P:

PCB: Printed Circuit Board. See a general example here.

Pitch: A movement caused by using the elevators on a airplane. See an animation of it here.

XXXXXPit.trim-Throttle Curve Pitch Changes the throttle curve.

XXXXPoles in motors:

Propeller numbers: Airplane term. Props are sized up by two numbers, like “12 X 8”. 12 is the diameter or the prop in inches (1 inch=2,54cm). 8 is the distance the prop will move forward in one revolution, also in inches.

Pushrod: The rod between a servo output arm and a controlsurface.

Polyurethane: A kind of glue good for gluing EEP.

PCM: Pulse Code Modulation. Better then PPM, got cleaner signal.

PPM: Pulse Position Modulating. Also called FM.

Q:

R:

Receiver, RX: The receiver receives the signal from the transmitter. The receiver has so and so many channels, often from 4CH to 6CH, just like the transmitter. It gets it`s power from a ESC with BEC, from a ESC with SBEC or from a separate battery. The first is most common.

Retracts: Aircraft with retracts has retractable landing gear.

RFI: RC term. Radio Frequency Interference

Rudder: Control surface on the vertical stabilizer/fin on a airplane. When moved it makes the plane yaw. See an animation of it here.

Roll: A movement caused by using the ailerons on a airplane. See an animation of it here.

RTR/RTF: ReadyToRun, ReadyToFly. You can use this item straight out of the box. No need to bring your screwdriver.

RPM: Rotations per minute.

S:

XXXXXXSBEC: See also BEC and UBEC.

Servo, Analogue: A little motor which push, it does not spin. Often it can only push a centimeter or two. On a helicopter, servos are used to push the swashplate and therefor steering. You move the servos directly through the transmitter. Also see digital servo and servo output arm.

Servo, Digital:

Servo output arm: The plastic part on the servo where you connect the pushrod.

Sesquiplane: Airplane term. A biplane with one wing shorter than the other. Also see biplane.

Slop: When the movement of a servo doesn`t move the control surface immediately. Caused by worn linkages or to big holes in control surface connection.

Stabilizer: For the heliterm see flybar.

Swashplate: The plate underneath the rotors on a helicopter. When the servos push the swashplate, the rotors shift direction through connecting rods. This makes the rotors blow wind in a diffrent direction, making the helicopter go the other direction.It is crucial that it is level, see also swashplate leveler.

Swashplate leveler tool: A tool to get the swashplate totaly level. Make one yourself, see here.

T:

Tachometer: An optical device that counts light pulses through a moving propeller/rotor and reads out the RPM. Also see headspeed.

Throttle curve: A function in the ESC. Can be set by a ESC programmer card. Can be linear, expnential or logarithmic. A linear mean that at 50% on your transmitter, the motors are at 50%. Logaritmic increases this, yes, logarithmically. So at 20% on the TX, you got 30% on the motor, while at 50% on the TX you got 80% on the motor. Exponential means that you get most power increase at the start and the end, inverse of the logarithmic. On this picture you see 3 curves, the red one being the logarithmic one and the blue one being the exponential one.

T-connector/Deans:A connector used in the the higher pricerange of esky helicopters. Built for high currents.

Trailing edge: The edge on a airplane`s wing closest to the tail. Where the air rejoins after being separated by the leading edge. See also leading edge. See a picture of a leading edge here.

Transmitter, TX: The controller you steer with. The transmitter, or controller, can have from 2 channels, on to 4, 6 and many more. Budget rc covers up to 6 channels.

Trimming: You can trim a little bit while you are flying on the transmtiter. If that doesen`t help, you have to trim via lenghening/shortening the link between the servo and the control surfaces.

Torque: Moment of force. How much the motor can push. A tractor for example has alot of torque.

U:

UBEC: Abbreviation for Ultimate Battery Elimination Circuit. See also SBEC and BEC.

V:

V-Wing: See Deltawing.

W:

X:

Y:

Yaw: A movement caused by using the by the rudder. See a animation here.

Y-link/Y-harness: A wire from that makes one transmitter channel steer two servos the same. Used when the power of one servo is not enough.

Z:

4:

4-in-one: Used in helicopters, it`s a ESC, receiver, gyro and motor/servo mixer in one. Remeber: If you change any settings on the 4-in-one, you must do it while the battery is OUT, then wait about 5 seconds before you reconnects the power. Or else the new settings won`t take effect.