Core Technical Terms
Autorotation – Landing maneuver using rotor inertia when the motor is off.
BEC (Battery Eliminator Circuit) – Voltage regulator that powers the receiver from the main battery.
Center of Gravity (COG) – Balance point of the helicopter, critical for stable flight.
ATV (Adjustable Travel Volume) – Radio setting that adjusts servo travel limits.
Dual Conversion Receiver – A receiver design that reduces interference.
Buddy Box – Training system connecting two transmitters so an instructor can take control.
Channel – Refers to either the radio frequency or a control function (e.g., throttle, rudder).
Crystal – Component that sets the operating frequency of the transmitter/receiver. (no longer used in modern radios)
Helicopter-Specific Terms
Boom Strike – When rotor blades hit the tail boom.
Blade Strike – Any rotor blade hitting an object, often the ground.
Belt Slap – Tail belt hitting the inside of the boom, making a popping sound.
Flying on Rails – Describes precise, stable flight.
Blade Fart – Sound made by inefficient blades under aggressive flying.
Chop Hop / Bunny Hop – Quick pitch reversals causing the heli to hop.
Auto Plow – Crash caused by mechanical failure.
Slang & Field Expressions
“4th of July” – When LiPo batteries eject mid-air and explode dramatically.
Blade Scrape – Rotor tips momentarily touch the ground but recover.
Box – Designated flying area when multiple pilots share a flight line.
Blade Sniper – Grinding blades on tarmac until weights eject dangerously.
Braaapppp – Slang for the sound of two-stroke engines.
