Definition
A condition in a helicopter rotor system in which the rotor blades are producing little or no lift, so the aircraft's weight is no longer being supported by the rotor. This typically occurs during low-G or pushover maneuvers when the pilot abruptly lowers the nose, momentarily reducing the load the rotor carries.
Plain English
The rotor is spinning, but for a moment it isn't really lifting the helicopter — the weight has come off the blades.
Context Anchor
Seen in helicopter aerodynamics, low-G maneuver discussions, and safety training for rotor systems that can be damaged by sudden unloading.
Derivation
“Unloaded” comes from “load,” meaning weight or burden. In this term, the “load” is not cargo; it is the force the rotor normally carries while holding the helicopter up.
Why Pilots Care
In two-bladed rotor systems an unloaded rotor can allow excessive teetering and mast bumping, which may damage the rotor head or cause loss of control.
Grounding Statement
Picture a quick nose-down push that makes everything in the helicopter feel light for a moment; the rotor has been unloaded.
Intuition Check
Unloaded does not mean the helicopter has no passengers or cargo. Here it means the rotor is not carrying its normal lifting load.
Example Sentence 1
The instructor warned that a sharp forward push on the cyclic could produce an unloaded rotor and risk mast bumping.
Example Sentence 2
During the quick stop maneuver the rotor unloaded momentarily before the pilot added collective.