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main rotor

main rotor

1 4.5
A large set of spinning blades on a helicopter that lifts it into the air
  • noun
  • /meɪn ˈroʊtər/
  • Specialized
translation icon : rotor principal
  • The pilot adjusted the main rotor's pitch to improve the helicopter's performance in the air.
  • main rotor blade

Examples

  • - We'll tear off the main rotor.

  • How's the main rotor RPM?

  • More birds pepper-shot the helo: one shreds through the main rotor.

    Fiction book (1997)
  • To eliminate torquing, Sikorsky mounted a small rotor on the end of the fuselage to act as a fan that blew counter to the rotating force of the main rotor.

    Academic text (2003)
  • Once the control problems were better understood, Sikorsky and his team were able to eliminate first one and then both of the horizontal auxiliary rotors, opting instead to change the pitch of the main rotor to control longitudinal and lateral motion.

    Academic text (2003)
  • The main rotor of the helicopter provides the necessary lift for flight.

  • During maintenance, the technician inspected the main rotor for any signs of wear.

Synonyms

rotor
vsmain rotor
  • Specialized
23 5.4

A set of blades that turns to move air or make electricity, like on a helicopter

is the helicopter specific large assembly rather than any rotating part
rotary wing
vsmain rotor
  • Specialized
1 6.9

A set of long rotating blades on a helicopter that lift it and let it hover

is larger and names the full blade assembly rather than just the airfoil

Surface Forms

main rotor singular
main rotors plural

Morphology

main + rotor

The meaning is directly compositional: 'main' (= primary) modifies 'rotor' (= rotating assembly with blades), so a B1 learner who knows both words can infer this refers to the helicopter's primary rotating blade assembly. This follows standard noun + modifier composition and is cross-linguistically transparent for learners, despite being a technical term.

Etymology

Main rotor combines main (the biggest) and rotor (something that 'turns'). Imagine the big spinning set of blades on top of a helicopter that turn like a giant fan and give the aircraft 'lift', so main rotor means the large set of blades that spin and support flight.