What are the common types of helicopter rotor systems?

The classification of helicopter rotor systems is essential for understanding how different designs affect performance and handling characteristics. The correct answer identifies the common types of rotor systems used in helicopters: single rotor, tandem rotor, and coaxial rotor systems.

Single rotor systems are the most conventional design and consist of one main rotor that provides lift, with a tail rotor to counteract the torque produced by the main rotor. This system is widespread due to its simplicity and effectiveness in various flight conditions.

Tandem rotor systems feature two main rotors mounted one in front of the other, both rotating in opposite directions. This configuration effectively balances torque, eliminating the need for a tail rotor and allowing for greater lift capacity. Tandem rotors are often used in heavy-lift helicopters, as they can support larger payloads while maintaining stability.

Coaxial rotor systems consist of two rotors stacked one above the other, rotating in opposite directions. This design efficiently cancels out rotor torque and can enhance lift performance and maneuverability. Coaxial systems are found in some advanced helicopter models that require agility and compact design.

Understanding these rotor configurations is crucial for grasping the aerodynamic principles at play in helicopter flight and their respective advantages and limitations in specific applications.