vastakkaisrotorirakenteita

Vastakkaisrotorirakenteita, often translated as tandem rotors, refers to a helicopter configuration featuring two main rotor systems positioned one above the other. Each rotor rotates in the opposite direction to the other. This arrangement is designed to counteract the inherent torque produced by a single main rotor, which would otherwise cause the helicopter's fuselage to spin in the opposite direction. By having rotors turning against each other, the torque effects are neutralized, eliminating the need for a tail rotor.

The primary advantage of the tandem rotor design is its ability to generate significant lift and carry heavy payloads. The two large rotors provide a substantial surface area for generating thrust. This configuration also allows for greater stability and control, especially in hover and at low speeds. However, tandem rotor helicopters tend to be more complex mechanically due to the presence of two rotor systems and their associated gearing and control mechanisms. They are also generally less fuel-efficient than single-rotor designs. Examples of helicopters utilizing this configuration include the CH-47 Chinook and the Kaman K-MAX.