Tandem rotors
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Tandem rotor helicopters have two large horizontal rotor assemblies instead of one main assembly and a smaller tail rotor.
Single rotor helicopters need a tail rotor to counter the twisting moment produced by the single large rotor. Tandem rotor helicopters, however, use contra-rotating rotors, with each canceling out the other's torque.
This configuration also has the advantage of being able to hold more weight with shorter blades, since there are two sets. Also, all of the power from the engines can be used for lift, whereas a single rotor helicoptor only uses one main rotor for lift with the tail rotor only to counter the torque.
[edit] See also
[edit] List of tandem rotor helicopters
- PV 3 Dog Ship, HRP-1 (1945)
- Piasecki PV 14 (1948)
- Piasecki H-21 (1949)
- Piasecki PV 17 (1950)
- Piasecki PV 18 Retriever "HUP" (1952)
- Yakovlev Yak-24 (first flew 1952)
- Bristol Belvedere (1952)
- Piasecki PD 22 (H-21) (1953)
- Piasecki PV-15, YH-16 (1953)
- Bell Model 61 / HSL
- Boeing-Vertol 107-II (1958)
- CH-46 Sea Knight (1960)
- CH-47 Chinook (1961)
- Boeing-Vertol 347 (1970)
- Boeing-Vertol Model 234 (1980)
- Boeing-Vertol Model 360 (1987)
[edit] Transversal scheme
- Bratukhin G-3 (1946)
- Bratukhin B-11 (1948)
- Kamov Ka-22 (1959)
- Mil Mi-12 (1967)
