How can V-22 Osprey fly (take off) without an anti-torque device? Every helicopter must have it!?

Question

It's such a mystery. I looked at pictures, but they don't have antitorque!

Answer 1

The blades spin in oposite directions. The torque on one counteracts the torque on the other. Voiala, no antitorque device necessary. Not unlike a CH47 Chinook.

Answer 2

The correct answer is the V-22 aircraft does not need anti torques devices. Please continue to read and I will explain it more and why.

This aircraft has two Rolls-Royce AE-1107C free turbine turboshaft engines, modular design, 14 stage axial compressor, annular combustor, 2 stage gas generator turbine, 2 stage power turbine, bottom mounted power section accessory gearbox, two single channel full authority digital electronic controls.

The engines are Type Certificate Data Sheet and the TCDS is NO. E00008CH by Rolls-Royce Indianapolis, Indiana. When the engines are installed they are considered public use, as is the aircraft. The AE 1107C model is intended for a US military application. Current US law does not require that public use or military aircraft/engines be operated or maintained in accordance with the FAA approved type design.

The AE 1107C model is intended for use only in a dual engine application 6,150 shp (4,586 kW) each.

Both engines rotate the same direction on the Bell V-22 cross-coupled transmissions allow either engine, separately or together, to power the rotors. The rotors turn different directions canceling out the adverse torque effect. This is why you do not need anti torque pedals or other devices.

On the instrument panel there is a torque meter that registers engine torque for each engine. A black box is install, which allows the engines to talk back and forth thru an electronic coax cable when engine torque changes and adds more fuel to balance the torque or RMP as required.

As a side note Rolls-Royce Oakland Engine Repair Station overhauls all the AE1107 engines when required.

Reference:
http://www.bellhelicopter.com/en/aircraft/military/bellV-22.cfm
http://www.boeing.com/rotorcraft/military/v22/docs/V-22_overview.pdf
http://www.faa.gov

Answer 3

Have a look at the picture in the link below. You can clearly see the rotors on each side configured for contra-rotation. In this case the torque of each rotor cancels out the other's. Other examples are the Chinook, the Kamov helicopters and the Kaman Huskie.

Answer 4

It seems you missed a few things in the aerodynamics class. Choppers can use either an anti-torque device such as a tail rotor or Boeing's NOTAR, or it can use another rotor.

V22's rotors rotate opposite of each other. Thus, their torque cancel each other out. That puts in in the second camp.

A similar though more conventional chopper is the Kamov KA-50 or Ka-52 "Werewolf" / "Alligator"

http://en.wikipedia.org/wiki/Kamov_Ka-50

Two rotors, one on top of the other, going in opposite directions. Again, no "net" torque.

Choppers with tandem rotors such as

http://en.wikipedia.org/wiki/CH-46_Sea_Knight

are also in this camp as well.

Answer 5

The same principal the CH-47 Chinook uses, counter-rotating, sychronized rotors.

As for "every helicopter must have it" you are correct. But, it's not always in the form of a tail rotor. There is also the conter-rotating main rotor, like on the Kamov aircraft, and the NOTAR (No Tail Rotor) aircraft which uses a pressurized tail boom with controllable slits at the end.

Answer 6

Dual rotor craft need nothing to cancel the torque. The rotors cancel each other. Look also at the CH-47 Chinook and the Kaman K-225 and K-1200 K-MAX with intermeshing rotors.

Answer 7

Because the engines are not in line with the fuselage; in straight flight it is a regular airaft with engines on the wings the wings rotate so the torque is not linear down the fuselage which is the cause for the problems with helicopters, even the old flying banana's and the CH-46/47's still in service.

Answer 8

They have engines that counter rotate. The props cancel the torque from each other.

Look at helicopters like the ch-46 and ch-47, no anti-torque devices either,

Answer 9

counter rotating props

oh, as for your answer firefox, contra rotating props are mounted on the same axis... just wanted to clear that up and get the terminology right
http://en.wikipedia.org/wiki/Contra-rotating_propellers

Answer 10

Isn't the Osprey the one with the twin JET engines? No propellors, no torque question.