Why are some helicopter tail rotors tilted?

Upside: tilting thrust at small angles has large trigonometric effects. Thrust in the yaw direction reduces with (1 – cos20) = 6\%, at a gain in the pitch direction of sin20 = 34\% of tail rotor thrust. The stabilator has a decided effect on effective lift with the tail rotor.

Why does improved tail rotor efficiency in forward flight causes the helicopter nose to yaw to the left if the main rotor turns counter clockwise?

As the tail rotor works in progressively less turbulent air, this improved efficiency produces more antitorque thrust, causing the nose of the aircraft to yaw left (with a main rotor turning counterclockwise) and forces the pilot to apply right pedal (decreasing the AOA in the tail rotor blades) in response.

Why does the tail rotor becomes aerodynamically more efficient when a helicopter transitions from a hover to forward flight?

When the helicopter transitions from hover to forward flight, the tail rotor becomes more aerodynamically efficient. Efficiency increases because the tail rotor works in progressively less turbulent air as speed increases. As tail rotor efficiency improves, more thrust is produced.

What force does tail rotor counteract?

A helicopter tail rotor serves two essential functions. It provides a counteracting force to the helicopter’s main rotor; without the sideways thrust produced by the tail rotor, the torque generated by the main rotor would spin the helicopter’s body in the opposite direction.

Why is the Blackhawk tail rotor on the right side?

A change in each blade’s pitch creates uneven lift, allowing the helicopter to tilt and fly in a particular direction. By adjusting the pitch of the tail rotor, the pilot can turn the helicopter left or right.

What happens when a helicopter loses its tail rotor?

If the tail rotor fails in flight, engine torque can no longer be countered by the tail rotor, and uncontrolled spinning of the aircraft is a possibility. Most manufacturers call for an immediate autorotation. Some call for a running landing, instead.

How does helicopter get its lifting force?

In most cases, the lift for an aircraft is created with its wings. For a helicopter, a lift is generated by the way the main rotor blades are formed so the air is pushed in a downward movement when the blades spin. As the air pressure changes, the helicopter lifts up.

Do helicopters have two rotors?

All helicopters have two rotors… The main rotor and a tail rotor.

How does a tail rotor work on a helicopter?

The tail rotor or Anti-Torque system creates thrust to push the tail boom in the opposite direction to which it wants to turn from the torque. When the thrust from the anti-torque system matches the torque being created by the main rotor the helicopter will remain pointing forward when it lifts off the ground.

Why do helicopters have different pedals when making hover turns?

A helicopter requires differing amounts of pedal when making a hover turn because crosswinds constantly affect the fuselage and the airflow through the tail rotor. Crosswinds both vary the amount of thrust the tail rotor produces and make the fuselage want to weathercock into the wind.

Why do helicopters have coaxial rotors?

Coaxial Rotor Helicopters usually are able to lift more while maintaining the same engine power, when compared to single rotor helicopters Again, this has to do with the lack of a tail rotor that takes some of the engine power to operate. Helicopters have tail rotors to counteract the torque from the main rotor.

How does autorotation work on a helicopter?

During autorotation, the helicopter is no longer subjected to torque from the main rotor. This means that stable flight is attainable, even without the tail rotor. The pilot then makes sure to safely glide to a suitable landing site.