What Are Yaw Dampers and Why Are They Important?

From fully mechanical systems to using a computer with a high-speed processor to control the aircraft, autopilot systems have come a long way since the early days of flight. One such advancement has been the addition of a yaw damper, that of which is an autopilot feature that controls the rudder and applies corrections any time the system detects slips or side-to-side forces. Having first become necessary with swept-wing aircraft that needed help with stability, yaw dampers have quickly become a regular component on aircraft of all types, where it can provide a much smoother ride for passengers and crew alike.

What Is Yaw?

As one of the three axes of movement that an aircraft can move along, yaw refers to the direction that the plane is pointing from right to left. It is most important to control yaw when making a turn in the air, and planes are typically able to achieve this range of motion by using their rudder and ailerons. Much like the rudder on a ship, aircraft rudders consist of a moveable fin on the tail of the plane that can be adjusted to the right or left to change which direction the nose is pointing. Conversely, the ailerons are control flaps on the wings which can be angled up or down to help the plane “roll” to one side or the other. When combined with the motion of the rudder, a plane can raise one aileron and lower the other to make a turn to the pilot’s left or right, thereby changing its yaw.

What Is a Yaw Damper?

While a plane’s yaw can be controlled using its rudder, the pilot must also account for other forces which will affect the plane’s yaw. Often, air currents or parts of the aircraft itself can force the plane to one side. When this happens, the autopilot’s yaw damper feature will kick in, working like an extra set of feet tilting the rudder to keep the plane heading along its proper course. Consisting of two major parts, the yaw damper can detect adverse yaw using a gyroscope, adjusting the rudder as necessary via the valves and actuators which add hydraulic power to the movements made by the pilot. Nevertheless, the system is also equipped with several indicators which ensure that the pilot is aware of each adjustment that the yaw damper makes, and they always have the option of switching the device off if full manual control is needed.

Why Do Some Aircraft Need Yaw Dampers?

While many aircraft employ a yaw damper mainly as an optional way to relieve the pilot’s workload and create a smoother flight, the yaw damper is oftentime a crucial feature of the plane’s safety system. In this case, the yaw damper is important for preventing the onset of a severe dutch roll. When a dutch roll occurs, it starts with one wing getting pushed down, possibly due to turbulence or a control input. The resulting sideslip stabilizes the wing and brings it level, which happens faster than the nose coming back into the relative wind. Since these two corrections happen at a different rate, the nose of the plane is swung in a figure-eight in the sky. Most airplanes are able to come out of dutch roll quickly, but high-altitude swept-wing aircraft are very susceptible. As such, these planes are always equipped with one or more yaw dampers, ensuring pilots do not lose control of their aircraft.

Conclusion

Yaw dampers were a pivotal invention when they were first introduced. In addition to solving the major issue of dutch roll for swept-wing aircraft, this autopilot feature makes flying easier for pilots and more comfortable for passengers. Here on Single Source Aero, we offer an array of quality-sourced yaw damper parts, alongside other aircraft components. We are proudly an AS9120B, ISO 9001:2015, and FAA AC 00-56B accredited enterprise, meaning that we go to great lengths to uphold a high standard of service and quality for our customers. If you are currently on the search for reliable parts, we invite you to browse our online catalog and make use of our RFQ service to receive competitive quotes for your comparisons. Our team of experts are available 24/7x365 to answer customer inquiries and requests, meaning all RFQ forms will be returned in just 15 minutes or less!