Yaw Damper???

[indian airlines]

What's the yaw damper hold button for. When is it used? What does it do? What does it mean to "damp the yaw"???

-Tanuj.

[LRJet Guy]

A yaw damper is a device that applies pressure to the rudder equally in each direction during flight. Its purpose is to prevent unwanted yaw of the aircraft in flight. By applying the pressure on the rudder, when the aircraft yaws, the rudder swings in the direction needed to stop the yaw without pilot input. It is usually engaged just after takeoff, and disengaged just prior to landing. In many aircraft it is a no go item, or the aircraft is speed restricted if it is inop. In aircraft with nosewheel steering connected through the rudder pedals, ground control can be seriously hampered if left on during the landing rollout, especially during crosswinds. I've done it a couple of times, and it sucks.

In FS98, it doesn't seem to do squat. Just there for looks and added realism.

[JeffinDEN]

T,

Yaw is movement about the veritcal axis (rudder inputs create yaw). Some planes have a tendency to oscillate on the vertical axis after input. The yaw damper as I know it, is a rate switching gyro connected to the AFCS (Automatic Flight Control System) that will sense, and counter fluctuations on the yaw axis. Not to be confused with heading hold.

Yaw Stab aug. is one of the three stability augmentation systems available to help put the pilot to sleep, err.... I mean help control the flight of the aircraft. The other two are Pitch Stab Aug. and Roll Stab. Aug. "Stab Aug" is short for Stability Augmentation. Very sensitive little gyros.

Did that help?

[indian airlines]

Thanks guys. That really helped.

Jeff, a few 'big words' here and there, but I understood what you were trying to say. :D

[screaming_emu]

Thanks guys. That really helped.

Jeff, a few 'big words' here and there, but I understood what you were trying to say. :D

by the two responses you can tell who the pilot and the mechanic are. Yeah, as I understand it the yaw damper is much like autopilot for the rudder. When an airacraft turns it uses the ailerons to change the bank of the aircraft, which allows the horizontal component of lift to turn the aircraft. But on the outside wing in the turn, the aileron goes down creating lift. Whenever lift is created there is what is called induced drag, which will make the aircraft momentarily yaw to the opposite way which you are trying to turn. The rudder's role is to cancel out this "adverse yaw" so that the turns are coordinated and much smoother. So as I understand it yaw damper does this automatically, correct?

[JeffinDEN]

Not exactly. That is called "ARI". Aileron, Rudder, Interconnect. It will automatically kick the rudder in the direction of the turn, thus creating the coordinated non-slipping turn with only airleron input. No rudder needed. This is based on the amount of aileron displacement and air speed if I remember correctly.

[screaming_emu]

Cool, thanks for the explanation Jeff.