Which component reduces nose wheel shimmy at certain speeds?

• A. Strut damper
• B. Shimmy damper
• C. Wheel damper
• D. Tire damper

Answer: (B)

Nose wheel shimmy is a lateral oscillation of the nose wheel that can occur at certain speeds due to the interaction of wheel inertia, tire forces, and steering geometry. The way this oscillation is controlled is with a shimmy damper, a specialized hydraulic damper placed in the nose gear steering path. It resists rapid angular motion of the wheel about the steering axis and dissipates the energy of the oscillation as heat. This damping increases the stability of the nose gear when conditions would otherwise let the oscillation grow, preventing uncomfortable or damaging shimmy during taxi, takeoff, and landing. The strut damper handles vertical motion of the leg itself, not lateral wheel oscillations, and terms like wheel damper or tire damper aren’t used to address shimmy in the same targeted way.