The aircraft yaws uncontrollably to one side even when rudder pedal input is applied in the opposite direction.

• A. Elevator System Jammed
• B. Rudder System Jammed
• C. Stabilizer Trim Runaway
• D. Unreliable Airspeed

Answer: (B)

Yaw is controlled by the rudder, so when the aircraft yaws uncontrollably to one side even as you push the opposite rudder, it points to a failure in the rudder system itself. If the rudder is jammed or physically stuck, the pedal input cannot move the rudder to oppose the yaw moment, so the airplane continues to yaw in that direction regardless of what you try. The other issues listed would affect pitch (elevator jammed or stabilizer trim runaway) or instrumentation (unreliable airspeed) rather than preventing rudder movement or causing a persistent uncountered yaw. So a jammed rudder best explains the situation.