In a pitch trim runaway, the initial action is to:

• A. Trim Interrupt/AP Disengage Switch - PUSH AND HOLD.
• B. Increase trim to stop runaway
• C. Turn off cabin pressurization
• D. Engage autopilot

Answer: (A)

When a pitch trim runaway occurs, the immediate goal is to stop the trim motion and take manual control. The quickest and most reliable way is to push and hold the Trim Interrupt/AP Disengage switch. This cuts power to the pitch trim actuators and disengages the autopilot, halting the runaway so you can stabilize the aircraft.

Raising trim would simply continue the runaway, so it’s not the right move. Turning off cabin pressurization doesn’t affect the trim system, and engaging the autopilot during a trim runaway would likely try to hold or worsen the undesired pitch movement instead of curing it. After interrupting the trim and autopilot, you can manually stabilize the airplane and re-establish safe control.