The Collective Trim beeper can be used below 50 KIAS, about the yaw axis to adjust ___

• A. heading left or right
• B. pitch
• C. roll
• D. altitude

Answer: (A)

The thing being tested is how trimming works to control heading at low airspeed. The collective trim beeper is used to apply a small yaw correction, which changes the tail rotor thrust just enough to nudge the helicopter’s nose left or right. Doing this below about 50 KIAS takes advantage of the limited aerodynamic damping and makes heading adjustments with minimal pedal effort. This kind of trim specifically affects heading, not pitch, roll, or altitude. Pitch and roll are controlled mainly by the cyclic, while altitude is managed by the collective overall thrust, so the trim on the collective around the yaw axis is the tool for fine-tuning heading.