What is the correct action to initiate a quick stop in a helicopter?

In a helicopter, initiating a quick stop involves effectively managing the lift and forward momentum to achieve a rapid deceleration and halt. The correct action entails lowering the collective pitch to reduce lift and applying aft cyclic to pitch the helicopter nose upwards, which consequently reduces forward speed. By lowering the collective pitch, the amount of lift generated is decreased, while the aft cyclic changes the angle of attack and directs the lift vector more vertically, helping to counteract forward motion.

This combination allows the helicopter to decelerate quickly while maintaining control, leading to an effective stop. Understanding the dynamics of lift and how the cyclic controls the helicopter's pitch is crucial for executing a quick stop safely and effectively.