Swing drift is accomplished by swinging the boom tip over the top of which components when it reaches its apex?

Swing drift is accomplished by swinging the boom tip over the top of which components when it reaches its apex?

• A. Ball
• B. Block
• C. Ball or Block
• D. Pulley

Answer: (C)

Swing drift happens because the rope line changes its path as the boom tip passes over a guide at the top of a moving pulley assembly. When the boom reaches its apex, the tip goes over the top of the ball or the block, causing the line to wrap over that top edge. That top-wrap changes the line’s direction and introduces a horizontal component of tension, which pulls the load sideways and creates drift. A pulley doesn’t produce the same top-wrap scenario, whereas passing over the ball or block at the apex sets up the geometry that drives the drift. That’s why swinging the boom tip over the top of the ball or the block is the condition that accomplishes swing drift.

Swing drift happens because the rope line changes its path as the boom tip passes over a guide at the top of a moving pulley assembly. When the boom reaches its apex, the tip goes over the top of the ball or the block, causing the line to wrap over that top edge. That top-wrap changes the line’s direction and introduces a horizontal component of tension, which pulls the load sideways and creates drift. A pulley doesn’t produce the same top-wrap scenario, whereas passing over the ball or block at the apex sets up the geometry that drives the drift. That’s why swinging the boom tip over the top of the ball or the block is the condition that accomplishes swing drift.