Tree Work
Swing Radius Calculator
When a piece swings under a rigging point, it travels in a pendulum arc. The swing radius determines what it will hit. Enter the rope length and attachment height to get the swing footprint.
Max swing radius (ft)
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- Bottom of arc height (ft)
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- Top of arc rise (ft)
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- Approx peak swing speed (ft/s)
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FAQ
Why does swing radius matter? +
Anything inside the swing arc can be hit by the piece. Drop zone planning has to include the full radius — not just the spot directly below the rigging point.
What is "bottom of arc height"? +
The lowest point the swinging piece will reach. If this is below ground level, the piece will hit ground before it stops swinging.
How fast does it move? +
A 30° swing on a 40-ft rope drops the load about 5.4 ft as it crosses the bottom of the arc, hitting peak speed around 19 ft/s (13 mph). That impact energy is the whole reason for the swing.