Loss of Radio and Load Drift During a Critical Lift
You are the lift supervisor for a 120 t pick of a prefabricated module onto a 40 m high structure. The crane is a 400 t crawler, load at 28 m radius, wind 9 m/s steady. Mid-lift, the load is 35 m up and clear of the structure when the rigger's radio fails and the operator loses voice contact. The load begins a slow pendulum, and the operator cannot see the landing point or the rigger. The tag line handler is holding tension but is being pulled off balance. A second crane is working 15 m away.
1. What are your immediate priorities and actions?
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Priority one is to stop the load moving further and protect people. Signal the tag line handler to release the line and move clear - a person being pulled off balance by a drifting 120 t load is at risk of being dragged or crushed. Clear the area beneath and around the load. Establish communication with the operator by whatever redundant means is available: a backup radio on a pre-agreed channel, hand signals from a position the operator can see, or a runner to the cab. The lift plan should have nominated these backups before the lift; if it did not, that is a planning failure to record.
Instruct the operator to hold the load stationary and let the pendulum damp naturally - do not chase it with slewing or booming, which can amplify the swing. Confirm the second crane's status and keep it clear of the exclusion zone. Do not attempt to land the load blind. Once communication is restored, assess whether the load and rigging are intact, then either complete the landing under controlled conditions or lower the load to a safe set-down area.
2. What should have been in the lift plan to prevent this situation, and what is your post-incident response?
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The plan should have nominated primary and backup communication, a designated signal person, agreed hand signals, and a rule that the lift pauses if communication is lost. It should have set a wind limit and a method of measuring wind at load height, defined the exclusion zone around both cranes, and required tag line handlers to be positioned so they can release safely and are never in the fall zone. A critical lift of this type should have had a pre-lift meeting and a dry run.
Post-incident: stop work, make the area safe, and preserve the scene. Report through the site's incident and near-miss process, including the radio failure, the pendulum and the tag line handler's exposure. Quarantine the failed radio for investigation. Hold a debrief with the operator, riggers and the second crane crew. Review the lift plan and risk assessment before any resumption, and do not resume until the communication and exclusion-zone controls are verified. Record the event in the crane log and the site register.