Lessons LearnedCrawler Friction Crane

Project

• Fort Campbell Utility Privatization Capital Improvements Program Wastewater Treatability Improvements, DBO

Nature of the Incident

• A subcontractor operator was in an idling 45 ton American

Crane crawler/friction crane when he turned around to place

paperwork behind his seat. Doing so he inadvertently

disengaged the foot brake which allowed the headache ball to

free fall approximately 40’ to the ground; narrowly missing a

fellow employee.

Root Causes

• Neither the airbrake or the master clutch were engaged; either would have prevented the free fall of the headache ball.

Contributing Factor

• Subcontractor crane operator was certified for hydraulic crane operation and not specifically crawler/friction cranes. The operator’s experience related to friction cranes is unknown as he was immediately terminated by his employer not allowing a post incident interview/statement.

• Locating the headache ball or any load over an area occupied by employees places them in danger of being struck by falling loads or equipment.

Lessons LearnedCrawler Friction Crane

Lessons Learned

• Always verify qualifications and experience (resume) for

crane operators.

– There are differences in qualification between

various types of cranes; mobile, tower, lattice

boom vs. telescoping boom.

– Individuals may have several years of experience

with operating cranes. However, that experience

could be more with one type of crane than

another.

• On crawler friction cranes the air brake shall be engaged

when not physically hoisting/lowering a load.

• Never disengage the master clutch that would allow a

friction crane to be in a free fall mode. On crawler friction

cranes the clutch should be engaged and “power down”

lowering practices followed.

• Never allow an individual to leave the site of an incident

without allowing for an exit interview/statement.

• After any serious incident involving a crane (i.e. struck

against, dropped load, contact with live electrical, etc.) a

third party crane inspection shall be performed to verify

there was no damage to the crane, its components or

any faulty item that may have contributed to the incident.