Looking for experienced excavator operators/engineers to review a fatal Kubota U27-4 incident from a human factors perspective
I'm looking for opinions from experienced excavator operators, mechanics, engineers or anyone familiar with working around mini excavators.
I'm reviewing the circumstances of a workplace fatality involving a Kubota U27-4 and I'm interested in understanding the engineering and operator factors involved. I'm not looking for opinions on legal liability, only whether the reconstruction makes sense from an operational point of view.
Scenario
Kubota U27-4 mini excavator.
Working in a field.
The left-hand side of the excavator (cab door side) was running parallel to a steel fence approximately 10 metres long, supported by steel RSJ posts.
The excavator was working very close to the fence.
The bucket was reported to have been raised.
The operator was found with their head outside the left-hand cab door, with the remainder of their body still inside the machine.
Cause of death was chest compression after becoming trapped between the excavator and an RSJ.
The machine was later examined and no significant mechanical defects were found.
However, investigators also noted:
The left-hand mirror was broken and the mirror glass was missing prior to this.
There were fresh scrape marks on the left-hand side/door frame which appeared consistent with contact against an RSJ or similar steel structure.
The reconstruction put forward is that the operator leaned or slumped out of the cab, contacted the slew control, and the upper structure rotated into the RSJ, trapping the operator.
Questions
I'm interested in hearing from people who regularly operate excavators.
If you were working parallel to a long steel fence with RSJ posts, would a missing left-hand mirror affect how you operated the machine?
Would it make you more likely to lean out of the cab to judge your clearance?
If there were scrape marks on the side of the excavator, would that suggest the machine had already contacted the fence or RSJ before the fatal entrapment?
Is this sequence something you could realistically see happening?
Is there anything else that stands out from an operator's perspective that investigators should consider?
I'm looking for practical opinions from people with real experience operating these machines rather than speculation.
Thanks in advance.