Lessons From a Queensland Zipline Fatality

This article is about a failure that was entirely predictable, entirely preventable, and entirely hidden until it was not. Dean Anson Sanderson's death during a zipline ride in Far North Queensland clearly falls into that category, a termination failure that exposes how superficial assurance and visual checks can lull organisations into thinking life-critical systems are safe.

In December 2019, a zipline cable failed mid-span in the Daintree region, sending two riders plunging approximately 20–25 metres to the ground. Dean Sanderson died from his injuries, while his wife survived with serious injuries and, no doubt lifelong trauma and grief for losing her husband during a time of joy. The subsequent coronial process has confirmed what many safety and engineering professionals already suspected: the wire rope termination method used was fundamentally unsuitable and inadequately installed.

The cable was secured using wire rope grips, commonly referred to as bulldog clips.

Expert evidence before the coronial pre-inquest in December 2025 confirmed the grips were significantly under-torqued, reportedly as little as one-seventh of the torque required under applicable engineering standards. Under load, the rope progressively slipped until it fully unspooled.

The inquest proper is scheduled for 02-06 Mar 26 before the Coroners Court of Queensland and is expected to examine not only the mechanical failure but also the adequacy of industry practice, operator competence, and regulatory guidance in the adventure tourism sector.

Why this matters beyond adventure tourism

Termination points are where systems quietly fail. They are often treated as install-and-forget components, assumed to be safe because they are static, familiar, and visually intact. In reality, they are dynamic interfaces subjected to load cycles, vibration, creep, corrosion, and human error.

This failure mechanism is not unique to ziplines. This issue also applies to lifting equipment, load securing, fall protection systems, crane cables, towing connections, and any system that depends on friction, torque, or following procedures instead of secure mechanical locking.

At the time of this incident, I was serving as a Staff Officer Risk Management, within the Australian Air Force Cadets National Headquarters, with responsibility for reviewing the risk management processes and systems of work used by proposed contracted adventure activity providers delivering cadet activities around the country. When the details of this fatality emerged, it was immediately clear that the lessons extended well beyond a single operator or jurisdiction.

Unfortunately, this particular incident ended selfish arguments that were being fought, with me as the punching bag for exercising a level of rigour for the protection of other people's children (cadets). Behaviours and attitudes...

I reported the incident to my superiors and then downstream to the safety managers in Queensland and throughout the safety network, highlighting the need to ensure appropriate levels of rigour were being applied before intending to engage adventure activity companies offering zip line activities. The intent was simple: to prevent the same latent failure from occurring unnoticed in any activity involving cadets.

The uncomfortable truth about assurance

One of the most concerning aspects of this case is that the system likely passed routine inspections. Wire rope grips can look fine while being catastrophically unfit for purpose. Torque loss is not visually obvious, and unless installers are trained, supervised, and independently verified, incorrect installation becomes normalised.

This is the same trap seen repeatedly across high-risk industries. Assurance becomes about paperwork and presence rather than physics and failure modes. If a control relies on a human remembering to tighten something correctly and then remembering to re-check it forever, it is not a robust control.

Regulatory implications

Following the incident, Workplace Health and Safety Queensland undertook enforcement action, although prosecutions did not result in convictions and the operating company has since deregistered. The upcoming inquest provides an opportunity for clearer recommendations around design standards, competency requirements, and the prohibition of inappropriate termination methods in adventure systems.

The regulator involved, Workplace Health and Safety Queensland, has previously issued guidance on zipline safety, but guidance alone does not correct deeply embedded industry habits. Clear standards, enforceable expectations, and competent verification are required.

What leaders should take from this

If you are responsible for any system where failure equals fatality, ask yourself three questions.

First, are termination points and interfaces explicitly identified as critical components, or are they buried inside generic inspection checklists?

Second, is installation and ongoing verification based on measurable criteria such as torque values, proof loading, or independent inspection, or is it assumed safe because it looks fine?

Third, would you be comfortable explaining the control to a coroner, not a consultant, after someone has died?

If the answer to any of those questions is no, you do not have assurance. You have hope, and hope is not a control.

This case is not about hindsight. The failure mode was well known long before 2019.

The lesson now is whether organisations and regulators are prepared to act before the next termination lets go, rather than after.

Feel free to ask me what it feels like to go from enjoying a holiday to having your life threatened in an instant. It changes you forever.

Red pill or blue pill...

SJ