GRANBY, Colo. — Investigators released their final report after spending months digging into the death of a passenger on a Ski Granby Ranch ski lift. The report pointed the finger of blame at a newly installed electronic drive behind the lift.
A team of investigators dug into the Dec. 29, 2016 death of Kelly Huber, 40, for the Colorado Passenger Tramway Safety Board.
Huber, a Texas mother, and her two young daughters were on a holiday trip to Colorado. They were riding the Quick Draw Express lift when their chair began to wildly swing from side to side and struck a lift tower -- hurling all three 25 feet onto hard-packed snow.
The fall claimed Huber's life and injured her daughters. Now investigators have released the cause, blaming the rare death on the electric drive — installed in the summer of 2016 — which pulled the lift.
Ski deaths are rare, with the last death reported in 2002
"The incident that occurred on December 29, 2016 at Granby Ranch was unprecedented," investigators wrote in their report, suggesting they hadn't seen anything like it before.
They said a new electric motor drive, which wasn't properly tuned to settings appropriate for operating a ski lift, was the main culprit. They said the new drive's improper tuning resulted in a rapid change in speed, influencing the chairlift to swing wildly.
Many witnesses reported the lift was repeatedly speeding up and slowing down just before the fatal fall. And investigators found evidence of "rapid and significant accelerations/decelerations of the lift occurred immediately prior to the incident," according to the report.
The lift operator said he didn’t remember changing speeds. But the report said, “Fast/Slow speed commands by the operator in rapid succession” along with the tuning of the new electrical drive and other factors “resulted in excessive (Chair 58) swing leading to the collision at Tower 5.”
A witness riding on the lift wrote in a statement that they "experienced repeated stops and starts, bouncing, swing back and forward." Another skier wrote their swaying chair "just missed striking Tower 4."
A ski patroller wrote he was on a chair in front of the Hubers when he heard a rumble on the lift cable and he experienced the "largest vertical motion I had ever felt in a lift line." He grabbed the back of his chair and told three children riding with him to hang on.
The patroller said he heard a "thunk" and looked back to see Huber and her daughters falling from the chair.
“The mother was visibly holding one of the children in what appeared to be an attempt to protect the child from the impact of landing,” he wrote.
Another chairlift rider wrote that he saw the trio land on the snow and heard one of the injured people screaming, "Don’t let her die."
Investigators said when a cable surges, causing wild swinging, it takes place toward the bottom of the lift where the tension is lowest.
The swinging may have impacted the Hubers' four-person chair more because, with only the mom and small girls onboard, it was lighter in comparison to more heavily loaded chairs on the lift.
Other factors
The investigators said other possible factors in the death could have been the complexity of the electrical drive's controls. State engineers said they could not confirm if the new electrical drive was properly interfaced with the lift's original, 1999 control system because of the older, proprietary programming.
They said it's also possible for the cable's tension to not be constant, along with other electrical problems.
Also last year, one of the control boards in the original electrical drive was replaced. This appeared to cause some instability in the electric motor’s current but the problem appeared to be smoothed out with fine-tuning, the report said.
Those other findings will need to be investigated, officials said.
Recommendations
The board released a host of recommendations, including submitting all drive-tuning settings to the Colorado Passenger Tramway Safety Board before implementing them in use. Other recommendations:
- New testing for lift speed under different load weights.
- Speed change delays to allow lift cables to come to acceptable speeds for stabilization purposes.
- A mandatory stop time to allow a cable to come to a full, stable stop before allowing it to resume movement.
- Adding a "black box" device for all aerial lifts to collect data about stops, starts, speed changes and more.
- Additional recommendations for digital and analog drive best practices.
Disciplinary action
State investigators are still reviewing whether disciplinary action will be taken.
It's not yet known if Huber's family has or will file a lawsuit in the chairlift death.
Below, you can view an interactive timeline of the events leading up to the deadly accident at Ski Granby Ranch as well as the response from city, ski and law enforcement officials, including their findings.
Late Thursday evening, Ski Granby Ranch sent the following statement concerning the CPTSB report.
"Granby Ranch is reviewing the report released yesterday by the Colorado Passenger Safety Tramway Board on the incident at Granby Ranch on December 29, 2016. This is a 151 page report that deserves careful review. Granby Ranch continues to comply with all Tramway Board directives. We would again like to offer our condolences to the Huber family for their loss. Granby Ranch is committed to the health and safety of its guests."
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