A tragic aviation incident in Arizona’s remote canyon terrain has claimed four lives after a helicopter collided with an extreme sport slackline. The Pinal County Sheriff’s Office confirmed the January 2nd crash near Telegraph Canyon, east of Phoenix, involving a recreational slackline stretching over one kilometer across mountain ranges.
According to witness accounts provided to emergency services, the aircraft struck a segment of the tensioned fabric line before plummeting to the canyon floor. All occupants perished in the impact, subsequently identified as pilot David McCarty, 59, and his three nieces from Oregon: Rachel McCarty, 23, Faith McCarty, 21, and Katelyn Heideman, 21.
The National Transportation Safety Board (NTSB) and Federal Aviation Administration (FAA) have launched a comprehensive investigation, transporting wreckage to secure facilities for detailed examination. Notably, the extreme sports participants had complied with aviation safety protocols by filing a Notice to Air Missions (Notam) and attaching aviation markers to enhance visibility—raising critical questions about whether the pilot accessed the hazard alert system.
Slacklining, an increasingly popular adventure sport, involves traversing specialized fabric lines with less tension than traditional tightropes, enabling dynamic bouncing maneuvers. Highlining—the practice of stringing lines at significant altitudes—represents the sport’s most extreme variant.
Aviation safety experts have long criticized the Notam system as outdated and cumbersome. Tim Kiefer, air traffic management professor at Embry-Riddle Aeronautical University, explained to Phoenix media that pilots must manually sift through numerous notices—some irrelevant or expired—to identify pertinent hazards. The Department of Transportation had previously announced plans to replace this ‘legacy and aging’ system by February 2026.
The International Slackline Association expressed profound grief over the incident while emphasizing participants’ adherence to safety measures. The NTSB continues examining whether slacklines have previously caused aviation accidents, noting ongoing investigations into wire-strike incidents that pose particular challenges for pilot visibility.