A NOTAM warning of a slackline stretched across a mountainous area of central Arizona was issued days before a fatal helicopter crash that killed the pilot and three passengers, according to federal aviation records, the Associated Press reported.
The helicopter, an MD Helicopters 369FF, struck the line near Telegraph Canyon on Jan. 2 before falling to the bottom of the canyon. Investigators with the National Transportation Safety Board are now examining wreckage and operational factors as part of the ongoing investigation.
According to the Associated Press, the NOTAM was issued Dec. 26 and advised pilots that a slackline more than half a mile long would be installed temporarily, flagged and lighted, in the area roughly 64 miles east of Phoenix. The helicopter departed from Pegasus Airpark (5AZ3), and a witness reported seeing the aircraft strike the line.
“Power lines and unmarked cables are a perpetual concern for helicopter pilots because they are inherently difficult to see,” Tom Anthony, director of the Aviation Safety and Security Program at the University of Southern California, told the AP.
The International Slackline Association expressed condolences for those involved in the helicopter crash in a statement, but noted that the line was marked and that a NOTAM had been issued.
“The International Slackline Association (ISA) is heartbroken to learn of a tragic incident that occurred in the United States on January 2nd 2026 in which a helicopter collided with a 1km long highline,” the organization posted on social media. “The highline had aviation markers attached to it. The FAA had been informed of the highline and a NOTAM (Notice to Air Missions) had been issued before the collision.”
Authorities identified the pilot as 59-year-old David McCarty, along with his nieces Rachel McCarty, Faith McCarty and Katelyn Heideman. McCarty founded Columbia Basin Helicopters in the 1990s, a contractor supporting firefighting and agricultural operations across multiple western states.
Federal investigators have not yet determined whether any other factors may have contributed to the accident.
