The people who strung the line - which is used in a sport akin to tightrope walking - had filed an aviation safety notice, raising questions about the air alert system.

Federal aviation records show a notice was issued to pilots that a tightrope would be stretched across a mountainous area of Arizona, providing a warning to watch out for the temporary obstacle.

A fatal Arizona helicopter crash involving a high-altitude slackline has renewed scrutiny of the FAA’s NOTAM system ahead of its planned upgrade.

This article originally published at Helicopter crashes into kilometer-long slackline in Arizona, killing four.

(AP) — Federal aviation records show that a week before a fatal helicopter crash, a notice was issued that a tightrope would be stretched across a mountainous area of Arizona, providing a warning for ...

Slackline warning was issued before helicopter crash that killed groom and nieces on wedding day - The pilot was taking his nieces on a helicopter ride before his wedding ceremony, family said ...

SUPERIOR, Ariz. — The Federal Aviation Administration reportedly issued a warning to pilots of a tightrope near Superior in the days leading up to a deadly helicopter crash. The helicopter crashed in ...

SUPERIOR, Arizona — Three young women reported to be from Oregon and a 59-year-old pilot were killed Friday when their helicopter struck a recreational slackline strung across mountains near Superior, ...