当局称，一架私人直升机周五在凤凰城外的山脉坠毁，机上四人全部遇难。
据美国联邦航空管理局报道，坠机发生在当地时间周五上午11点左右，涉及一架MD 369FF直升机。
皮纳尔县治安官办公室表示，一名拨打911电话的目击者称，直升机撞上了一条休闲放松绳的一部分，这条绳子在坠入峡谷底部之前就已经穿过了山脉。
松绳是一种类似走钢丝的活动，包括在两个锚定点之间的扁平织带上保持平衡，根据美国走扁带公司.
直升机上四人的身份尚未公开，但警长办公室表示，飞行员是一名来自皇后溪的59岁男子，乘客是三名20岁出头的女性家庭成员。
根据警长办公室的说法，直升机从亚利桑那州皇后溪的飞马机场出发，位于苏必利尔以西。
苏必利尔位于凤凰城以东将近70英里。
根据皮纳尔县治安官办公室的说法，工作人员工作了几个小时，以进入位于亚利桑那州苏必利尔州南部电报峡谷附近的山区的偏远坠机现场。
美国国家运输安全委员会和美国联邦航空局正在调查这起坠机事件。
根据通知，联邦航空局在该地区发布了临时飞行限制，“为搜索和救援行动提供一个安全的环境”。
Helicopter crashes in Arizona mountains, crews working to reach remote site: Authorities
A private helicopter crashed in a mountain range outside Phoenix on Friday, killing all four people aboard, authorities said.
The crash occurred around 11 a.m. local time Friday and involved an MD 369FF helicopter, according to the Federal Aviation Administration.
The Pinal County Sheriff's Office said an eyewitness who called 911 said the helicopter struck part of a recreational slackline that had been strung up across the mountain range before falling to the bottom of the canyon.
Slacklining is an activity, similar to tightrope walking, that involves balancing on a flat piece of webbing between two anchor points,according to Slackline U.S.
The identities of the four people on board the helicopter have not been made public, but the sheriff's office said the pilot was a 59-year-old man from Queen Creek and passengers were three female family members in their early 20s.
The helicopter had departed from Pegasus Airpark in Queen Creek, Arizona, located west of Superior, according to the sheriff's office.
Superior is nearly 70 miles east of Phoenix.
Crews worked for several hours to access the remote crash site, located in the mountains near Telegraph Canyon, south of Superior, Arizona, according to the Pinal County Sheriff's Office.
The National Transportation Safety Board and the FAA are investigating the crash.
A temporary flight restriction was issued by the FAA over the area "to provide a safe environment for search and rescue ops," according to the notice.
